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The Low Carb Myth

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The “Goldilocks Effect”

Author: Dr. Stephen Chaney

low carb dietThe low carb wars rage on. Low carb enthusiasts claim that low-carb diets are healthy. And they claim the lower you go, the healthier you will be. Let me start with some definitions:

  • The typical American diet is high carb. It gets about 55% of its calories from carbohydrates. [Note: The Mediterranean and DASH diets also get about 55% of their calories from carbohydrates. I’ll talk more about that later.]
  • Moderate carb diets get 26-46% of their calories from carbohydrates. Examples include the low carb Mediterranean diet and the Paleo, South Beach, and Zone diets.
  • Low carb diets get <26% of their calories from carbohydrates. The Atkins diet is the classic example of a low carb diet.
  • Very low carb diets get <10% of their calories from carbohydrates. Examples are the Keto and Carnivore diets.

And I don’t need to tell you that the Keto and Carnivore diets are receiving a lot of favorable press lately.

But some health experts warn that low carb and very low carb diets may be dangerous. Several studies have reported that low carb diets increase the risk of mortality (shorten lifespan).

As a consumer you are probably confused by the conflicting claims. Are low carb diets healthy, or is this another myth? In this issue of “Health Tips From the Professor” I am going to discuss two very large studies that came to opposite conclusions.

Both were what we call meta-analysis studies. Simply put, that means they combine the data from several smaller studies to obtain more statistically reliable data. But as Mark Twain said, “There are lies. There are damn lies. And then there are statistics.”

The first study, called the Prospective Urban Rural Epidemiology (PURE) study, was published a few years ago. It included data from 135,335 participants from 18 countries across 5 continents. That’s a very large study, and normally we expect very large studies to be accurate.

It showed a linear relationship between carbohydrate intake and mortality. Simply put, the more carbohydrate people consumed, the greater their risk of premature death. The results from the PURE study had low carb enthusiasts doing a victory lap and claiming it was time to rewrite nutritional guidelines to favor low carb diets.

Whenever controversies like this arise, reputable scientists are motivated to take another look at the question. They understand that all studies have their weaknesses and biases. So, they look at previous studies very carefully and try to design a study that eliminates the weaknesses and biases of those studies. Their goal is to design a stronger study that reconciles the differences between the previous studies.

And this study had two glaring weaknesses.

  • The percent carbohydrate intake ranged from 40% to 80%. It showed that a moderate carbohydrate intake might be healthier than a high carbohydrate intake, but it provided no information about low carb or very low carb diets.
  • The data was primarily from Asian countries. It was not clear whether it was relevant to the kind of diets consumed in North America and Europe.

A second study published a year later (SB Seidelmann et al, The Lancet, doi.org/10.1016/S2468-2667(18)30135-X  eliminated these weaknesses and resolved the conflicting data.

How Was The Second Study Done?

low carb diet studyThis study was performed in two parts. This first part drew on data from the Atherosclerosis Risk in Communities (ARIC) study. That study enrolled 15,428 men and women, aged 45-64, from four US communities between 1987 and 1989. This group was followed for an average of 25 years, during which time 6283 people died.

Carbohydrate intake was calculated based on food frequency questionnaires administered when participants enrolled in the study and again 6 years later. The study evaluated the association between carbohydrate intake and mortality.

The second part was a meta-analysis that combined the data from the ARIC study with all major clinical studies since 2007 that measured carbohydrate intake and mortality and lasted 5 years or more. The total number of participants included in this meta-analysis was 432,179, and it included data from previous studies that claimed low carbohydrate intake was associated with decreased mortality.

The Low Carb Myth

GravestoneThe results from the ARIC study were:

  • The relationship between mortality and carbohydrate intake was a U-shaped curve.
    • The lowest risk of death was observed with a moderate carbohydrate intake (50-55%). This is the intake recommended by current nutrition guidelines.
    • The highest risk of death was observed with a low carbohydrate intake (<20%).
    • The risk of death also increased with very high carbohydrate intake (>70%).
  • When the investigators used the mortality data to estimate life expectancy, they predicted a 50-year-old participant would have a projected life expectancy of:
    • 33.1 years if they had a moderate intake of carbohydrates.
    • 4 years less if they had a very low carbohydrate intake.
    • 1 year less if they had a very high carbohydrate intake.
  • The risk associated with low carbohydrate intake was affected by what the carbohydrate was replaced with.
    • When carbohydrates were replaced with animal protein and animal fat there was an increased risk of mortality on a low-carb diet.

The animal-based low-carb diet contained more beef, pork, lamb, chicken, and fish. It was also higher in saturated fat.Beans and Nuts

    • When carbohydrates were replaced with plant protein and plant fats, there was a decreased risk of mortality on a low-carb diet. The plant-based low-carb diet contained more nuts, peanut butter, dark or whole grain breads, chocolate, and white bread. It was also higher in polyunsaturated fats.
  • The effect of carbohydrate intake on mortality was virtually the same for all-cause mortality, cardiovascular mortality, and non-cardiovascular mortality.
  • There was no significant effect of carbohydrate intake on long-term weight gain (another myth busted).

The results from the dueling meta-analyses were actually very similar in some respects. When the data from all studies were combined:

  • Very high carbohydrate diets were associated with increased mortality.
  • Meat-based low-carb diets increased mortality, and plant-based low-carb diets decreased mortality.
  • The results were the same for total mortality, cardiovascular mortality, and non-cardiovascular mortality.

The authors concluded: “Our findings suggest a negative long-term association between life-expectancy and both low carbohydrate and high carbohydrate diets…These data also provide further evidence that animal-based low carbohydrate diets should be discouraged.

Alternatively, when restricting carbohydrate intake, replacement of carbohydrates with predominantly plant-based fats and proteins could be considered as a long-term approach to healthy aging.”

Simply put, that means if a low carb diet works best for you, it is healthier to replace the carbs with plant-based fats and protein rather than animal-based fats and protein.

The “Goldilocks Effect”

Goldilocks EffectThis study also resolved the discrepancies between previous studies. The authors pointed out that the PURE study relied heavily on data from Asian and developing countries, and the average carbohydrate intake is very different in Europe and the US than in Asian and developing countries.

  • In the US and Europe mean carbohydrate intake is about 50% of calories and it ranges from 25% to 70% of calories. With that range of carbohydrate intake, it is possible to observe the increase in mortality associated with both very low and very high carbohydrate intakes.
  • The US and European countries are affluent, which means that low carb enthusiasts can also afford diets high in animal protein.
  • In contrast, white rice is a staple in Asian countries, and protein is a garnish rather than a main course. Consequently, overall carbohydrate intake is greater in Asian countries and very few Asians eat a truly low carbohydrate diet.
  • High protein foods tend to be more expensive than high carbohydrate foods. Thus, very few people in developing countries can afford to follow a very low carbohydrate diet, and overall carbohydrate intake also tends to be higher in those countries.

Therefore, in Asian and developing countries the average carbohydrate intake is greater (~61%) than in the US and Europe (~50%), and the range of carbohydrate intake is from 45% to 80% of calories instead of 25% to 70%. With this range of intake, it is only possible to see the increase in mortality associated with very high carbohydrate intake.

In fact, when the authors of the current study overlaid the data from the PURE study with their ARIC data, there ARIC Studywas an almost perfect fit. The only difference was that their ARIC data covered both low and high carbohydrate intake while the PURE study touted by low carb enthusiasts only covered moderate to high carbohydrate intake.

[I have given you my rendition of the graph on the right. If you would like to see the data yourself, look at the paper.]

Basically, low carb advocates are telling you that diets with carbohydrate intakes of 26% or less are healthy based on studies that did not include carbohydrate intakes below 40%. That is misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets.

In short, the ARIC study finally answered the question, “How much carbohydrate should we be eating if we desire a long and healthy life?” The answer is “Enough”.

I call this “The Goldilocks Effect”. You may remember “Goldilocks And The Three Bears”. One bed was too hard. One bed was too soft. But one bed was “just right”. One bowl of porridge was too hot. One was two cold. But one was “just right”.

According to this study, the same is true for carbohydrate intake. High carbohydrate intake is unhealthy. Low carbohydrate intake is unhealthy. But moderate carbohydrate intake is “just right”.

What Does This Study Mean For You?

confusionThere are several important take-home lessons from this study:

1) All major studies agree that very high carbohydrate intake is unhealthy. In part, that reflects the fact that diets with high carbohydrate intake are likely to be high in sodas and sugary junk foods. It may also reflect the fact that diets which are high in carbohydrates are often low in plant protein or healthy fats or both.

2) All studies that cover the full range of carbohydrate intake agree that low and very low carbohydrate diets are also unhealthy. They shorten the life expectancy of a 50-year-old by about 4 years.

3) The studies quoted by low carb enthusiasts to support their claim that low-carb diets are healthy don’t include carbohydrate intakes below 40%. That means their claims are misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets. Their claims are a myth.

4) Not all high carb diets are created equally. As I noted above, the Mediterranean and DASH diets are just as high in carbohydrates as the typical American diet, but their carbohydrates come from whole fruits and vegetables, whole grains, beans, nuts, and seeds. And multiple studies show that both diets are much healthier than the typical American diet.

5) Not all low carb diets are created equally. Meat-based low-carb diets decrease life expectancy compared to the typical American diets while plant-based low carb diets increase life expectancy.

6) The health risks of meat-based low-carb diets may be due to the saturated fat content or the heavy reliance on red meat. However, the risks are just as likely to be due to the foods these diets leave out – typically fruits, whole grains, legumes, and some vegetables.

7) Proponents of low-carb diets assume that you can make up for the missing nutrients by just taking multivitamins. However, each food group also provides a unique combination of phytonutrients and fibers. The fibers, in turn, influence your microbiome. Simply put, whenever you leave out whole food groups, you put your health at risk.

The Bottom Line

The low-carb wars are raging. Several studies have reported that low carb diets increase risk of mortality (shorten lifespan). However, a study published a few years ago came to the opposite conclusion. That study had low carb enthusiasts doing a victory lap and claiming it is time to rewrite nutritional guidelines to favor low-carb diets.

However, a study published a year later resolves the conflicting data and finally answers the question: “How much carbohydrate should we be eating if we desire a long and healthy life?” The answer is “Enough”.

I call this “The Goldilocks Effect”. According to this study, high carbohydrate intake is unhealthy. Low carbohydrate intake is unhealthy. But moderate carbohydrate intake is “just right”.

Specifically, this study reported:

  1. Moderate carbohydrate intake (50-55%) is healthiest. This is the carbohydrate intake found in healthy diets like the Mediterranean and DASH diets, and is the intake recommended by current nutritional guidelines.

2) All major studies agree that very high carbohydrate intake (60-70%) is unhealthy. It shortens the life expectancy of a 50-year-old by about a year.

3) All studies that cover the full range of carbohydrate intake agree that low carbohydrate intake (<26%) is also unhealthy. It shortens the life expectancy of a 50-year-old by about 4 years.

4) The studies quoted by low carb enthusiasts to support their claim that low-carb diets are healthy don’t include carbohydrate intakes below 40%. That means their claims are misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets.

