Is HDL Good For Your Heart?

Is Everything You Knew About HDL Wrong?

Author: Dr. Stephen Chaney 

HDL CHolesterolIn last week’s “Health Tips From the Professor” I 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.

Last week I shared a study that disproved the paradigm that low to moderate alcohol consumption is healthier than total abstinence. This week I 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 underlying HDL/heart health paradigm weren’t true? These hypotheses would be like the parable of a house built on a foundation of sand. The paradigm will be washed away as soon as it is critically tested.

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

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.

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 16 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.

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 likely 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”. I described the term and how it affects clinical studies in last week’s article. 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 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.Heart Disease Study

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:

  • 7.1% reduction in heart disease events (both heart disease deaths and non-fatal heart attacks).
  • 7.2% reduction in heart disease deaths.
  • 4.4% 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.

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 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 HDL/heart health paradigm – 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

Can Healthy Eating Help You Lose Weight?

Who Benefits Most From A Healthy Diet?

Author: Dr. Stephen Chaney 

fad dietsFad diets abound. High protein, low carb, low fat, vegan, keto, paleo – the list is endless. They all claim to be backed by scientific studies showing that you lose weight, lower your cholesterol and triglycerides, lower your blood pressure, and smooth out your blood sugar swings.

They all claim to be the best. But any reasonable person knows they can’t all be the best. Someone must be lying.

My take on this is that fad diet proponents are relying on “smoke and mirrors” to make their diet look like the best. I have written about this before, but here is a brief synopsis:

  • They compare their diet with the typical American diet.
    • Anything looks good compared to the typical American diet.
    • Instead, they should be comparing their diet with other weight loss diets. That is the only way we can learn which diet is best.
  • They are all restrictive diets.
    • Any restrictive diet will cause you to eat fewer calories and to lose weight.
    • As little as 5% weight loss results in lower cholesterol & triglycerides, lower blood pressure, and better control of blood sugar levels.

Simply put, any restrictive diet will give you short-term weight loss and improvement in blood parameters linked to heart disease, stroke, and diabetes. But are these diets healthy long term? For some of them, the answer is a clear no. Others are unlikely to be healthy but have not been studied long term. So, we don’t know whether they are healthy or not.

What if you started from the opposite perspective? Instead of asking, “Is a diet that helps you lose weight healthy long term?”, what if you asked, “Can healthy eating help you lose weight?” The study (S Schutte et al, American Journal of Clinical Nutrition, 115: 1-18, 2022) I will review this week asked that question.

More importantly, it was an excellent study. It compared a healthy diet to an unhealthy diet with exactly the same degree of caloric restriction. And it compared both diets to the habitual diet of people in that area. This study was performed in the Netherlands, so both weight loss diets were compared to the habitual Dutch diet.

How Was The Study Done?

clinical studyThis was a randomized controlled trial, the gold standard of clinical studies. The investigators recruited 100 healthy, abdominally obese men and women aged 40-70. At the time of entry into the study none of the participants:

  • Had diabetes.
  • Smoked
  • Had a diagnosed medical condition.
  • Were on a medication that interfered with blood sugar control.
  • Were on a vegetarian diet.

The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

The study lasted 12 weeks. The participants met with a dietitian on a weekly basis. The dietitian gave them the foods for the next week and monitored their adherence to their assigned diet. They were advised not to change their exercise regimen during the study.

At the beginning and end of the study the participants were weighed, and cholesterol, triglycerides, and blood pressure were measured.

Can Healthy Eating Help You Lose Weight?

Vegetarian DietTo put this study into context, these were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants lost significant weight on both calorie-restricted diets compared to the group that continued to eat their habitual diet.
    • That is not surprising. Any diet that successfully restricts calories will result in weight loss.
  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).
  • Participants on the high-nutrient quality diet lost 50% more inches in waist circumference than participants on the low-nutrient-quality diet (1.8 inches compared to 1.2 inches).
    • This is a direct measure of abdominal obesity.

When the investigators measured blood pressure, fasting total cholesterol levels, and triglyceride levels:Heart Healthy Diet

  • These cardiovascular risk factors were significantly improved on both diets.
    • Again, this would be expected. Any diet that causes weight loss results in an improvement in these parameters.
  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

Who Benefits Most From A Healthy Diet?

None of the participants in this study had been diagnosed with diabetes when the study began. However, all of them were middle-aged, overweight, and had abdominal obesity. That means many of them likely had some degree of insulin resistance.

Because of some complex metabolic studies that I did not describe, the investigators suspected that insulin resistance might influence the relative effectiveness of the two energy-restricted diets.

To test this hypothesis, they used an assay called HOMA-IR (homeostatic model assessment of insulin resistance). Simply put, this assay measures how much insulin is required to keep your blood sugar under control.

They used a HOMA-IR score of 2.5 to categorize insulin resistance among the participants.

  • Participants with a HOMA-IR score >2.5 were categorized as insulin-resistant. This was 55% of the participants.
  • Participants with a HOMA-IR score ≤2.5 were categorized as insulin-sensitive. This was 45% of the participants.

When they used this method to categorize participants they found:

  • Insulin-resistant individual lost about the same amount of weight on both diets.
  • Insulin-sensitive individuals lost 66% more weight on the high-nutrient-quality diet than the low-nutrient-quality diet (21.6 pounds compared to 13.0 pounds).

The investigators concluded, “Overweight, insulin-sensitive subjects may benefit more from a high- than a low-nutrient-quality energy-restricted diet with respect to weight loss…”

What Does This Study Mean For You?