5) Meat-based low-carb diets decrease life expectancy compared to the typical American diet while plant-based low carb diets increase life expectancy. This is consistent with the results of previous studies.

The authors concluded: “Our findings suggest a negative long-term association between life-expectancy and both low carbohydrate and high carbohydrate diets…These data also provide further evidence that animal-based low carbohydrate diets should be discouraged.”

Simply put, the latest study means that the supposed benefits of low carb diets are a myth.

For more details, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 ______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry textbooks for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

 

 

The Good Cholesterol Myth

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Is Everything You Knew About HDL Wrong?

Author: Dr. Stephen Chaney 

HDL CHolesterolOver the past couple of weeks” I have talked about one of the greatest strengths of the scientific method – namely that investigators constantly challenge, and occasionally disprove, existing paradigms. That allows us to discard old models of how things work and replace them with better ones.

Two weeks ago, I shared a study that disproved the myth that low to moderate alcohol consumption is healthier than total abstinence.

Last week I shared a study that disproved the myth about chocolate helping you lose weight weight.

This week I tackle the “good” cholesterol myth. I will share several studies that challenge the belief that HDL cholesterol is good for your heart.

The belief that HDL is good for your heart has all the hallmarks of a classic paradigm.

  • It is supported by multiple clinical studies.
  • Elaborate metabolic explanations have been proposed to support the paradigm.
  • It is the official position of most medical societies, scientific organizations, and health information sites on the web.
  • It is the recommendation of most health professionals.
  • It has been repeated so often by so many trusted sources that everyone assumes it must be true.

Once we accept the HDL/heart health paradigm as true, we can construct other hypotheses on that foundation. For example:

  • Raising your HDL levels naturally takes effort. Pharmaceutical companies have been pursuing the “magic pill” that raises HDL levels without any effort on your part.
  • Low carb diets like the Keto and Paleo diets are high in saturated fat. The low carb enthusiasts claim this is a good thing because saturated fat raises HDL levels, and HDL is good for your heart.

But what if the paradigm that HDL is good for your heart isn’t true? What if it is a myth? These hypotheses would be like the parable of a house built on a foundation of sand. They will be washed away as soon as the paradigm is critically tested.

Do Drugs That Increase HDL Levels Work?

The first hint that the HDL/heart health paradigm might be faulty happened when a pharmaceutical company developed a drug that selectively increased HDL levels.

The drug company thought they had found the goose that laid golden eggs. Just imagine. People wouldn’t have to lose weight, exercise, or change their diet. They could simply take a pill and dramatically decrease their heart disease risk. A drug like that would be worth billions of dollars.

The problem was that when they tested their drug (torcetrapib) in clinical trials, it had absolutely no effect on heart disease outcomes (AR Tall et al, Atherosclerosis, Thrombosis, and Vascular Biology 27:257-260, 2007).

The pharmaceutical company couldn’t believe it. Raising HDL levels just had to reduce heart disease risk. They concluded they didn’t have the right drug, and they continued to work on developing new drugs.

That was 18 years ago, and no HDL-increasing drug has made it to market. Have they just not found the right drug, or does this mean the HDL/heart health paradigm is incorrect?

Does Saturated Fat Decrease Heart Disease Risk?

Now let’s turn to two claims of low carb enthusiasts.

#1: Saturated fats decrease your risk of heart disease in the context of a low carb diet. I have debunked that claim in several previous issues of “Health Tips From The Professor”. But let me refer you to two articles here – one on saturated fat and heart disease risk and one on low-carb diets.

#2: Saturated fats decrease heart disease risk because they raise HDL levels. This is the one I will address today.

The idea that saturated fats decrease heart disease risk because they raise HDL levels is based on a simplistic concept of HDL particles. The reality is more complex. Several clinical studies have shown:

  • The type of fat determines the property of the HDL particles.
    • When polyunsaturated fats predominate, the HDL particles have an anti-inflammatory effect. When saturated fats predominate, the HDL particles have a pro-inflammatory effect.
  • Anti-inflammatory HDL particles relax the endothelial cells lining our blood vessels. That makes the lining of our blood vessels more pliable, which improves blood flow and reduces blood pressure.
    • Anti-inflammatory HDL particles also help reduce inflammation of the endothelial lining. This is important because an inflamed endothelial lining is more likely to accumulate fatty plaques and to trigger blood clot formation that can lead to heart attacks and strokes.

So, the question becomes, “What good is it to raise HDL levels if you are producing an unhealthy, pro-inflammatory HDL particle that may increase the risk of high blood pressure, heart attacks, and strokes?”

In short, these studies suggest it isn’t enough to just focus on HDL levels. You need to ask what kind of HDL particles you are creating.

So, let’s look at experiments that have challenged the HDL/heart health paradigm.

Is HDL Good For Your Heart?

strong heartOnce the studies were published showing that…

  • Drug-induced increase of HDL levels without any change in health habits is not sufficient to decrease heart attack risk, and…
  • Not all HDL particles are healthy. There are anti-inflammatory or pro-inflammatory HDL particles, which are likely to have opposite effects on heart attack risk…

…some people started to question the HDL/heart health paradigm. And one group came up with the perfect study to test the paradigm.

But before I describe the study, I need to review the term “confounding variables”. Here is a brief synopsis:

  • The studies supporting the HDL/heart health paradigm are association studies. Association studies measure the association between a single variable (in this case, increase in HDL levels) and an outcome (in this case, heart disease events, heart disease deaths, and total deaths).
  • Associations need to be corrected for other variables known to affect the same outcome (things like age, gender, smoking, and diabetes would be examples in this case).
  • Confounding variables are variables that also affect the outcome but are unknown or ignored. Thus, they are not used to correct the associations, which can bias the results.

The Good Cholesterol Myth

The authors of this study (M Briel et al, BMJ 2009:338.b92) observed that most interventions that increase HDL levels also lower LDL levels. Lowering LDL is known to decrease the risk of heart disease deaths. But this effect had been ignored in most studies looking at the association between HDL and heart disease deaths.

They hypothesized that the change in LDL levels was a confounding variable that had been ignored in previous studies and may have biased the results.

To test this hypothesis the authors searched the literature and identified 108 studies with 299,310 participants that:

  • Compared the effect of drugs, omega-3 fatty acids, or diet with either a placebo or usual care.
  • Measured both HDL and LDL levels.
  • Measured reduction in cardiovascular risk.
  • Had a randomized control design.
  • Lasted at least 6 months.

They found that every 10 mg/dl decrease in LDL levels in these studies was responsible for a:Heart Disease Study

  • 1% reduction in heart disease events (both heart disease deaths and non-fatal heart attacks).
  • 2% reduction in heart disease deaths.
  • 4% reduction in total deaths.

After correcting for the effect of decreased LDL levels on these heart disease outcomes, the increase in HDL levels had no statistically significant effect on any of the outcomes.

The authors concluded, “Available data suggest that simply increasing the amount of circulating HDL cholesterol does not reduce the risk of coronary heart disease events, coronary heart disease deaths, or total deaths. The results support reduction in LDL cholesterol as the primary goal for lipid modifying interventions.”

In other words, this study:

  • Supports the author’s hypothesis that LDL levels were a confounding variable that biased the studies supporting the HDL/heart health paradigm.
  • Concludes that increasing HDL levels has no effect on heart disease outcomes, thus invalidating the HDL/heart health paradigm.

In short, this study destroyed the “good” cholesterol myth.

Is Everything You Knew About HDL Wrong?

Peek Behind The CurtainDoes that mean that everything you knew about HDL is wrong? Not exactly. It just means that you may need to change your perspective.

Don’t focus on HDL levels. Peek behind the curtain and focus on what’s behind the HDL levels. For example:

  • Losing weight when overweight increases HDL levels. But the decrease in heart disease outcomes is more likely due to weight loss than to the increase in HDL levels.
  • Exercise increases HDL levels. But the decrease in heart disease outcomes is more likely due to exercise than to the increase in HDL levels.
  • Reversing pre-diabetes or type 2 diabetes increases HDL levels. But the decrease in heart disease outcomes is more likely due to the reversal of diabetes than to the increase in HDL levels.
  • High-dose omega-3 fatty acids increase HDL levels. But the decrease in heart disease outcomes is more likely due to the omega-3 fatty acids than to the increase in HDL levels.
  • The Mediterranean diet increases HDL levels. But the decrease in heart disease outcomes is more likely due to the diet than to the increase in HDL levels.

And if you want to go the drug route:

  • Statins and some other heart drugs increase HDL levels, but the reduction in heart disease outcomes is probably due to their effect on LDL levels rather than their effect on HDL levels.

On the other hand:

  • Saturated fats increase HDL levels. But saturated fats increase heart disease risk and create pro-inflammatory HDL particles. So, in this case the increase in HDL levels is not a good omen for your heart.
  • Drugs have been discovered that selectively increase HDL levels. However, there is nothing of value behind this increase in HDL levels, so the drugs have no effect on heart disease outcomes.

The Bottom Line 

In this article I discuss several studies that have challenged the good cholesterol myth – the belief that HDL is good for your heart.

For example, one group of investigators analyzed the studies underlying the HDL/heart health paradigm. They hypothesized that these studies were inaccurate because they failed to account for the effects of LDL levels on heart disease outcomes.

After correcting for the effect of decreased LDL levels on heart disease outcomes in the previous studies, the authors showed that increases in HDL levels had no significant effect on any heart disease outcome.

The authors concluded, “Available data suggest that simply increasing the amount of circulating HDL cholesterol does not reduce the risk of coronary heart disease events, coronary heart disease deaths, or total deaths. The results support reduction in LDL cholesterol as the primary goal for lipid modifying interventions.”

In other words, this study:

  • Supports the author’s hypothesis that LDL levels were a confounding variable that biased the studies supporting the HDL/heart health paradigm.
  • Concludes that increasing HDL levels has no effect on heart disease outcomes, thus invalidating the HDL/heart health paradigm.

Does that mean that everything you knew about HDL is wrong? Not exactly. It just means that you need to change your perspective. Don’t focus on HDL levels. Focus on what’s behind the HDL levels. For more information on that, read the article above.

For more information on this study, and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

_________________________________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

________________________________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

The Alcohol Myth

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How Were We Led Astray?

Author: Dr. Stephen Chaney 

You have probably heard that moderate alcohol consumption is healthier than complete abstinence from alcohol. It is certainly a popular viewpoint.

It is also a scientific paradigm. By that I mean:

  • It is supported by multiple clinical studies.
  • Elaborate metabolic explanations have been proposed to support this paradigm.
  • It is the official position of most medical societies, scientific organizations, and health information sites on the web.
  • It is the recommendation of most health professionals.
  • It has been repeated so often from so many trusted sources that everyone assumes it must be true.

But is it a myth? You may have been surprised when you saw recent headlines saying, “Having an alcoholic drink or two per day is not healthier than abstaining.”

Today I will review the study (J Zhao et al, JAMA Network Open, 6(3): e236185, 2023) behind the headlines and tell you what it means for you.

But first, I want to explain to you how the scientific method works. That’s because this study is a perfect example of the scientific method in action.

How Were We Lead Astray?