Questioning WomanSimply put this study confirms that:

  • Caloric restriction leads to weight loss, and…
  • Weight loss leads to improvement in cardiovascular risk factors like total cholesterol, triglycerides, and blood pressure.
    • This is not new.
    • This is true for any diet that results in caloric restriction.

This study breaks new ground in that a high-nutrient quality diet results in significantly better:

  • Weight loss and…
  • Reduction in cardiovascular risk factors…

…than a low-nutrient quality diet. As I said above, the distinction between a “high-nutrient-quality” diet and a “low-nutrient-quality” diet may not be what you might have expected.

  • Both diets were whole food diets. Neither diet allowed sodas, sweets, and highly processed foods.
  • Both included fruits, vegetables, grains, and lean meats.
  • Both reduced caloric intake by 25%.
    • If you want to get the most out of your weight loss diet, this is a good place to start.

In this study the investigators designed their “high-nutrient-quality” diet so that it contained:

  • More plant protein in the form of soy protein.
    • In this study they did not reduce the amount of animal protein in the “high-nutrient-quality” diet. They simply added soy protein foods to the diet. I would recommend substituting soy protein for some of the animal protein in the diet.
  • More fiber.
    • The additional fiber came from substituting whole grain breads and brown rice for refined grain breads and white rice, adding soy protein foods, and adding an additional serving of fruit.
  • More healthy fats (monounsaturated and omega-3 fats).
    • The additional omega-3s came from adding a fish oil capsule providing 700mg of EPA and DHA.
  • Less simple sugars. While this study focused on fructose, their high-nutrient-quality diet was lower in all simple sugars.

ProfessorAll these changes make great sense if you are trying to lose weight. I would distill them into these 7 recommendations.

  • Follow a whole food diet. Avoid sodas, sweets, and highly processed foods.
  • Include all 5 food groups in your weight loss diet. Fruits, vegetables, whole grains, dairy, and lean proteins all play an important role in your long-term health.
  • Eat a primarily plant-based diet. My recommendation is to substitute plant proteins for at least half of your high-fat animal proteins. And this study reminds us that soy protein foods are a convenient and effective way to achieve this goal.
  • Eat a diet high in natural fibers. Including fruits, vegetables, whole grains, beans, nuts, seeds, and soy foods in your diet is the best way to achieve this goal.
  • Substitute healthy fats (monounsaturated and omega-3 fats) for unhealthy fats (saturated and trans fats) in your diet. And this study reminds us that it is hard to get enough omega-3s in your diet without an omega-3 supplement.
  • Reduce the amount of added sugar, especially fructose, from your diet. That is best achieved by eliminating sodas, sweets, and highly processed foods from the diet. I should add that fructose in fruits and some healthy foods is not a problem. For more information on that topic, I refer you to a previous “Health Tips” article .
  • Finally, I would like to remind you of the obvious. No diet, no matter how healthy, will help you lose weight unless you cut back on calories. Fad diets achieve that by restricting the foods you can eat. In the case of a healthy diet, the best way to do it is to cut back on portion sizes and choose foods with low caloric density.

I should touch briefly on the third major conclusion of this study, namely that the “high-nutrient quality diet” was not more effective than the “low-nutrient-quality” diet for people who were insulin resistant. In one sense, this was not news. Previous studies have suggested that insulin-resistant individuals have more difficulty losing weight. That’s the bad news.

However, there was a silver lining to this finding as well:

  • Only around half of the overweight, abdominally obese adults in this study were highly insulin resistant.
    • That means there is a ~50% chance that you will lose more weight on a healthy diet.
  • Because both diets restricted calories by 25%, insulin-resistant individuals lost weight on both diets.
    • That means you can lose weight on any diet that successfully reduces your caloric intake. That’s the good news.
    • However, my recommendation would still be to choose a high-nutrient quality diet that is designed to reduce caloric intake, because that diet is more likely to be healthy long term.

The Bottom Line 

A recent study asked, “Can healthy eating help you lose weight?” This study was a randomized controlled study, the gold standard of clinical studies. The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

These were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).

When the investigators measured cardiovascular risk factors at the end of 12 weeks:

  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

For more details on this study, what this study means for you, and my 7 recommendations for a healthy weight loss diet, 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.

Omega-3s Reduce Preterm Births

Do Omega-3s Make For A Healthy Pregnancy?

Author: Dr. Stephen Chaney 

omega-3s during pregnancy is healthyThe role of omega-3s on a healthy pregnancy has been in the news for some time. Claims have been made that omega-3s reduce preterm births, postnatal depression, and improve cognition, IQ, vision, mental focus, language, and behavior in the newborn as they grow.

The problem is that almost all these claims have been called into question by other studies. If you are pregnant or thinking of becoming pregnant, you don’t know what to believe.

  • Should you eat more fish?
  • Should you take omega-3 supplements?
  • Or should you just ignore the claims about omega-3s and a healthy pregnancy?

These are not trivial questions. Let’s consider preterm births as an example. The medical profession has made enormous advances in keeping premature babies alive. However, premature babies are still at higher risk of several health conditions including:

  • Visual impairment.
  • Developmental Delay.
  • Learning difficulties.

Plus, it is expensive to keep premature babies alive. One recent study estimated that increasing omega-3 intake during pregnancy could reduce health care costs by around $6 billion in the United Stated alone.

Unfortunately, it’s not just omega-3s and pregnancy. The same is true for almost all nutritional health claims. One day a study comes out claiming that nutrient “X” cures some disease or has some miraculous benefit. The bloggers and news media hype that study. Suddenly you see that health claim everywhere. It becomes so omnipresent that you are tempted to believe it must be true.

But wait. A few months later another study comes to opposite conclusion. Now the media is telling you that health claim is false. The months come and go, and new studies keep coming out. Some support the health claim. Others refute it.