I have described the scientific method in detail in my books “Slaying The Food Myths” and “Slaying The Supplement Myths”, which you will find here.

Today, I will just give you a brief synopsis of the scientific method.

1) Most scientific studies are designed to disprove existing scientific paradigms. This is such a study.

  • In the scientific world, there is no glory in being the 10th person to prove that a scientific paradigm is correct. The glory comes from being the first person to disprove a scientific paradigm and create a new paradigm in the process.
  • This constant testing of existing paradigms is one of the most important strengths of the scientific method.

2) There is no perfect study. Every study has its flaws.

  • “Confounding variables” are flaws that can be the Achilles Heel of any association study.

Now let me explain the significance of these statements in the context of the current study:

  • All the studies supporting the current paradigm were association studies. Association studies measure the association between a selected variable and an outcome. For these studies, the selected variable was alcohol consumption, and the outcome was increased mortality.
  • Association studies try to statistically correct for other variables known to affect the outcome. For example, diseases like heart disease, diabetes, and cancer increase the risk of premature death. These are known variables that would be corrected for in any well-designed study of alcohol consumption and mortality.
  • “Confounding variables” are unknown variables that also affect the outcome of the study. But since they are unknown, they are not corrected for.

Let me give you a simplistic example of a confounding variable. Let’s say you were doing a study of dietary habits, and you found an association between ice cream consumption and mortality. You might conclude that ice cream consumption is bad for you. It increases your risk of dying.

But then you might remember that ice cream consumption increases during the summer. And then you might reason that people swim more during the summer, and there is a correlation between swimming and drowning deaths.

Swimming could be a confounding variable. To make sure that your initial conclusion that ice cream increases the risk of dying was correct, you would need to correct your data for swimming deaths during the summer and see if you still found a correlation between ice cream consumption and mortality.

Could The Current Paradigm Be Incorrect?

SkepticYou might be thinking, “What does this have to do with studies on the correlation between alcohol consumption and increased mortality?” Let me explain.

The baseline group for these comparisons was the abstainers – the group consuming no alcohol. Previous studies have compared the mortality risk associated with various amounts of alcohol consumption with the mortality risk of the abstainer group. This sounds like a reasonable approach.

But the investigators challenging the current paradigm noted that the “abstainer group” in previous studies included both lifetime abstainers and former drinkers who had become abstainers. They hypothesized that the “former drinkers” group may have become abstainers because of health issues related to excess alcohol consumption.

In short, they hypothesized that the “former drinkers” group was a confounding variable that biased the results of the previous studies. They hypothesized that the “lifetime abstainers” group was a more appropriate baseline group for this kind of study. They then set out to prove their hypothesis.

How Was This Study Done?

clinical studyThe investigators searched the literature and found 107 studies with 4.8 million participants published between 1980 and July 21, 2021, that:

  • Assessed the correlation between alcohol consumption and mortality.
  • Had data that allowed the investigators to separate lifetime abstainers from former drinkers who had become abstainers.

The investigators divided alcohol consumption into low, moderate, high, and very high categories based on the ounces of alcohol consumed per day. Since ounces of alcohol is not an easy measure for most of us, I have converted ounces/day to drinks/day based on the CDC definition of a drink (a 12-ounce beer, 5-ounce glass of wine, or 1.5 ounces of a distilled spirit like gin or vodka). And to make it even simpler, I have rounded to the nearest whole number. With that said, here are the classifications.

  • Low alcohol intake = 1-2 drinks/day.
  • Moderate alcohol intake = 2-3 drinks/day.
  • High alcohol intake = 3-4 drinks/day.
  • Very high alcohol intake = >4 drinks/day.

The risk of death associated with each of these intake levels was compared the risk of death of their preferred baseline group, the “lifetime abstainers”.

Finally, the data were corrected for other variables known to influence the correlation between alcohol consumption and mortality, namely age, sex, heart health, social status, race, diet, exercise, BMI, and smoking status. [These are known variables and had been adjusted for in most previous studies.]

The Alcohol Myth

Red WineWhen the investigators compared the mortality risk of former drinkers who had become abstainers with lifetime abstainers:

  • The former drinkers were 31% more likely to die, and this difference was highly significant.
  • This is consistent with their hypothesis that the “former drinkers” group was a confounding variable that may have biased the conclusions of previous studies.

When they compared the mortality risk of various levels of alcohol consumption with lifetime abstainers instead of all abstainers, they found:

  • The risk of mortality associated with low (1-2 drinks/day) and moderate (2-3 drinks/day) alcohol intake was statistically identical to the risk of mortality for lifetime abstainers.
  • The high alcohol intake group (3-4 drinks/day) was 24% more likely to die than the lifetime abstainers.
  • The very high alcohol intake group (>4 drinks/day) was 39% more likely to die than the lifetime abstainers.

In short, when lifetime abstainers were used as the baseline group, low to moderate alcohol intake did not reduce the risk of dying, as previous studies had suggested. This study suggests the idea that low to moderate alcohol consumption is good for us may not be accurate. It may be a myth.

Finally, there was a significant gender difference in the effect of alcohol consumption on mortality.

For women:

  • Even moderate alcohol consumption was associated with an increased risk of mortality. Only low alcohol consumption posed no increase in mortality.
  • The increased risk of mortality for women was significantly higher than for men with every level of alcohol consumption.

The authors concluded, “In this…meta-analysis, daily low or moderate alcohol intake was not significantly associated with all-cause mortality risk, while increased risk was evident at higher consumption levels, starting at lower levels for women than for men.”

Of course, this isn’t the end of the story. The scientific method will continue. Old paradigms don’t die easily. Other investigators will challenge the conclusions of this study. Stay tuned. I will give you updates as future studies are published.

What Does This Study Mean For You?

confusionIf you like to imbibe, there are two important takeaways from this study.

The bad news is that you can no longer claim that a drink or two a day is healthier than total abstinence from alcohol.

The good news is that this and every study preceding it have found that a drink or two a day is no less healthy than total abstinence. The studies found no increase in mortality associated with low to moderate alcohol intake.

[However, low to moderate alcohol intake may increase your risk of specific diseases. For example, many studies suggest that even low alcohol intake is associated with an increased risk of breast cancer.]

This study also agrees with previous studies that high alcohol intake increases your risk of death, and women are more susceptible to adverse effects of alcohol intake than men.

So, while this study challenges the existing paradigm that low to moderate alcohol intake is beneficial, it does not change the current recommendations on alcohol intake by most health organizations.

For example, the current CDC guidelines are:

  • Adults of legal drinking age should limit alcohol intake to 2 drinks or less per day for men and one drink or less per day for women.
  • Adults who do not drink alcohol should not start. [The current study strengthens this recommendation because it takes away the excuse that low to moderate alcohol consumption is healthier than abstinence.]
  • Drinking less is better than drinking more.

The CDC guidelines also note that the risk of some cancers increases even at very low levels of alcohol consumption.

Finally, the CDC recommends that some people never consume alcohol, including:

  • Women who are pregnant or might become pregnant.
  • Anyone younger than 21.
  • Anyone with medical conditions or medications that interact with alcohol.
  • Anyone recovering from an alcohol use disorder or who has trouble controlling the amount they drink.

The Bottom Line 

A recent study is a perfect example of the scientific method in action. Scientists are constantly challenging the existing scientific paradigms, and this is an important strength of the scientific method.

A group of scientists recently published a study challenging the paradigm that low to moderate alcohol intake is healthier than total abstinence from alcohol.

They hypothesized that previous studies supporting this paradigm had a common methodological flaw, corrected for the flaw, and reanalyzed the data from 104 studies with a total of 4.8 million participants.

The revised data showed no health benefit of low to moderate alcohol consumption compared to total abstinence. When you look at the data more closely, the current paradigm may be a myth.

  • This is a major change to the existing paradigm because it removes the justification for low to moderate alcohol consumption.

However, the revised data did not differ from previous studies in the following ways:

  • There is no health risk associated with low to moderate alcohol intake compared to total abstinence.
  • High alcohol intake (>3 drinks/day) is associated with increased mortality.
  • Women are more sensitive to the adverse effects of alcohol than men.

So, this study does not change current guidelines for alcohol consumption.

For more information on this study, what it means for you, and the CDC guidelines on alcohol consumption read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

_________________________________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________________________

About The Author

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading Biochemistry textbooks for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Do Omega-3s Benefit Athletes?

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What Do These Recommendations Mean For Non-Athletes?

Author: Dr. Stephen Chaney

fish and fish oilI have been following the research on omega-3s for athletes. But I have been reluctant to review that research in “Health Tips From the Professor” because:

  • Most of the studies are small.
  • Each study measures the effect of omega-3 supplementation on different aspects of exercise and fitness.
  • The dose of omega-3s used in the studies varies widely.
  • To the casual observer, the studies appear to come to conflicting conclusions.

I have been waiting for a respected organization to do an in-depth analysis of the published studies before commenting. The International Society of Sports Nutrition (ISSN) has just published such a study (R Jager et al, Journal of the International Society of Sports Nutrition, Issue 22 (1), 2441775, 2025) and have provided a position statement on the use of omega-3 supplements by athletes and active adults.

I would add that the ISSN is regarded as a trusted source of nutrition information for athletes.

Do Omega-3s Benefit Athletes?

Question MarkThe position of the ISSN is summarized below. What I like is they give the best recommendations based on current data and summarize the strength of the data behind each recommendation.

Statement 1: Athletes may be at higher risk of omega-3 insufficiency, and diets rich in omega-3s, including supplements, are effective for increasing omega-3 levels. In this category, they reported three key findings:

  • Omega-3s (ie EPA and DHA) are conditionally essential nutrients.
  • Fatty fish and omega-3 supplements are both effective in raising omega-3 levels.
  • Athletes belong to the groups at higher risk of omega-3 inadequacy.

My Comments:

    • This conclusion was primarily based on studies with Division I college football players. More research is needed for high-level athletes in other sports.
    • The reason for this omega-3 insufficiency was not discussed. However, I suspect it has to do with the recognition that high-level athletes need extra protein, and that fish is not usually included as a recommended source of additional protein for athletes.
    • The average Omega-3 Index for the football players was 4.4% which is considered at high risk for heart disease. The authors of the ISSN report noted that previous studies have shown that around 1.4 g/day of EPA + DHA is recommended to increase the Omega-3 Index to an optimal 8%.

Statement 2: Omega-3 supplementation, particularly EPA and DHA, has been shown to enhance Sprinterendurance capacity and cardiovascular function during aerobic-type exercise. In this category, they reported three key findings:

  • Omega-3s can improve cardiovascular dynamics during and after exercise as evidenced by enhanced red blood cell deformability, endothelial function, and heart rate recovery after exercise.
  • The incorporation of omega-3s into skeletal muscle membranes has been found to result in changes in muscle omega-3 composition, particularly in the sarcolemma, which is essential for muscle remodeling and/or regeneration after endurance exercise.
  • While these changes may help the heart pump more efficiently during exercise and muscle recover quicker after exercise, their direct impact on endurance performance remains inconsistent. More studies are needed.