Pretty soon the nutrition headlines just become “noise”. You don’t know what to believe. If you want the truth, “Who ya gonna call?”

Who Ya Gonna Call?

ghost bustersIt’s not Ghostbusters. It not Dr. Strangelove’s health blog. It’s a group called the Cochrane Collaboration.

The Cochrane Collaboration consists of 30,000 volunteer scientific experts from across the globe whose sole mission is to analyze the scientific literature and publish reviews of health claims so that health professionals, patients, and policy makers can make evidence-based choices about health interventions.

The Cochrane Collaboration reviews all the relevant studies on a topic, exclude those that are biased or weak, and make their recommendations based on only the strongest studies. Their reviews are considered the gold standard of evidence-based medicine.

If you are of a certain age, you may remember that TV commercial “When EF Hutton talks, people listen.” It is the same with the Cochrane Collaboration. When they talk, health professionals listen.

This week we will examine the Cochrane Collaboration’s review titled “Omega-3 Fatty Acid Addition During Pregnancy”.

How Was The Study Done?

Clinical StudyFor this analysis the Cochrane Collaboration reviewed 70 randomized controlled trials which compared the effect of added omega-3s on pregnancy outcomes with either a placebo or a diet no added omega-3s. These trials included almost 19,927 pregnant women.

In one sense, Cochrane reviews are what is called a “meta-analysis”, in which data from numerous studies are grouped together so that a statistically significant conclusion can be reached. However, Cochrane Collaboration reviews differ from most meta-analyses found in the scientific literature in a very significant way.

Many published meta-analyses simply report “statistically significant” conclusions. However, statistics can be misleading. As Mark Twain said: “There are lies. There are damn lies. And then there are statistics”.

The problem is that the authors of most meta-analyses group studies together without considering the quality of studies included in their analysis. This creates a “Garbage In – Garbage Out” effect. If the quality of individual studies is low, the quality of the meta-analysis will also be low. Simply put, the conclusions from some published meta-analyses are not worth the paper they are written on.

The Cochrane Collaboration also reports statistically significant conclusions from their meta-analyses. However, they also carefully consider the quality of each individual study in their analysis. They look at possible sources of bias. They look at the design and size of the studies. Finally, they ask whether the conclusions are consistent from one study to the next. They clearly define the quality of evidence that backs up each of their conclusions as follows:

  • High-quality evidence. Further research is unlikely to change their conclusion. This is generally reserved for conclusions backed by multiple high-quality studies that have all come to the same conclusion. These are the recommendations that are most often adopted into medical practice.
  • Moderate-quality evidence. This conclusion is likely to be true, but further research could have an impact on it.
  • Low-quality evidence. Further research is needed and could alter the conclusion. They are not judging whether the conclusion is true or false. They are simply saying more research is needed to reach a definite conclusion.

Omega-3s Reduce Preterm Births

clinically provenHere are the conclusions that the Cochrane Collaboration said were supported by high-quality evidence:

  • Omega-3s reduce the risk of preterm births.
  • Omega-3s reduce the risk of low-birth-weight infants.

The authors concluded: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the risk of preterm birth…More studies comparing omega-3s and placebo are not needed at this point.”

In other words, they are saying this conclusion is definite. Omega-3 supplementation should become part of the standard of medical care for pregnant women.

However, they did say that further studies were needed “…to establish if, and how, outcomes vary by different types of omega-3s, timing [stage of pregnancy], doses [of omega-3s], or by characteristics of women.”

That’s because these variables were not analyzed in the Cochrane study. Their review and meta-analysis included clinical trials:

  • Of women at low, moderate, and high risk of poor pregnancy outcomes.
  • With DHA alone, with EPA alone, and with a mixture of both.
  • Omega-3 doses that were low (˂ 500 mg/day), moderate (500-1,000 mg/day), and high (> 1,000 mg/day).

Do Omega-3s Make For A Healthy Pregnancy?

What about the effect of omega-3s on other pregnancy outcomes?

The conclusions the Cochrane Collaboration said were supported by moderate quality evidence included reductions in:

  • Perinatal death.
  • Admissions to the neonatal intensive care unit.

There was not enough high or moderate quality data to determine the effect of omega-3s on other pregnancy outcomes such as postnatal depression. More research is still needed in those areas. However, if you do receive any of these benefits from omega-3 supplementation, you can just consider them as side benefits.

What Does This Report Mean For You?

pregnant women taking omega-31) The proven effect of omega-3 supplementation on preterm births is significant because preterm births increase the risk of:

  • Visual impairment.
  • Developmental Delay.
  • Learning difficulties.

2) The likely effect of omega-3s on admission to neonatal intensive care units is significant because those units are very expensive.

3) The Cochrane study did not determine whether omega-3 supplementation was equally important for women at low, moderate, and high likelihood of poor pregnancy outcomes.

  • Therefore, omega-3 supplementation should be considered for all pregnant women.

4) The Cochrane study did not determine whether omega-3 supplementation was equally important during the first, second, or third trimester.

  • Therefore, omega-3 supplementation should be considered by all women of childbearing age who might become pregnant and throughout pregnancy.

5) The Cochrane study did not determine whether DHA, EPA, or a mixture of the two was most effective.

  • Therefore, your omega-3 supplement should probably contain both DHA and EPA. A group of experts recently recommended  that adults consume at least 650 mg/day of omega-3s with ≥ 220 mg of that coming from DHA and ≥ 220 mg/day coming from EPA.
  • Since most pregnant women in this country consume around 89 mg/day of DHA + EPA, omega-3 supplementation is warranted.