My Comments:

    • These studies should be interpreted through the lens of your desired outcome. High-intensity exercise is hard on the heart.
    • If your goal is increased endurance the role of omega-3s is uncertain.
    • If your goal is to have your heart operate more efficiently during aerobic exercise, omega-3 supplementation may be beneficial.

Weight TrainingStatement 3: Omega-3 supplementation in combination with resistance training may improve strength in a dose- and duration-dependent manner. Specifically, they reported.

  • The incorporation of omega-3s into muscle cells may take a minimum of four weeks, and this is dose-dependent. It takes longer to optimize the omega-3 content in muscle cells at lower doses.
  • Once the omega-3 content of muscle cells has been optimized, it may take another three to six months until the improvement in strength plateaus.

My Comment:

    • In short, don’t expect immediate results, but omega-3 supplementation may help increase muscle strength over the long haul.

Statement 4: Omega-3 supplementation may not confer a hypertrophic benefit in young adults. [In plain English they are saying that omega-3s may not stimulate any increase in muscle mass beyond that due to exercise alone for young adults.] They went on to say:

  • More high-quality research is warranted to investigate the effects of omega-3 supplementation on body composition.

My Comments:

    • We need to remember that the ISSN recommendations are for serious athletes and may not apply to the rest of us.
    • For example, the authors state that omega-3 supplementation may enhance an increase in muscle mass…
      • When protein intake is suboptimal.
      • For older adults who are experiencing age-related loss of muscle mass.
      • For people who have previous been inactive and are just beginning an exercise program.
    • In other words, omega-3 supplements may help a lot of us non-athletes who are exercising to retain or increase muscle mass and strength.

Inflammed HeelStatement 5: Omega-3 supplementation may decrease subjective measures of muscle soreness following intensive exercise. In this category, they reported three key findings:

  • Omega-3 supplementation may attenuate indirect measures of muscle damage following intense exercise.
    • For example, when muscles are damaged, they release muscle-specific enzymes such as creatine kinase and lactate dehydrogenase into the blood. Some studies have shown that omega-3s reduce the release of these muscle enzymes following intense exercise.
  • Omega-3 supplementation is equivocal in decreasing subjective measures of muscle soreness following intense exercise.
  • Omega-3 supplementation does not decrease measures of inflammation following exercise-induced muscle damage.

My Comments:

    • Don’t count on omega-3 supplementation for reducing muscle soreness. But if you experience a decrease in muscle soreness, count it as an unexpected side benefit.
    • The lack of an effect of omega-3s at reducing inflammation post exercise may be a good thing. Some experts think that the inflammatory response plays a role in stimulating muscle repair following exercise.

Statement 6: Omega-3 supplementation can positively affect various immune cell responses in athletic populations. In this category, they reported three key findings:

  • Many athletes develop a compromised immune system due to the stress of high training volumes, which can increase the likelihood of developing acute respiratory infections that negatively impact their ability to train and compete.
  • Omega-3 supplementation can affect various immune cell responses in non-athlete, clinical, and athletic populations.
  • Many clinical studies conducted in athletic populations have indicated that omega-3 supplementation can influence the production and regulation of various inflammatory cytokines, which may lead to physiological benefits for the athletes [An example would be a reduction in exercise-induced asthma].

My Comments:

    • These recommendations are based on the effect of omega-3s on blood markers of immune health and inflammation. Clinical studies looking at the effect of omega-3s on exercise-induced respiratory infections or asthma are either nonexistent or conflicting.
    • So, if you experience decreased respiratory infections or exercise induced asthma when you add omega-3s to your exercise regimen, consider it an unexpected side benefit.

Statement 7: Omega-3 supplementation may offer neuroprotective benefits in athletes exposed to repeated head impacts. In this category, they reported three key findings:

  • Omega-3s are crucial for optimal brain development and functioning.
  • Omega-3 supplementation can increase membrane fluidity, neurotransmitter synthesis and release, and cerebral blood flow.
  • In humans, a limited amount of evidence suggests that omega-3 supplementation may offer neuroprotective benefits in athletes following repeated head impacts.

My Comments:

  • This is an important recommendation. Long-term cognitive decline, associated with repetitive traumatic brain injuries, is a serious concern for many high-impact sports. And there are no established protocols to prevent cognitive decline from occurring.
  • I have covered this in more detail in a previous issue of “Health Tips From the Professor”.

Statement 8: Omega-3 supplementation is associated with improved sleep quality. In this category, they reported three key findings:

  • Omega-3 supplementation has been linked to improved sleep quality in some studies.
  • Omega-3 supplementation may help sleep quality due to anti-inflammatory properties and effects on neurotransmitters like dopamine and serotonin, a precursor of melatonin, which helps regulate sleep-wake cycles.
  • However, inconsistency of results indicates more research is needed to fully understand the relationship between omega-3 supplementation and sleep.

My Comment:

  • If you experience improved sleep when you add omega-3s to your exercise regimen, consider it an unexpected side benefit.

Summary Of ISSN Recommendations

A strength of the ISSN recommendations is that they acknowledge where there is good agreement in the studies supporting their recommendations and where the data are scanty or conflicting. Based on the studies behind each recommendation, I would divide their recommendations into three categories.

#1: Recommendations backed by a limited number of strong studies. Confidence in these recommendations can be improved with more studies, but the recommendations are strong. These include:

  • Statement 1: Athletes are at higher risk of omega-3 insufficiency, and diets rich in omega-3s, including supplements, are effective for increasing omega-3 levels.
  • Statement 4: Omega-3 supplementation in combination with resistance training may improve strength in a dose- and duration-dependent manner.

#2: Recommendations where the evidence is weak for athletes, but valuable for non-athletes. I will discuss those in more detail below. These include:

  • Statement 2: Omega-3 supplementation has been shown to enhance endurance capacity and cardiovascular function during aerobic-type exercise.
  • Statement 3: Omega-3 supplementation may not confer a muscle hypertrophic benefit [increase in muscle mass] in young adults.

#3: Recommendations that are weak and/or conflicting. These fall in the category of “don’t count on it. But if you do experience it, consider it an unexpected side-benefit of omega-3 supplementation”. These include”

  • Statement 5: Omega-3 supplementation may decrease subjective measures of muscle soreness following intense exercise.
  • Statement 6: Omega-3 supplementation can positively affect various immune cell responses in athletic populations.
  • Statement 8: Omega-3 supplementation is associated with improved sleep quality.

Finally, the effect of omega-3 supplementation on preventing the cognitive consequences of repeated head trauma (Statement 7) is a very important topic. I have covered this in more detail in a previous issue of “Health Tips From the Professor”.

What Do These Recommendations Mean For Non-Athletes?

confusionAs their name (International Society of Sports Nutrition) suggests, their recommendations are meant primarily for athletes. But what about those of us who are not athletes but work out on a regular basis for fitness, weight management, maintaining muscle mass as we age, or other reasons?

In general, the recommendations apply equally well for athletes and non-athletes with a couple of caveats:

1) Dosage: Some of the studies with athletes were done with 3 to 6 grams/day of omega-3s. However, in most cases similar results were obtained 1-2 grams/day. Since 1-2 grams/day is enough to increase omega-3 levels to optimal for 90% of the population, I would recommend this dosage rather than the higher doses used in some of the studies with athletes.

2) Different Priorities for athletes and non-athletes: As I described earlier, this applies to two of the ISSN recommendations, namely:

  • Statement 2: Omega-3 supplementation has been shown to enhance endurance capacity and cardiovascular function during aerobic-type exercise. As I said above:
    • Young athletes are primarily interested in endurance, and the evidence for an endurance benefit for omega-3 supplementation is weak.
    • However, the rest of us are more interested in how efficiently our heart is functioning during high-intensity exercise, especially as we age. And the evidence for that benefit is strong.
  • Statement 3: Omega-3 supplementation may not confer a hypertrophic muscle benefit [increase in muscle mass] in young adults.
    • That is a true statement for young, high-performance athletes who are consuming high protein diets. For the rest of us, we need to remember the authors of the ISSN report stated that omega-3 supplementation may enhance an increase in muscle mass:
      • When protein intake is suboptimal.
      • For older adults who are experiencing age-related loss of muscle mass.
      • For people who have previous been inactive and are just beginning an exercise program.

The Bottom Line

The International Society For Sports Nutrition (ISSN) is recognized as a trusted source of nutrition advice for athletes. They recently reviewed the literature on the value of omega-3 supplementation for athletes and released a position paper with eight statements (recommendations).

I have divided these recommendations into 3 categories:

  • Recommendations backed by strong data.
  • Recommendations backed by weak data.
  • Recommendations that have different significance for high-performing athletes and the rest of us.

For more details about the ISSN recommendations and what they mean for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

 

Why Is Keeping Weight Off So Hard?

by

Can You Achieve Permanent Weight Loss? 

Author: Dr. Stephen Chaney 

Why is the dreaded yo-yo rearing its ugly head again? You tried a new diet this year, and it worked really well. The weight came off easily. But the diet is over, and the pounds are starting to creep up once again.

You are beginning to wonder if this diet was just like all the other yo-yo diets you’ve tried in the past. You are wondering whether those pounds you lost will come back and bring their friends with them. If so, you’ll be like 156 million Americans who lose weight and gain it all back each year.

And it’s so frustrating. You are trying to be good. You are still exercising and trying to eat healthily. Why isn’t it working?

Could it be that your fat cells have a memory? Could it be they like to be big and bulky with lots of stored fat? While that description is a bit fanciful, a new study (LC Hinte et al, Nature Online, 2024) suggests your fat cells may have a memory, which could explain why it is so hard to keep the weight off.

This is a highly technical study. So, before I discuss how the study was done, I should perhaps review a little bit of Biochemistry 101.

Biochemistry101: Epigenetics and Gene Activity

EpigeneticsWhat Is Epigenetics? When I was a young graduate student (which is more than just a few years ago), I was taught that all genetic information resided in our DNA. During conception, we picked up some DNA from our dad and some from our mom, and that DNA was what made us a unique individual.

In recent years, the hype has centered on DNA sequencing. It seems like everyone is offering to sequence your genome and tell you what kind of diet is best for you, what foods to eat, and what supplements to take. But can DNA sequencing fulfill those promises?

The problem is that DNA sequencing only tells you what genes you have. It doesn’t tell you whether those genes are active. Simply put, it doesn’t tell you whether those genes are turned on or turned off.

This is where epigenetics comes in. Epigenetics is the science of modifications that alter gene expression. In simple terms, both DNA and the proteins that bind to DNA can be modified. This does not change the DNA sequence. But these modifications can determine whether a gene is active (turned on) or inactive (turned off).

This sounds simple enough, but here is where it really gets interesting. These modifications are affected by our diet, our lifestyle (body weight and exercise, for example), our microbiome (gut bacteria), and our environment.

And if that weren’t complicated enough, some of these epigenetic changes (DNA modifications) can be transitory and others are long-lasting.

The authors of this study hypothesized that obesity causes long-lasting epigenetic changes to certain critical genes in our fat cells that slow metabolism and promote fat accumulation, even after we have lost weight. In other words, these epigenetic changes “prime” our fat cells to regain all the weight we’ve lost.