The Bottom Line 

The effect of omega-3s on pregnancy outcomes have been confusing. Some studies conclude that omega-3s are important for a healthy pregnancy. Other studies suggest they are ineffective. What are you to believe?

Fortunately, a group called the Cochrane Collaboration recently conducted a comprehensive review of this topic. This is significant because Cochrane Reviews are internationally recognized as the highest standard in evidence-based health care. They influence the treatment protocols recommended by the medical community.

This Cochrane Review concluded that omega-3 supplementation during pregnancy:

  • Reduces preterm births and low birth weight infants.
  • Likely reduces perinatal death and admissions to the neonatal intensive care unit.

The authors of the review said: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the risk of preterm birth…More studies comparing omega-3s and placebo are not needed at this point.”

In other words, they are saying this conclusion is definite. Omega-3 supplementation should become part of the standard of medical care for pregnant women.

For more details on the 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.

Omega-3s And Congestive Heart Failure

We Have Been Asking The Wrong Questions 

Author: Dr. Stephen Chaney

Confusion Clinical StudiesToday’s Health Tip is a follow-up to the article I published last month on omega-3s and heart disease risk. In that article I pointed out the reasons why studies of the effect of omega-3s and heart disease risk have been so confusing.

One of the reasons is that many of the studies have been asking the wrong questions.

  • They were asking whether omega-3s reduced the risk of heart disease for everyone. Instead, they should have been asking who benefited from omega-3 supplementation.
  • They were asking whether omega-3s reduced the risk of all forms of heart disease combined. Instead, they should have been asking whether omega-3s reduced the risk of specific kinds of heart disease.

I also discussed a large clinical trial, the VITAL study, that was designed to answer those two questions.

The study I will describe today (L Djoussé et al, JACC Heart Failure, 10: 227-234, 2022) mined the data from the VITAL study to evaluate the effect of omega-3 supplementation on congestive heart failure, a form of heart disease that was not discussed in the VITAL study.

Everything You Need To Know About Congestive Heart Failure

Congestive Heart FailureCongestive heart failure is a killer. The term congestive heart failure simply means that your heart no longer pumps blood well. The initial symptoms are relatively non-specific and include things like.

  • Shortness of breath.
  • Fatigue and weakness.
  • Reduced ability to exercise.
  • Rapid or irregular heartbeat.
  • Persistent cough or wheezing.

However, as it progresses, the symptoms get much worse. Fluid builds up in your tissues.

  • Fluid buildup in your legs, ankles, and feet can make it difficult to walk.
  • Fluid buildup in your lungs makes it difficult to breathe. In advanced stages it can feel like you are drowning in a room full of air.

According to the CDC:

  • 4 million Americans have congestive heart failure (CHF).
    • It leads to ~380,000 deaths/year.
  • 83% of patients diagnosed with CHF will be hospitalized at least once.
    • 67% will be hospitalized two or more times.
  • CHF costs >$30 billion per year in health care costs and lost wages.

The risk of congestive heart failure is not spread evenly across the American population. Black Americans and Americans with type 2 diabetes are at increased risk.

According to the Framingham Heart Study:

  • Type 2 diabetes increases the risk of CHF 2-fold in men and 5-fold in women. The reasons are not entirely clear. However:
    • High blood sugar is thought to either damage cells in heart muscle, weakening it, or damage small blood vessels within the heart, making it more difficult for the heart to pump blood.
    • Some diabetes drugs that lower blood sugar also appear to increase the risk of congestive heart failure.

According to the CDC:

  • Black Americans are 2-fold more likely to develop CHF than White Americans. Again, the reasons are not clear. However:
    • Some experts feel it could be due to the higher incidence of untreated high blood pressure in Black Americans.

In summary:

  • Congestive heart failure is a serious disease. Its symptoms affect your quality of life, and it can lead to hospitalizations and death.
  • Black Americans and Americans with type 2 diabetes are at higher risk of developing congestive heart failure.

How Was The Study Done?

The VITAL study, from which these data were extracted, was a placebo-controlled clinical trial designed to measure the effects of 1,000 mg omega-3 supplementation on the risk of developing heart disease. It enrolled 25,871 Americans aged 55 years or older and followed them for an average of 5.3 years.

The participants enrolled in the VITAL study represented a cross-section of the American population. Most were at low risk of heart disease, but there were subsets of the study group who were at higher risk of heart disease. A strength of the VITAL study was that it was designed so the high-risk subgroups could be evaluated separately.

The current study utilized data from the VITAL study to look at the effect of omega-3 supplementation on hospitalizations due to congestive heart failure. It also evaluated the effect of type 2 diabetes and race on the risk of hospitalizations.

Omega-3s And Congestive Heart Failure

Omega-3s And Heart DiseaseWhen the investigators looked at the whole population, most of whom were at low-risk of congestive heart failure, they did not see any effect of omega-3 supplementation on the risk of hospitalizations due to congestive heart failure.

However, when they looked at high risk groups, the story was much different.

In patients with type-2 diabetes:

  • Omega-3 supplementation reduced the risk of the initial hospitalization for congestive heart failure by 31%
  • Omega-3 supplementation reduced the risk of multiple hospitalizations due to congestive heart failure by 47%.

The effect of omega-3 supplementation on hospitalizations was greatest for the Black participants in the study.

In the words of the authors, “Our data show beneficial effects of omega-3 fatty acid supplements on the incidence of heart failure hospitalizations in participants with type 2 diabetes but not in those without type 2 diabetes, and such benefit appeared to be stronger in Black participants with type 2 diabetes.”

We Are Asking The Wrong Questions

ScientistAs I said above, there is so much confusion about the effect of omega-3s on heart disease because we scientists have been asking the wrong questions:

  • We have been asking whether omega-3s reduce the risk of heart disease for everyone. Instead, we should have been asking who benefits from omega-3 supplementation.
  • We have been asking whether omega-3s reduced the risk of all forms of heart disease combined. Instead, we should have been asking whether omega-3s reduced the risk of specific kinds of heart disease.

In my “Health Tip” last month I discussed a large clinical study, the VITAL study, that was specifically designed to answer the right questions. Like so many other studies it found that omega-3 supplementation did not significantly reduce the risk of all kinds of heart disease for everyone.

However, what it did find was more important than what it did not find:

  • When they looked at the effect of omega-3s on heart disease risk in high-risk groups, they found that major cardiovascular events were reduced by:
    • 26% in African Americans.
    • 26% in patients with type 2 diabetes.
    • 17% in patients with a family history of heart disease.
    • 19% in patients with two or more risk factors of heart disease.
  • When they looked at the effect of omega-3s on heart disease risk in people with low omega-3 intake, they found that omega-3 supplementation reduced major cardiovascular events by:
    • 19% in patients with low fish intake.
  • When they looked at the effect of omega-3s on the risk of different forms of heart disease, they found that omega-3 supplementation reduced:
    • Heart attacks by 28% in the general population and by 70% for African Americans.
    • Deaths from heart attacks by 50%.
    • Deaths from coronary heart disease (primarily heart attacks and ischemic strokes (strokes caused by blood clots)) by 24%.

In other words, when they asked the wrong questions, they got the wrong answer. If they had just looked at the effect of omega-3 supplementation on all forms of heart disease for everyone (like most other omega-3 studies), they would have concluded that omega-3s are worthless.

However, when they asked the right questions, they found that omega-3s were very beneficial for high-risk populations and for certain types of heart disease.

The current study utilized the same data to analyze the effect of omega-3 supplementation on hospitalizations due to congestive heart failure. And the results were similar.

If they had asked the wrong question, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for everyone?”, they would have concluded that omega-3 supplementation was worthless.

However, instead they asked, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for certain high-risk groups” and were able to show that omega-3 supplementation significantly reduced congestive heart failure hospitalizations for people with type 2 diabetes and for Blacks.

We need to change the paradigm for clinical studies of supplements. The old paradigm asks the wrong questions. If we really want to know the role of supplementation for our health, we need to start asking the right questions.

The Bottom Line

There is perhaps nothing more confusing to the average person than the “truth” about omega-3 supplementation and heart disease risk. Much of the confusion is because we have been asking the wrong questions:

  • We have been asking whether omega-3 supplementation reduces the risk of heart disease for everyone. Instead, we should have been asking who benefits from omega-3 supplementation.
  • We have been asking whether omega-3 supplementation reduces the risk of all forms of heart disease combined. Instead, we should have been asking whether omega-3 supplementation reduces the risk of specific kinds of heart disease.

A recent study on the effect of omega-3 supplementation on hospitalizations due to heart disease is a perfect example.

If they had asked the wrong question, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for everyone?”, they would have concluded that omega-3 supplementation was worthless.

However, instead they asked, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for certain high-risk groups” and were able to show that omega-3 supplementation significantly reduced congestive heart failure hospitalizations for people with type 2 diabetes and for Blacks.

We need to change the paradigm for clinical studies of supplements. The old paradigm asks the wrong questions. If we really want to know the role of supplementation for our health, we need to start asking the right questions.

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.

Is Low Omega-3 Intake As Bad For You As Smoking?

What Is The Omega-3 Index And Why Is It Important? 

Author: Dr. Stephen Chaney

deadWe already know that smoking is one of the worst things we can do to our bodies. It dramatically increases our risk of cancer, heart disease, diabetes, and lung diseases, including chronic obstructive pulmonary disease (COPD).

It also leads to premature death. People who smoke regularly die 5 years earlier than those who don’t.

That is the bad news. The good news is that smoking is what is called a “modifiable risk factor”. Simply put, that means it is a risk factor we are in control of. The message has been clear for years.

  • If you don’t smoke, keep it that way.
  • If you do smoke, stop. If you are a smoker, quitting isn’t easy, but it is worth it. The damage caused by smoking can largely be reversed if you stay off cigarettes long enough.

Obesity and diabetes are also modifiable risk factors that have a huge effect on the risk of both heart disease and premature death. People with diabetes die 4 years earlier than those without diabetes. But obesity and diabetes are harder for most people to reverse than smoking.

Diet is another modifiable risk factor, but, in general, its effect on the risk of heart disease and premature death is not as great as smoking and diabetes. But what if there were one component of diet that had huge effect on both heart disease and premature death?

The long chain omega-3 fatty acids (EPA & DHA) might just fill that bill. We already know they significantly reduce the risk of heart disease (see below), but could they also help us live longer? This study (MI McBurney et al, American Journal of Clinical Nutrition, published online June 16, 2021) was designed to answer that question.

Metabolism 101: What Is The Omega-3 Index And Why Is It Important?

professor owlClinical studies on the benefits of omega-3s have been plagued by the question of how to best measure the omega-3 status of the participants.

  • You can ask the participants to fill out a dietary survey and calculate how many omega-3-rich foods they are eating, but:
    • Dietary recall is notoriously inaccurate. People don’t remember everything they ate and have a hard time estimating portion sizes.
  • You can measure omega-3 fatty acids in the blood, but:
    • Blood levels are transient. Omega-3 fatty acids enter the bloodstream from the intestine and then disappear from blood as they are taken up by the cells.
    • Different forms of omega-3s (esters versus acetate, for example) are absorbed from the intestine and taken up by cells at different rates.
  • You can measure the omega-3 content of cellular membranes. This is the best assay for omega-3 status because:
    • The long chain omega-3 fatty acids (EPA and DHA) that have the biggest effect on heart disease risk accumulate in our cell membranes.
    • Omega-3 fatty acids are essential (our bodies can’t make them). That means the omega-3 content of our cell membranes reflect the omega-3 content of our diet. This is one of the cases where the saying, “We are what we eat”, is literally true.
    • The omega-3 content of our cell membranes is relatively stable. It reflects the omega-3 content of our diet over the last few months.
  • In theory, you could measure the omega-3 content of cell membranes from any tissues in the body, but red blood cells can easily be obtained by a simple blood draw, so they are the tissue of choice.