How Do You Measure the Effect of Epigenetic Changes? As you might expect this study measured epigenetic modifications to critical genes in fat cells. But that’s only part of the story. Epigenetic modification can turn genes on, turn them off, or have no effect on gene activity.

So, the investigators also needed to monitor the activity of the genes to determine the effect of the epigenetic modifications. Fortunately, one fact you may have learned in high school or college biology is mostly unchanged by the passage of time.

It is that the genetic sequence of DNA is translated into messenger RNA and that messenger RNA is used to code for proteins. If epigenetic modifications turned on a gene, we would expect higher levels of the corresponding messenger RNA and corresponding protein in those cells. Conversely, if epigenetic modifications turned off a gene, we would expect the opposite.

It turns out that it is much easier to measure changes in messenger RNA levels than individual protein levels that correspond to specific genes. So, the investigators used cellular messenger levels to measure the effect of epigenetic modifications on gene activity.

How Was This Study Done?

clinical studyThe investigators measured the effect of obesity and subsequent weight loss on fat cell gene expression in a limited set of human subjects and supplemented those results with a more expansive set of experiments with mice.

I don’t normally report on animal studies or very small human studies because these studies often lead to misleading results that are not supported by subsequent long-term, large clinical studies.

However, I am making an exception for this study because it leads to an interesting paradigm shift which, if true, changes the way we think about how to keep weight off long term.

Human Study: The investigators determined messenger RNA levels for key genes in fat cells from human volunteers who were:

  • At a healthy weight.
  • Obese both before and 2 years after bariatric surgery that resulted in at least 25% weight loss.

The groups were small (10-16 total), in part because obtaining fat cell samples is an invasive and painful procedure.

Mouse study: The investigators determined both messenger RNA levels and epigenic modifications for key genes in fat cells from 6-week-old male mice who were:

  • Fed either a low-fat or high-fat chow diet for 25 weeks. As expected, the mice fed the low-fat diet remained lean and the mice fed the high-fat diet became obese.
  • Subsequently, the obese mice were put on low-fat chow for 8 weeks during which time their weight returned to normal.
  • Finally, both the ‘always lean’ and ‘formerly obese’ mice were put on high-fat chow to compare how rapidly they gained weight.

What Happens To Fat Cells During Obesity And Weight Loss?

This study is best viewed as a story of what happens to fat cells during obesity and subsequent weight loss. There are two parts – what happens to human fat cells and what happens to mouse fat cells:

 Human Fat Cells: When obese individuals were compared to lean individuals:

  • Genes coding for fat storage and inflammation (which is known to be associated with obesity) were more active.
  • Fat-burning genes were less active.
  • These changes in gene expression were retained even after the obese individuals lost substantial weight through bariatric surgery.

[Note: The measurements of gene expression were based on the amount of messenger RNA produced by those genes.]

The human study had a couple of important limitations, which is why the investigators also did a similar study with mice.

#1: Because the study did not include a habitually lean group who became obese after going on a high-fat diet (no clinical review board would approve such a study), it could not determine whether the differences in gene expression were caused by the onset of obesity or whether they caused obesity.

Simply put, we know some individuals are genetically predisposed to obesity. The differences in gene expression between lean and obese individuals could have simply represented a genetic predisposition to obesity.

The mouse experiments did not suffer from that limitation because it was possible to put lean mice on a high fat diet until they became obese.

#2: The study did not measure epigenetic changes that may have caused the changes in gene expression. That is because humans are genetically heterogeneous. Consequently, you need population studies with hundreds of individuals to reliably determine epigenetic differences between groups.

The mouse experiments did not suffer from that limitation because laboratory mice are genetically homogeneous.

Mouse Fat Cells:

When the investigators looked at the physical effects of obesity:

  • When mice became obese on a high-fat diet:
    • Blood glucose levels rose.
    • Insulin levels rose, indicating the mice had become insulin resistant.
    • Fat accumulated in their livers.
  • When the obese mice lost the excess weight on a low-fat diet all these parameters returned to normal.
  • When the ‘always lean’ and ‘previously obese’ mice were put back on a high fat diet at the end of the study, the previously obese mice gained weight more quickly than the always lean mice.

In other words, mice responded to obesity in the same way that humans do except none of these effects could be explained by genetics. This strain of mice was genetically homogeneous.

When the investigators compared gene expression (as measured by messenger RNA levels) in mice who had become obese to ‘always lean’ mice:

  • Genes coding for fat storage and inflammation were more active.
  • Fat-burning genes were less active.
  • These changes in gene expression were retained even after the obese mice lost weight.

In other words, mice responded to obesity in the same ways as humans with respect to gene expression. However, in this case it was clear that obesity caused the changes in gene expression.

When the investigators looked at epigenetic modifications:

  • They identified epigenetic modifications to the regulatory regions of genes whose activity was increased or decreased when the mice became obese.
  • These epigenetic modifications were retained even after the mice lost weight.

These data suggest, but do not prove, that the epigenetic modifications were responsible for the changes in gene activity.

The authors concluded, “We show that both human and mouse adipose tissues retain transcriptional changes after appreciable weight loss.

Furthermore, we find persistent obesity induced alterations in the epigenome of mouse adipocytes that negatively affect their function and response to metabolic stimuli. Mice carrying this obesogenic memory show accelerated rebound weight gain…in response to high-fat diet feeding.

In summary, our findings indicate the existence of an obesogenic memory, largely on the basis of stable epigenetic changes, in mouse adipocytes and probably other cell types. These changes seem to prime cells for pathological response [weight gain] in an obesogenic environment, contributing to the problematic ‘yo-yo’ effect often seen with dieting.”

More simply put, the investigators concluded that obesity causes epigenetic modifications to the DNA of fat cells that prime them to regain their fat stores. They said that this may contribute to the ‘yo-yo’ effect often seen with dieting and explain why keeping weight off is so hard.

Why Is Keeping Weight Off So Hard?

Question MarkYou are not alone. You are like millions of other Americans. You lose weight effectively, but you struggle to keep it off. You just look at a donut and the fat jumps from the donut to your hips. You try to eat right, but the pounds keep creeping back on.

Experts have told us for years that our fat cells (and perhaps other cells in our body) are the culprit. Those cells have switched from a fat burning mode to a fat storage mode. There have been lots of attempts to explain that phenomenon, but my favorite is one that hypothesizes that our metabolism was designed for paleolithic times when it was either feast or famine.

Simply put, the theory is that our bodies were designed to store energy reserves in times of plenty and hold on to those energy reserves as long as possible in times of famine. Holding on to energy reserves was essential for prehistoric man to survive cold winters when food was hard to come by. And our number one energy reserve is, you guessed it, fat.

That is an appealing hypothesis, but it doesn’t tell us how our bodies manage to do that.

That’s what makes this study so intriguing. It may be wrong. It needs to be substantiated by large scale clinical trials. But the idea that epigenic changes occur during obesity and persist after substantial weight loss is novel. More importantly, it may explain the “feast or famine” response and why it is so hard to keep weight off after substantial weight loss.

Can You Achieve Permanent Weight Loss?

By now you may be thinking, “I thought my weight loss woes were due to my genetics. Now you’re telling me that they could be due to my epigenetics. Am I doubly cursed? Is there nothing I can do to keep my weight off?”

I can tell you science doesn’t have a simple answer, but there are two big clues that offer hope.

#1: Slow and steady wins the race. Obesity experts have known for years that slow weight loss often results in permanent weight loss.

  • If you are counting calories, that means a reduction of around 500 calories per week (That’s 71 calories per day, which is equivalent to one small apple, one hard-boiled egg, or 1.5 ounces of chicken breast). And a 500-calorie deficit maintained each week for a year can lead to a 20-25 pound weight loss.
  • If you are thinking of diets, it could amount to switching to a diet of unprocessed or minimally processed foods consisting of fruits, vegetables, whole grains, and primarily plant-based proteins without worrying about calories or serving sizes. Again, clinical studies show that switching from the typical American diet to this kind of diet can lead to substantial weight loss over a period of years.

Neither approach is popular in the weight loss world, but they work. Why do they work? It could be because the daily reduction in calories is so small that it never triggers the famine response.

If we look at the two parts of the study I reported on above:

  • In the human study weight loss was achieved through bariatric surgery which causes a huge reduction in caloric intake and rapid weight loss.
  • In the mouse study going from high-fat chow to low-fat chow represented a large decrease in calories. And again, weight loss was very rapid. It took the mice 25 weeks to become obese and only 4-8 weeks to lose the weight they had gained.

When viewed from this perspective, the epigenetic modifications observed after weight loss in this study may have been due to the famine response rather than a retention of the modifications observed during obesity.

And when you think about it, most popular diets feature major restrictions (calories, fats, carbs, forbidden foods, time of eating) and cause rapid weight loss. They are likely to trigger a famine response as well.

#2: The secrets of the National Weight Control Registry. There are some people who manage to keep their weight off and avoid the yo-yo effect. They don’t have any genetic or epigenetic advantage over the rest of us. They have lost weight on every diet imaginable – including rapid weight loss fad diets.

Yet they have managed to keep the weight off. What are their secrets? How did they avoid regaining their weight? How did they avoid the yo-yo diet effect?

An organization called the National Weight Control Registry was established to answer that question. It has enrolled more than 10,000 people who have lost weight and kept it off. On average people in this group have lost 66 pounds and kept it off for at least 5 years.

The National Weight Control Registry kept track of what they did to keep the weight off. Everyone’s approach was a little different, but the National Weight Control Registry summarized the ones that were most frequently mentioned. Here is what they do that you may not be doing:

#1: They consume a reduced calorie, whole food diet.

#2: They get lots of exercise (around 1 hour/day).

#3: They have internalized their eating patterns. In short, this is no longer a diet. It has become a permanent part of their lifestyle. This is the way they eat without even thinking about it.

#4: They monitor their weight regularly. When they gain a few pounds, they modify their diet until they are back at their target weight.

#5: They eat breakfast on a regular basis.

#6: They watch less than 10 hours of TV/week.

#7: They are consistent (no planned cheat days).

The good news is that participants in the National Weight Control Registry reported that while maintaining weight loss was difficult at first, it became easy after 2 years.

Of course, we don’t know whether is due to epigenic modifications being reset to “lean” by these behaviors or whether the new behaviors became automatic and overrode epigenetics.

It doesn’t matter. It means you can end the ‘yo-yo’ cycle forever. You can keep weight off, and you know how to do it.

The Bottom Line

A recent study in both humans and mice suggests that epigenetic modifications to key genes in your fat cells make it hard to keep weight off. These epigenetic changes may explain why so many people struggle with yo-yo dieting.

 

For more details on this study and how you may be able to override these epigenetic modifications and prevent weight regain read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 _____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Maternal Mortality In The United States

by

Leading Causes Of Maternal Deaths

Author: Carolyn Curtis, MSN, CNM, RN, FACNM, FAAN

Editor: Dr. Steve Chaney

Maternal Mortality In The United States

Between 2018 and 2021, the maternal mortality (death) rate in the United States nearly doubled, placing the country last among developed nations in maternal health outcomes.  The maternal mortality ratio (MMR) is a key indicator of a nation’s overall health, making this rapid increase a cause for serious concern.