A group lead by Dr. William H Harris standardized this measurement by creating something called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA in red blood cell membranes.

It turns out that the Omega-3 Index is an excellent indicator of heart disease risk.

  • An Omega-3 Index of less than 4% is associated with a high risk of heart disease.
  • An Omega-3 Index of more than 8% is associated with a low risk of heart disease.

But could a low Omega-3 Index also be associated with an increased risk of premature death? This is what the current study was designed to find out.

How Was This Study Done?

Clinical StudyThe data for this study were obtained from the ongoing Framingham Offspring Heart Study.

To put this statement into perspective, the original Framingham Heart Study began in 1948 in Framingham Massachusetts with the goal of identifying the factors that contributed to heart disease. It was one of the first major studies to identify the role of saturated fats, elevated blood cholesterol, and elevated blood triglycerides on heart disease risk.

The study is continuing today with the second and third generation descendants of the original study participants. It has also been broadened to include other diseases and additional risk factors, such as the Omega-3 Index.

This study selected 2240 participants from the Framingham Offspring study who had no heart disease and also had Omega-3 Index measurements at the beginning of the study. The study then followed them for 11 years. The goal of the study was to compare the Omega-3 Index with the two most potent risk factors for heart disease (smoking and diabetes) in predicting the risk of premature death.

The characteristics of the participants at the beginning of the 11-year study were:

  • 43% male, 57% female.
  • Average age = 65.
  • 3% were smokers.
  • 8% were diabetic.
  • Average Omega-3-Index = 5.8%. This is slightly higher than the American average of ~5%.

Is Low Omega-3-Intake As Bad For You As Smoking?

omega-3 supplements and heart healthThe participants in the study were divided into 5 quintiles based on their Omega-3 Index.

  • The 20% of the group in the lowest quintile had an Omega-3 Index of <4.2%.
  • The 20% of the group in the highest quintile had an Omega-3 Index of >6.8%.

First, the scientists running the study did a direct comparison of the top three risk factors on the risk of premature death. Here is what they found.

  • The group with the lowest average Omega-3 Index died 4.74 years earlier than the group with the highest average Omega-3 Index.
  • Smokers died 4.73 years earlier than non-smokers.
  • People with diabetes died 3.90 years earlier than people without diabetes.

That means low omega-3 intake was just as bad for the participants in this study as smoking. Even the authors of the study were surprised by this result. They had expected omega-3 fatty acids to be beneficial, but they had not expected them to be as beneficial as not smoking.

Because omega-3 fatty acid intake and smoking were the two most potent risk factors for premature death, the authors looked at the interaction between the two. They found that the predicted 11-year survival was:

  • 85% for non-smokers with high omega-3 intake.
  • 71% for either…
    • Smokers with high omega-3 intake, or…
    • Non-smokers with low omega-3 intake.
  • Only 47% for smokers with low omega-3 intake.

Simply put, this study predicts if you were a 65-year-old smoker with low omega-3 intake, you could almost double your chances of surviving another 11 years by giving up smoking and increasing your omega-3 intake.

In the words of the authors, “Smoking and omega-3 intake seem to be the most easily modified risk factors [for premature death]…Dietary choices that change the Omega-3 index may prolong life.”

The Bottom Line

We know that smoking is deadly, but could low intake of omega-3 fatty acids be just as deadly?

A recent study compared omega-3 intake with the two most potent risk factors (smoking and diabetes) in predicting the risk of premature death. Here is what it found.

  • The group with the lowest average omega-3 intake died 4.74 years earlier than the group with the highest average omega-3 intake.
  • Smokers died 4.73 years earlier than non-smokers.
  • People with diabetes died 3.90 years earlier than people without diabetes.

That means high omega-3 intake was just as beneficial for the participants in this study as not smoking. Even the authors of the study were surprised by this result. They had expected omega-3 fatty acids to be beneficial, but they had not expected them to be as beneficial as not smoking.

Because omega-3 fatty acid intake and smoking were the two most potent risk factors for premature death, the authors looked at the interaction between the two. They found that the predicted 11-year survival was:

  • 85% for non-smokers with high omega-3 intake.
  • 71% for either…
    • Smokers with high omega-3 intake, or…
    • Non-smokers with low omega-3 intake.
  • Only 47% for smokers with low omega-3 intake.

Simply put, this study predicts if you were a 65-year-old smoker with low omega-3 intake, you could almost double your chances of surviving another 11 years by giving up smoking and increasing your omega-3 intake.

In the words of the authors, “Smoking and omega-3 intake seem to be the most easily modified risk factors [for premature death]…Dietary choices that change the Omega-3 index may prolong life.”

For more details about this study, 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.

What Is An Anti-Inflammatory Diet?

Can Diet Douse The Flames?

Author: Dr. Stephen Chaney

InflammationIf you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It is something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. How good is the evidence that certain foods influence inflammation, and what does an anti-inflammatory diet look like?

The Science Behind Anti-Inflammatory Diets

ScientistLet me start by saying that the science behind anti-inflammatory diets is nowhere near as strong as it is for the effect of primarily plant-based diets on heart disease and diabetes. The studies on anti-inflammatory diets are mostly small, short duration studies. However, the biggest problem is that there is no standard way of measuring inflammation.

There are multiple markers of inflammation, and they do not change together. That means that in every study some markers of inflammation are altered, while others are not. There is no consistent pattern from one study to another.

In spite of these methodological difficulties, the studies generally point in the same direction. Let’s start with the strongest evidence and work our way down to the weakest evidence. 

Omega-3 fats are anti-inflammatory (I. Reinders et al, European Journal of Clinical Nutrition, 66: 736-741, 2011). The evidence is strongest for the long chain omega-3s found in fish and fish oil, but the shorter chain omega-3s found in foods like walnuts, flaxseeds, chia seeds and flaxseed oil, soybean oil, and canola oil also appear to be anti-inflammatory. 

Inflammation is directly correlated with glycemic index (L. Qi and F.B. Lu, Current Opinion in Lipidology, 18: 3-8, 2007). This has a couple of important implications.

The most straightforward is that refined carbohydrates and sugars (sodas, pastries, and desserts), which have a high glycemic index, increase inflammation. In contrast, complex carbohydrates (whole grains, most fruits and vegetables) decrease inflammation. No surprise there. The second implication is that it is the glycemic index, not the sugar, that is driving the inflammatory response.

That means we need to look more closely at foods than at sugars. Sodas, pastries and desserts are likely to cause inflammation, but sugar-containing foods with a low glycemic index are unlikely to be inflammatory. 

Fruits and vegetables are anti-inflammatory. This has been shown in multiple studies. At this point most of the research is centered on identifying the nutrients and phytonutrients from fruits and vegetables that are responsible for the reduction in inflammation. I suspect the investigators are hoping to design an anti-inflammatory supplement and make lots of money. I will stick with the fresh fruits and vegetables. 

Saturated fats are inflammatory. At face value, the data on saturated fats appear to be contradictory. Some Fatty Foodsstudies say that saturated fats increase inflammation, while others say they do not. However, similar to my earlier discussion on saturated fats and heart disease), the outcome of the study depends on what the saturated fats are replaced with.

When saturated fats are replaced with refined carbohydrates, sugar and highly processed foods (the standard American low-fat diet), inflammation doesn’t change. This doesn’t mean that a diet high in saturated fat is healthy. It just means that both diets are bad for you. Both are inflammatory.

However, when saturated fat is replaced with omega-3 polyunsaturated fats (J.A. Paniagua et al, Atherosclerosis, 218: 443-450, 2011) or monounsaturated fats (B. Vessby et al, Diabetologia, 44: 312-319, 2001), markers of inflammation decrease. Clearly, saturated fats are not the best fat choice if you wish to keep inflammation in check.

I would be remiss if I did not address the claims by the low-carb diet proponents that saturated fats do not increase inflammation in the context of a low-carb diet. I want to remind you of two things we have discussed previously:

  • The comparisons in those studies are generally with people consuming a diet high in simple carbohydrates and sugars.
  • These studies have mostly been done in the short-term when the participants are losing weight on the low-carb diets. Weight loss decreases inflammation, so the reduction in inflammation on the low-carb diet could be coming from the weight loss.

The one study (M. Miller et al, Journal of the American Dietetic Association, 109: 713-717, 2009) I have found that compares a low-carb diet (the Atkins diet) with a good diet (the Ornish diet, which is a low-fat, lacto-ovo vegetarian diet) during weight maintenance found that the meat based, low-carb Atkins diet caused greater inflammation than the healthy low-fat Ornish diet.

Red meat is probably pro-inflammatory. Most, but not all, studies suggest that red meat consumption is associated with increased inflammation. If it is pro-inflammatory, the inflammation is most likely associated with its saturated fat, its heme iron content, or the advanced glycation end products formed during cooking.

What Is An Anti-Inflammatory Diet?

Colorful fruits and vegetablesAnti-inflammatory diets have become so mainstream that they now appear on many reputable health organization websites such as Harvard Health, WebMD, the Mayo Clinic, and the Cleveland Clinic. Each have slightly different features, but there is a tremendous amount of agreement. 

Foods an anti-inflammatory diet includes: In a nutshell, an anti-inflammatory diet includes fruits and vegetables, whole grains, plant-based proteins (like beans and nuts), fatty fish, and fresh herbs and spices. Specifically, your diet should emphasize:

  • Colorful fruits and vegetables. Not only do they help fight inflammation, but they are a great source of antioxidants and other nutrients important for your health.
  • Whole grains. They have a low glycemic index. They are also a good source of fiber, and fiber helps flush inflammatory toxins out of the body.
  • Beans and other legumes. They should be your primary source of protein. They are high in fiber and contain antioxidants and other anti-inflammatory nutrients.
  • Nuts, olive oil, and avocados. They are good sources of healthy monounsaturated fats, which fight inflammation.
  • Fatty fish. Salmon, tuna, and sardines are all great sources of long chain omega-3 fatty acids, which are fish and fish oilincorporated into our cell membranes. Those long chain omega-3s in cell membranes are, in turn, used to create compounds that are powerful inflammation fighters.

Walnuts, flaxseeds, and chia seeds are good sources of short chain omega-3s. The efficiency of their conversion to long chain omega-3s that can be incorporated into cell membranes is only around 2-5%. If they fight inflammation, it is probably because they replace some of the saturated fats and omega-6 fats you might otherwise be eating.

  • Herbs and spices. They add antioxidants and other phytonutrients that fight inflammation.