Understanding Maternal Mortality

Maternal mortality refers to the number of women who die during pregnancy or within 42 days (six weeks) after childbirth for every 100,000 live births. As per the Government Accounting Office, 25% of the increase in maternal mortality from 2020 to 2021 was due to Covid-19, which contributed to the doubling of the maternal mortality ratioi.

The maternal mortality ratio is used globally to assess the state of a country’s health. A rising MMR signals the need for urgent action.

In 2022, the U.S. recorded an overall maternal mortality ratio 22.3 deaths per 100,000 live birthsii. This decreased by about 10 deaths per 100,000 from 2021 (32 deaths per 100,000 live births in 2021). However, stark racial disparities continued to exist as demonstrated through 2018 to 2021.

  • Black women: 49.5 deaths per 100,000 live births (more than 2.5 times the rate for white women)
  • White women: 19.0 deaths per 100,000 live births
  • Hispanic women: 16.9 deaths per 100,000 live births
  • Asian women: 13.2 deaths per 100,000 live births

Maternal Mortality versus Pregnancy Related Deaths

What Is The Difference?

While maternal mortality measures deaths that occur from the onset of pregnancy to six weeks post-delivery, pregnancy-related deaths extend further.  Pregnancy-related deaths are the number of deaths per 100,000 live births up to 12 months (one year) after birth or the first birthday.

Does The Age Of The Mother Make A Difference?

The age of the mother significantly affects the risk of dying during pregnancy. The ratio of deaths among women younger than 25 years of age is 14.4 deaths per 100,000 live births. Women aged 25 to 39 have a rate of 21.1/100,000 live births, while those aged 40 and older face a staggering 87.1 deaths per 100,000 live birthsiii. This means that women over 40 are dying at six times the rate of those under 25 and four times the rate of women aged 25 to 29iv.

When Are The Deaths Occurring?

Surprisingly, a little under half (47%) of maternal deaths occur during pregnancy or within the first week postpartum (Maternal Mortality).  And a little over half (53%) happen between one week and one year after childbirth or the baby’s first birthday (Pregnancy-Related Deaths).

Leading Causes Of Maternal Deaths

The primary causes of maternal mortality in the U.S. are largely preventablev. The six main causes of maternal death include:

  • Mental Health Conditions (23%) – Suicide, overdose, and substance-related poisoning are the leading causes, this affects White and Hispanic women more than Black or Asian women.
  • Hemorrhage (14%) – Severe postpartum bleeding remains one of the top causes of maternal deaths not only in the Unites States but throughout the world with Asian women being more susceptible. Hemorrhage is defined as bleeding about one half quart of blood.
  • Cardiac Conditions (13%) – Heart disease disproportionately affects Black women.
  • Blood Clots (9%) – A major contributor to maternal deaths.
  • Cardiomyopathy (9%) – A condition affecting the heart muscle, making it harder to pump blood efficiently.
  • Hypertensive Disorders of Pregnancy (7%) – relating to high blood pressure

Contributors to maternal death include familial, societal, health care system issues and one’s personal health. it is possible to reduce the risks of maternal death by understanding one’s personal health history and your family’s health history.

This information informs nutritional, behavioral and lifestyle changes that can be made prior to and during pregnancy to reduce health risks, enabling a healthier pregnancy outcome.

The Bottom Line

  • The United States has the highest maternal mortality rate amongst all developed countries in the world.
  • The maternal mortality rate in the U.S. has nearly doubled between 2018 and 2021; Covid-19 caused a 25% increase of maternal deaths from 2020 to 2021 which contributed to the doubling of maternal deaths. Black women have been disproportionately affected, with mortality rates 2.5x that of White women.
  • Women aged 40 and over die at four times the rate of women ages 25 to 39 and six times more than women under 25 years of age.
  • The leading causes of maternal deaths include mental health conditions, hemorrhage, cardiac conditions, blood clots, and cardiomyopathy— most of which are preventable.
  • Almost half of maternal deaths occur throughout pregnancy and the first week after childbirth. A little more than half of maternal deaths occur from the first week following birth up to the first year after birth.  It’s important to continue monitoring mothers with home visits once they return home from the hospital and up until one year after birth.

References

i General Accounting Office, Maternal Health: Outcomes Worsened and Disparities Persisted During the Pandemic.  Oct, 2022.

ii Hoyert DL.  Maternal mortality rates in the United States, 2022.  NCHS Health E-Stats.  2024.  DOI:https://dx.doi.org/10.15620/cdc/152992.

iii Ibid

iv Ibid.

vFour in five pregnancy related deaths in the US are preventable – https://www.cdc.gov/media/releases/2022/p0919-pregnancy-related-deaths.html.

For More Information

Feel free to visit my website, subscribe to my YouTube channel and learn more about my online coaching program, “Mastering Pregnancy and Birth”.

You-Tube Channel – Over 80 videos exploring pregnancy, labor, birth, postpartum and contraception

www.thecarabcompany.com – Website with free downloadable pregnancy and birth information

Mastering Pregnancy and Birth Coaching Program –  A program that prepares Dads and Mom’s-to-be for a healthier pregnancy and safer birth.  This course also provides information for Doulas to provide enhanced support to families.

Carolyn Curtis

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

About The Author

Carolyn Curtis, MSN, CNM, RN, FACNM, FAAN, has:

 

  • More than 40 years’ experience in the oversight of domestic and international programs and the provision of nursing and midwifery integrated service delivery in maternal child health, family planning, reproductive and women’s health care.

 

  • Twenty years’ experience in teaching, mentoring, and providing clinical oversight to undergraduate and graduate public health, medical, nursing and midwifery students.

 

About The Editor

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

How Much Should You Walk?

by

Walking Your Way To Health 

Author: Dr. Stephen Chaney 

Overweight People ExercisingYou’ve made your New Year’s resolutions. And if you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

The problem is these are all expensive options. And a good portion of that money is wasted. To put it into perspective, let’s look at some statistics

  • Around 6 million Americans buy gym memberships every January.
    • 67% of those memberships are never used.
    • For those memberships used in January, another 50% are not in use 6 months later.
  • Americans spend about 1.6 billion dollars on unused gym memberships every year.
    • And that doesn’t include those gym memberships that are only occasionally used.

If you want to get fit and healthy in the new year, perhaps you should consider a less expensive option – like walking. Your only investments are a good pair of walking shoes and a device that keeps track of the number of steps you take (eg, Fitbit, smart watch, or smart phone).

You still may give up on your New Year’s goal of getting fitter at some point. But you won’t have wasted so much money.

Of course, you probably have some questions about the benefits of walking, such as:

1) Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022) and (J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) have answered all three questions.

How Were These Studies Done?

clinical studyThe first study (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022) followed 78,500 participants (average age 61, 55% female, 97% white) enrolled in the UK Biobank study for an average of 7 years.

At the time of enrollment, each participant was given an accelerometer (a device that measures the number and frequency of steps) to wear on their dominant wrist for 24 hours/day for 7 days. The investigators used the accelerometer data to categorize several types of physical activity.

  • Daily step counts (the average number of steps per day for 7 days). These step counts were further subdivided into two categories:
    • Incidental steps (It was assumed that ˂40 steps/min represented steps taken that were incidental to normal daily activities).
    • Purposeful steps (It was assumed that ≥40 steps/min represented steps taken as part of planned exercise).
  • Stepping intensity (the highest frequency of steps/min averaged over 30 min intervals for all 7 days).

At the end of the study, each of these variables was correlated with the risk of premature deaths due to all causes, cancer, and heart disease.

The second study (J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) was similar except that it:

  • Used data from 1687 adults (average age = 55, 56% male, with diabetes or prediabetes when the study began) in the 2005-2006 National Health and Nutrition Examination Survey in the US.
  • Followed participants for 9 years instead of 7.
  • Only measured total steps/day.
  • Correlated total steps per day with premature death for participants who already had prediabetes or diabetes when they entered the study.

Walking Your Way To Health

woman walking dogStudy 1 looked at the effect of walking on health outcomes in multiple ways.

#1: Increase in number of steps/day:

  • On average study participants took an average of 7200 steps per day, but this ranged from a low of 3,200 steps/day to a high of 12,200 steps/day.
  • Each increase of 2,000 steps/day was associated with a:
    • 8% decrease in all-cause mortality.
    • 11% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.
  • Overall, increasing from 3,200 steps/day to 10,000 steps/day decreased all-cause, cancer, and heart disease mortality by around 36%.
  • There was no minimum threshold to this beneficial effect of walking on the risk of premature death.
  • The benefits of walking appeared to plateau at 10,000 steps/day.

#2: Increase in number of incidental steps/day (steps taken that are incidental to normal daily activities):

  • On average study participants took 3240 incidental steps/day, but this ranged from a low of 2,100 steps/day to a high of 4,400 steps/day.
  • Each 10% increase in incremental steps/day was associated with a:
    • 6% decrease in all-cause mortality.
    • 6% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#3: Increase in number of purposeful steps/day (steps taken as part of planned exercise):

  • On average study participants took 4,600 purposeful steps/day, but this ranged from a low of 1,600 steps/day to a high of 8,600 steps/day.
  • Each 10% increase in purposeful steps/day was associated with a:
    • 7% decrease in all-cause mortality.
    • 8% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#4: Increase in speed of walking or cadence. The measurement they used was “peak-30 cadence” – the Walking Fasthighest average steps/min during a 30-minute interval within a day:

  • On average study participants had a “peak-30 cadence” of 76 steps/min, but this ranged from a low of 47 steps/min to a high of 109 steps/min.
  • Each 10% increase in “peak-30 cadence” was associated with a:
    • 8% decrease in all-cause mortality.
    • 9% decrease in cancer mortality.
    • 14% decrease in heart disease mortality.
  • The benefits of walking rapidly (increase in “peak-30 cadence”) were in addition to the benefits seen by increasing the number of steps per day.
  • Overall, increasing from a “peak-30 cadence” of 47 steps/min to 109 steps/min decreased all-cause, cancer, and heart disease mortality by an additional 34%.
  • There was no minimum threshold to this beneficial effect of increasing “peak-30 cadence” (the speed of walking) on the risk of premature death.
  • The benefits of increasing “peak-30 cadence” appeared to plateau at 100 steps/min.

strong heart#5 Effect of walking on the prevention of heart disease and cancer: The investigators measured this by looking at the effect of walking on the “incidence” of heart disease and cancer (defined as new diagnoses of heart disease and cancer) during the study. They found.

  • Each 2,000-step increase in the total number of steps/day decreased the risk of developing heart disease and cancer by 4% during this 7-year study.
  • Each 10% increase in the number of purposeful steps/day decreased the risk of developing heart disease and cancer by 4% during this study.
  • Each 10% increase in “peak-30 cadence” decreased the risk of developing heart disease and cancer by 7% during this study.

The authors concluded, “The findings of this population-based…study of 78,500 individuals suggest that up to 10,000 steps/day may be associated with a lower risk of mortality and cancer and CVD incidence. Steps performed at a higher cadence may be associated with additional risk reduction, particularly for incident disease.”

Study 2 extended these findings to diabetes. They started with participants that had either prediabetes or diabetes diabetesand followed them for 9 years. They found that:

  • Study participants with prediabetes ranged from a low of 3,800 steps/day to a high of 10,700 steps/day.
    • Prediabetic participants walking 10,700 steps/day were 25% less likely to die during the study than participants walking only 3,800 steps/day.
  • Study participants with diabetes ranged from a low of 2,500 steps/day to a high of 10,200 steps/day.
    • Diabetic participants walking 10,200 steps/day were also 25% less likely to die during the study than participants walking only 2,500 steps/day.
  • Even small increases in the number of steps per day decreased the risk of premature death for both prediabetic and diabetic participants.
  • Once again, 10,000 steps/day appeared to be the optimal dose to lower the risk of premature death for both diabetic and prediabetic patients.

The authors of this study concluded, “Accumulating more steps/day up to ~10,000 steps/day may lower the risk of all-cause mortality of adults with prediabetes and diabetes.”

How Much Should You Walk?

Walking CoupleThat was a lot of information. You are probably wondering what it means for you. Let’s start with the big picture:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.

In other words, simply walking more and walking faster can have a significant effect on your health. I am not recommending walking as your only form of exercise. I’m just saying not to consider it inferior to other forms of exercise.

  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.

In other words, you don’t need to speed walk 10,000 steps/day to reap a benefit from walking. Even small increases are beneficial. That’s good news for those of you who may not be able to speed-walk long distances. It also means that if you are a couch potato, you don’t need to attempt 10,000 steps at high speed from day 1. You can work up to it gradually.

  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).

That’s good news for those of you who may not have time for long walks. It also means that advice like “park your car at the far end of the parking lot and walk” or “take the stairs rather than the elevator” can have a meaningful impact on your health.

  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

That means once you get to those levels, it’s time to consider adding other kinds of exercise to your regimen. More and faster walking may offer little additional benefit.

Finally, in the words of the authors, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

The Bottom Line 

You’ve made your New Year’s resolutions. And if you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

If you want to get fit and healthy in the new year, perhaps you should also consider a less expensive option – like walking.

Of course, you probably have some questions about the benefits of walking, such as:

  1. Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies have answered all three questions. They found:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.
  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.
  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).
  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

In the words of the authors of these studies, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

For more details on these studies and what they mean for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 _____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 ______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Relief From Tension Headache Pain

by

Which Muscles Cause Tension Headaches?

Author: Julie Donnelly, LMT – The Pain Relief Expert

Editor: Dr. Steve Chaney

Topic Of The Month – Tension Headaches

headacheLately a lot of people have been coming to my office complaining of headaches that have plagued them for a long time…in one case for years!

This woman had been everywhere and had every test that the medical world could offer.  Nothing showed why she had these terrible headaches.  At one point she told me the pain was a 10 on a scale of 1-10.  Imagine how terrible it was for her to suffer every day from such a crippling condition.  My heart went out to her!

Fortunately, her problem was caused by muscles, the one thing that most of the medical world doesn’t consider when looking for a solution to pain.

In fact, if you watched my TED talk: The Pain Question No One is Asking, you may have already heard me talk about this missing link. (If you haven’t heard my TED talk, go to YouTube and enter: Julie Donnelly, Pain and I’ll pop up.)

Let’s talk about muscles and why they will cause headaches (and a whole lot more!).

Which Muscles Cause Tension Headaches?

While there are many causes for headaches, such as stress, anxiety, depression, head injury, or anxiety, and life-threatening causes we won’t go into here, one type of headache that is caused by muscular tension is known as a muscle contraction tension headache.

As shown in the graphics above, muscle spasms (colored circles) will refer pain to your head, even when you don’t feel any discomfort where the spasm is actually occurring.

(In this article I will focus on treatments for pain caused by the levator scapulae and trapezius muscles).

Muscles in the neck and scalp can become tense or contract in response to stress, depression, or anxiety, leading to tension headaches.  Fortunately, in many cases, simply pressing on the trigger points (the colored circles) will release the tension being felt in your head.

To prevent tension headaches, it is important to maintain good posture, practice relaxation techniques, and use a pillow that keeps your head, neck, and spine in a horizontal plane while you sleep.

Relief From Tension Headache Pain

There are too many treatments for headaches to include all of them in this newsletter.  If you want to know them, I suggest you get one of my books, especially Treat Yourself to Pain-Free Living or The Pain-Free Athlete.

Meanwhile, I want to share an important Julstro self-treatment that you may find works well for tension headaches:

 

Place a ball such as the Perfect Ball (shown in picture) or a tennis ball, on the top of your shoulder.

 

 

 

Lean into the corner of a wall, as shown.

 

headache relief shoulder muscle pressure using wall

Keep your head close to the wall to prevent the ball from slipping and landing on the floor.

 

Bend at your hips so your upper body goes up and down, causing the ball to roll along the top of your shoulder. This will treat both the levator scapulae and trapezius muscles – both are key muscles for tension headaches.

 

 

Be gentle with this treatment as it will cause pain to be felt in your head as you are doing the treatment.  Only use enough pressure that it “hurts so good.”

Do 5-6 passes on each side.  It can be repeated often during the day but give a little time between each session to allow the muscle to relax.

Drink a LOT of water so the acid that you’re pressing out of the muscle will get flushed out of your body.

This may look a bit confusing, but it’s simple when you follow the directions.  And the best part is, IT WORKS!

How to Learn the Other Treatments for Headaches

If you go to www.FlexibleAthlete.com you can read a lot more about muscles and pain.  You will also find my books and other self-treatment tools by pressing on Shop.

Wishing you well,

Julie Donnelly

www.FlexibleAthlete.com

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 ______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 ______________________________________________________________________

About The Author

Julie DonnellyJulie Donnelly has been a licensed massage therapist since 1989, specializing in the treatment of chronic pain and sports injuries. The author of several books including Treat Yourself to Pain-Free Living, The Pain-Free Athlete, and The 15 Minute Back Pain Solution.

Julie has also developed a proven self-treatment program for the symptoms of carpal tunnel syndrome.

She has a therapy practice in Sarasota, Florida, and she travels around the USA to teach massage and physical therapists how to do the Julstro Method, and she also teaches self-treatment clinics to anyone interested in taking charge of their own health and flexibility.

She may be reached at her office: 919-886-1861, or through her website: www.FlexibleAthlete.com

About The Editor

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Are Our Teens Getting Sicker?

by

What Does This Mean For Us?

Author: Dr. Stephen Chaney

High Blood SugarThe increase of prediabetes and type 2 diabetes in the US adult population has been well documented. And these conditions have severe health consequences.

  • Nearly 70% of people with prediabetes will go on to develop type 2 diabetes.
    • Without a change in lifestyle and/or medical intervention, many people with prediabetes develop type 2 diabetes within 5 years.
  • Type 2 diabetes is highly correlated with increased risk for heart disease and stroke, vision loss, kidney disease, nerve damage, and cognitive decline.
  • And as we learned during COVID, diabetes suppresses the immune system, making us much more likely to die from viral infections ranging from flu to RSV and coronaviruses like SARS-CoV-2.

Because both prediabetes and type-2 diabetes are highly correlated with obesity, the US Preventative Services Task Force has recently recommended regular screening of adults aged 35-70 who are overweight or obese for prediabetes and type-2 diabetes.

But what about our teenagers? Are they at risk? Should they be screened also? Recent reports have documented an alarming increase in overweight and obesity in this population group.

The prevalence of type-2 diabetes is low in this group, but previous studies have reported that approximately 1 in 5 US teenagers have prediabetes. Is this a ticking time bomb that will affect their health as adults? More importantly, is the prevalence of prediabetes getting worse, just as it is for the adult population?

The expectation is that the prevalence of prediabetes in US teens is increasing, just as it is for US adults. But scientists and health organizations like the Preventive Services task force require hard data, not just expectations.

So, the study (J Liu et al, JAMA Prediabetes, 176: 608-610, 2022) I will describe today was designed to determine the prevalence trend over the past 20 years for prediabetes in US teenagers.

How Was The Study Done?

clinical studyThe study used data from the NHANES database from 1999 to 2018. NHANES (National Health and Nutritional Examination Survey) is a program administered by the CDC that collects health and nutrition information from adults and children in the United States on a biennial basis.

Among the data collected are demographic information (sex, age, race, economic status, etc.), physical exam information (BMI, blood chemistry, etc.), and health information (prediabetes, diabetes, etc.).

To have enough participants in each time period for statistically significant results, the data were combined for each two consecutive 2-year surveys. (For example, the 2000-2001 and 2001-2002 NHANES surveys were combined into a single dataset from 1999 to 2002.)

The time periods included in this study were 1999-2002, 2003-2006, 2007-2010, 2011-2014, and 2015-2018. A total of 6598 teenagers were included in this study, for an average of around 1,300 per time-period.

The main comparison was prediabetes prevalence among US teens in each time period. The study also looked at the effect of obesity and various sociodemographic classifications on prediabetes prevalence in teens.

Are Our Teens Getting Sicker?

diabetesWhen the 2015-2018 time period was compared to the 1999-2002 time period, the prevalence of prediabetes:

  • Increased from 11.6% to 28.2% – a 2.43-fold increase.

When broken down by age groups, the increase was:

  • 2.35-fold for ages 12-15.
  • 2.56-fold for ages 16-19.

When broken down by gender, the increase was:

  • 2.76-fold for females.
  • 2.30-fold for males.

When broken down by race and ethnicity, the increase was:

  • 2.10-fold for Hispanics.
  • 2.76-fold for Blacks.
  • 2.33-fold for Whites.

None of these differences were statistically significant, but they might have been had the sample size been larger.

In short, there has been more than a 2-fold increase in the prevalence of prediabetes in US teenagers over the last 20 years. And this increase was seen in young teenagers, older teenagers, male and female teenagers, and in every racial and ethnic category surveyed.

Why Is Prediabetes Increasing In Our Teens?

QuestionsKnowing the trend is important. But if you want to reverse the trend, it’s much more important to know what is causing it.

Of course, obesity is an obvious villain. Obesity is highly associated with prediabetes and type 2 diabetes, and we know that obesity is increasing in our teens. The data from this study suggests that obesity may contribute to the increase in prediabetes prevalence. But it’s not likely to be the sole cause.

For example:

  • Obesity in our teens has only increased 1.3-fold over the last 20 years.
  • More importantly, the difference in prediabetes prevalence between normal weight and overweight teens was not significant in this study.

The authors of this study also found no significant effect of educational level of the parents, family income level, or food security on the increased prevalence of prediabetes prevalence in teens.

So, what else might be contributing to the increased prevalence of prediabetes in our teens? I have two suggestions:

  • Decreased physical activity. Teens today are spending more hours staring at screens and less time exercising. Lack of exercise contributes to obesity, but there is also emerging evidence that it may independently contribute to diseases like prediabetes and diabetes.
  • Increased junk food consumption. Teenager’s diets have never been great, but multiple studies have shown that consumption of highly processed food has skyrocketed over the past 20 years.

Obviously, more work needs to be done on proving the causes of increased prediabetes prevalence in our teens, but we know enough already to start making some needed changes.

What Does This Study Mean For Us?

If you are a parent or grandparent, this study is a wake-up call. It’s not that we didn’t already suspect it was happening. After all, the increasing prevalence of type 2 diabetes in young US adults had to come from somewhere.

But this study makes it clear that prediabetes is increasing at an alarming rate in our teenage children (and grandchildren). This is a ticking time bomb.

As I said above, prediabetes leads to diabetes. And diabetes leads to heart disease and other debilitating diseases. Unless we reverse this trend, we may be dooming our teens to poor health and a shortened lifespan as adults.

So, the important questions become, “What can we do about it?” and “What can we do to reverse this trend?”

The top three things we can do are clear. We need to encourage our teens to:

  • Exercise more. Only 1 in 4 high school students get the recommended amount of daily activity.
  • Eat a healthier diet. Today more than 2/3 of the calories our teens consume come from ultraprocessed foods.

And we know the changes they need to make. Previous studies have shown that whole food, primarily plant-based diets reduce the risk of developing prediabetes and type 2 diabetes and can even reverse both conditions as effectively as medications.

  • Maintain a healthier weight. The prevalence of obesity in our teens has increased dramatically in the last 40 years. Of course, the secret is that if they get the diet and exercise part right, weight control is much easier.

But none of these changes are easy. This can’t be a, “Do as I say, not as I do” change. This needs to be a whole family change. We need to set the example.

Of course, I know some teens like to rebel against anything their parents do or recommend. We had a teenager once.

Setting the example doesn’t necessarily mean they will accept it right away. But with time they may come around. They are listening to what you say and watching what you do even when they are doing the opposite.

And I can guarantee if you aren’t willing to make these changes, they won’t be either.

The Bottom Line

A recent study looked at the prevalence of prediabetes in US teenagers over the past 20 years. The results were alarming.

  • The prevalence of prediabetes in US teens has more than doubled over the past 20 years.
  • In 2018, the last year in this study, the prevalence of prediabetes was in the 25-30% range.
  • The increased prevalence of diabetes was independent of gender, income, food security, ethnicity, and education level of the parents.

If you are a parent or grandparent, this is a ticking time bomb because 70% of people with prediabetes go on to develop type 2 diabetes within the next 5 years. And type 2 diabetes dramatically increases the risk of heart disease, stroke, kidney disease, vision loss, and cognitive decline. We may be dooming our teens to poor health and a shortened life span as adults.

For more details about this study, the causes of the increased prevalence of prediabetes in teens, and what you can do to reverse this trend for your teens, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 _____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 _____________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Are Weekend Warriors As Healthy As Regular Exercisers?

by

What Does This Study Mean For You? 

Author: Dr. Stephen Chaney 

It’s a new year and once again you have set New Year’s goals. If you are like millions of Americans your top 3 goals are probably to eat healthier, exercise more, and lose weight – not necessarily in that order. Now comes the hard part:

  • Setting realistic weight loss goals and developing strategies for achieving those goals.
  • Deciding on food choices and eating behaviors you will change.
  • Deciding on what kind of exercises you will do and how often you will do them.

With respect to exercise, the consensus is clear. We should be aiming for ≥150 minutes of moderate-to-vigorous physical activity per week. But how often should we be exercising? Here the answer is a bit murkier.

Most experts recommend we exercise 3-5 times a week. But that advice doesn’t work for everyone. For some people, their work schedule and family responsibilities make it difficult to find time during the week to exercise.

However, many of these individuals are very active during the weekend with things like yard work, organized sports, long hikes, and/or cycling excursions. We refer to these people as Weekend Warriors.

If you are one of these individuals, you are probably wondering if that’s enough. Are weekend warriors as healthy as people who exercise every day, or must you squeeze some exercise into your busy week?

Some recent studies have suggested that frequency of exercise is not important as long as you exceed the magical 150 minutes per week. However, each of these studies had limitations. For example:

  • They only looked at a few kinds of exercise and a few diseases.
  • Some studies depended on self-assessments of exercise frequency and intensity, which are notoriously unreliable.

The study (Circulation, 150: 1236-1247, 2024) I am reviewing today compares the health outcomes of weekend warriors and people who exercise throughout the week and was designed to eliminate the limitations of previous studies.

How Was This Study Done?

clinical studyThe authors used data obtained from the UK Biobank Study, which is an ongoing study following the health outcomes of individuals from all corners of the United Kingdom who enrolled in the study between 2006 and 2010. Each participant underwent a health assessment when they enrolled.

This study used data from a subset of 89,573 participants (average age 62, percent women 56%) who wore a wrist accelerometer to measure activity levels for one week between June 8, 2013, and December 30, 2015. The accelerometer measured activity levels every 5 seconds, so it was able to record the intensity, frequency, and duration of exercise during the week.

Participants were divided into three groups based on their accelerometer measurements:

  • Inactive: <150 minutes per week of moderate-to vigorous physical activity (34% 0f participants).
  • Weekend Warriors: ≥150 minutes per week of moderate-to vigorous physical activity with the bulk of the activity spread over 1-2 days (42% of participants).
  • Regular Exercisers: ≥150 minutes per week of moderate-to vigorous physical activity with the activity spread over multiple days (24% of participants).

The participants were followed for an average of 6.3 years with 94% of participants having >5 years of follow up. The outcome was frequency of incident diseases (diseases that were not present during the accelerometer measurements but were diagnosed during the follow-up period).

Because the United Kingdom is one of the countries with a “Big Brother knows all” health care system, the investigators were able to correlate the exercise levels of each participant with 678 diseases and health conditions. The study compared the disease incidence of weekend warriors with the inactive group, regular exercisers with the inactive group and weekend warriors with the regular exercisers.

Are Weekend Warriors As Healthy As Regular Exercisers?

Let me start with the big picture and then I will give some specific statistics.

  • Both the weekend warrior and regular exercise patterns were associated with lower risk for >200 diseases compared to the inactive group.
    • For both exercise patterns there were a small number of associations with higher disease risks – primarily musculoskeletal disorders and dermatological conditions (think sports injuries and excessive sun exposure).
    • However, both exercise patterns were associated with a lower risk of over a dozen musculoskeletal conditions such as osteoarthritis and spinal degenerative spinal conditions.
  • While both exercise patterns were associated with the risk of >200 diseases, the risk reduction was greatest for cardiometabolic diseases associated with obesity. For example, the risk reduction for:
    • Hypertension was reduced by 23% and 28%, respectively, for weekend warriors and regular exercisers.
    • Diabetes was reduced by 43% and 46%, respectively, for weekend warriors and regular exercisers.
    • Obesity was reduced by 45% and 56%, respectively, for weekend warriors and regular exercisers.
    • Sleep apnea (which is associated with obesity) was reduced by 43% and 51%, respectively, for weekend warriors and regular exercisers.
    • Chronic renal failure (Chronic renal failure can be caused by a fatty liver, which is associated with obesity) was reduced by 36% and 35%, respectively, for weekend warriors and regular exercisers.
    • Gallstones (which are associated with obesity) were reduced by 36% and 43%, respectively, for weekend warriors and regular exercisers.
  • You will notice that risk reduction was generally greater for regular exercisers than for weekend warriors. That is because the regular exercisers averaged higher weekly totals for moderate-to-vigorous activity levels than weekend warriors. When the two groups were compared at the same weekly activity level, there was no significant difference between the two groups.

What Did The Authors Say About This Study?

The authors discussed the limitations of the study in detail in the discussion section of their paper. The three biggest limitations are:

  • This study measured associations. It does not prove cause and effect.
  • The study only measured exercise patterns and intensities for one week. Some participants may have changed their exercise patterns during the follow-up period.
  • The wrist accelerometer used in this study has been validated for a variety of aerobic activities. It may be less accurate at measuring some strength training exercises. And it will be unable to measure isometric exercises, which have been shown to have some cardiometabolic health benefits.

However, this is a very large, well-designed study which is consistent with several earlier studies.

The authors also expanded on the significance of their findings with these comments:

1) “Efforts to optimize physical activity may be expected to have wide-ranging health benefits that extend beyond previously published associations with cardiovascular disease…We observed strong associations between physical activity and lower risk of up to 264 diseases.”

2) “Our results suggest that the achievement of guideline-adherent physical activity volumes [≥150 minutes per week of moderate-to-vigorous activity] is the key factor relevant to incident disease risk, as opposed to the pattern by which physical activity may be accrued…We did not identify a single condition for which risk appeared substantially different for one pattern versus the other.”

3) “Although we noted beneficial associations across a wide variety of diseases, our findings suggest that physical activity may be particularly effective for modifying risk of cardiometabolic conditions, including hypertension, obesity, diabetes, and sleep apnea.”

The authors concluded, “Achievement of measured physical activity volumes consistent with guideline recommendations [≥150 minutes per week of moderate-to-vigorous activity] is associated with lower risk of >200 diseases, with prominent effects on cardiometabolic conditions. Associations appear to be similar whether the physical activity follows a weekend warrior pattern or is spread more evenly throughout the week.”

What Does This Study Mean For You?

QuestionsThis study has three major take-home messages:

1) If you weren’t already motivated to increase your exercise levels in 2025, this study is a wake-up call. You already know that exercise improves your mood, makes weight control easier, and reduces the risk of major diseases like diabetes, hypertension, and heart disease.

This study just added another 200 reasons to increase your exercise levels. (If you want to know the 200+ diseases that are positively impacted by exercise, read the study.

2) If you are someone whose schedule makes it difficult to find time during the week, this study is good news. This study suggests that weekend warriors can be as fit and healthy as people who exercise daily. However, there are a couple of important caveats:

    • This study used a wrist accelerometer, so it was able to select only those weekend warriors whose total activity exceeded 150 minutes of moderate-to-vigorous activity. Unfortunately, many weekend warriors overestimate how much exercise they get during the weekend. For example:
      • Mowing the lawn is exercise, but the amount of exercise you get is vastly different if you use a riding mower instead of a push mower.
      • Weekend sports are a fun way to exercise, but the amount of exercise you get from an hour of soccer is probably different from an hour of softball.
    • I could go on, but you get the idea. If you choose the weekend warrior route, be realistic about the amount of exercise you are getting.

3) This study found that people who exercised often during the week were likely to accumulate higher weekly totals of activity than weekend warriors. Simply put, it is easier to accumulate higher exercise totals when you exercise more frequently.

So, even if your schedule is busy, it’s worthwhile to try and find some time to exercise during the week rather than limiting all your exercise to the weekend.

The Bottom Line

A recent study asked whether weekend warriors got the same benefits from exercise as people who exercised on multiple days during the week (regular exercisers). The key findings from the study were:

  • Weekly exercise levels of ≥150 minutes of moderate-to-vigorous activity were associated with reduced risk of over 200 diseases.
  • The reduction in risk was greatest for obesity and cardiometabolic diseases like diabetes and hypertension.
  • Once the ≥150 minutes of moderate-to-vigorous activity was reached, there was no significant difference in risk reduction between the weekend warrior and regular exercise patterns of activity.

For more details on this study and what this means for you read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 ______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance 

___________________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

 

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Health Tips From The Professor