Foods an anti-inflammatory diet excludes: In a nutshell, an anti-inflammatory diet should exclude highly processed, overly greasy, or super sweet foods, especially sodas and other sweet drinks. Specifically, your diet should exclude:

  • Refined carbohydrates, sodas and sugary foods. They have a high glycemic index, which is associated with inflammation. They can also lead to weight gain and high blood sugar, both of which cause inflammation.
  • Foods high in saturated fats. This includes fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats. This includes margarine, coffee creamers, and any processed food containing partly hydrogenated vegetable oils. Trans fats are very pro-inflammatory.
  • French fries, fried chicken, and other fried foods. They used to be fried in saturated fat and/or trans fat. Nowadays, they are generally fried in omega-6 vegetable oils. A little omega-6 in the diet is OK, but Americans get too much omega-6 fatty acids in their diet. Most studies show that a high ratio of omega-6 to omega-3 fatty acids is pro-inflammatory.
  • Foods you are allergic or sensitive to. Eating any food that you are sensitive to can cause inflammation. This comes up most often with respect to gluten and dairy because so many people are sensitive to one or both. However, if you are not sensitive to them, there is no reason to exclude whole grain gluten-containing foods or low-fat dairy foods from your diet.

Can Diet Douse The Flames?

FlamesIn case you didn’t notice, the recommendations for an anti-inflammatory diet closely match the other healthy diets I have discussed previously. It should come as no surprise then that both the Mediterranean (L. Gallard, Nutrition in Clinical Practice, 25: 634-640, 2010; L. Schwingshackl and G. Hoffmann, Nutrition Metabolism and Cardiovascular Diseases, 24: 929-939, 2014) and DASH (D.E. King et al, Archives of Internal Medicine, 167: 502-506, 2007) diets are anti-inflammatory.

Vegan and vegetarian diets also appear to be anti-inflammatory as well. The anti-inflammatory nature of these diets undoubtedly contributes to their association with a lower risk of heart disease, diabetes, and cancer.

As for the low-carb diets, the jury is out. There are no long-term studies to support the claims of low-carb proponents that their diets reduce inflammation. The few long-term studies that are available suggest that low-carb diets are only likely to be anti-inflammatory if vegetable proteins and oils replace the animal proteins and fats that are currently recommended.

What does this mean for you if you have severe arthritis or other inflammatory diseases? An anti-inflammatory diet is unlikely to “cure” your symptoms by itself. However, it should definitely be a companion to everything else you are doing to reduce inflammation.

The Bottom Line 

If you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It’s something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. In this article I review the evidence that certain foods influence inflammation and describe what an anti-inflammatory diet looks like.

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.

Update On Omega-3 Supplementation And Heart Disease

How Much Omega-3s Do You Need?

Pendulum
Pendulum

In previous issues of “Health Tips From The Professor” I have described the medical consensus about omega-3 supplementation and heart disease as resembling a pendulum.

A few positive studies are published, and the pendulum swings in the positive direction. The medical consensus becomes, “Omega-3s may reduce heart disease risk.”

Then a few negative studies are published, and the pendulum swings in the other direction. The consensus becomes that omega-3 supplements are worthless. One review a few years ago went so far as to say that fish oil supplements were the modern-day version of snake oil.

Meta-analyses combine the data from multiple clinical studies to increase statistic power and minimize the effect of clinical studies that are outliers. They are supposed to provide clear answers to medical questions like the effect of omega-3 supplements on heart disease.

However, the meta-analyses published to date have also reached conflicting conclusions about the effectiveness of omega-3 supplementation. No wonder you [and the medical community] are confused!

In 2018 three large, well-designed, clinical studies looking at the effect of omega-3 supplementation on heart disease risk were published. They reached different conclusions. However, they covered a much wider range of omega-3 doses than previous studies. And the studies with the highest doses of omega-3s showed the most positive effect of omega-3 supplementation on the reduction of heart disease risk.

That lead a group of doctors and scientists from the United States and Finland to postulate that many previous studies had failed to find an effect of omega-3 supplements on heart disease risk because the dose of omega-3s they used was too low.

These scientists designed a very large meta-analysis (AA Bernasconi et al, Mayo Clinic Proceedings, doi.org/10.1016/j.mayocp.2020.08.034) to test their hypothesis. In short, their study was designed to:

  • Determine whether supplementation with the omega-3 fatty acids EPA and DHA resulted in reduced heart disease risk.
  • Quantify the relationship between the dose of EPA + DHA and the risk of heart disease outcomes.

How Was The Study Done?

Clinical StudyThis study was a meta-analysis of 40 randomized control clinical studies on the effect omega-3 supplementation on heart disease outcomes. Specifically:

  • It included all high-quality clinical studies of omega-3 supplementation published before August 2019.
  • It included a total of 135,267 participants.
  • It included participants at both low and high risk of developing heart disease.
  • It included studies of supplementation with EPA alone and with EPA + DHA.
  • It included omega-3 doses ranging from 400 mg/day to 5,500 mg/day.
  • It excluded dietary studies because:
    • It is difficult to measure the dosage of omega-3s that participants are consuming in dietary studies.
    • It is difficult to assure their compliance with dietary advice.
    • There is variation in the omega-3 content of various foods.
    • Participants in these studies are often advised to make other changes in diet. It then becomes difficult to know whether any benefits observed were from changes in omega-3s or from changes in other components of the diet.

Update On Omega-3 Supplementation And Heart Disease

omega-3 supplements and heart healthHere are the results of the meta-analysis. Supplementation with EPA or EPA + DHA reduced:

  • Coronary Heart disease (defined as diseases caused by atherosclerosis, such as angina, heart attack, and heart failure) by 10%.
  • Heart Attacks by 13%.
  • Coronary Heart disease deaths by 9%.
  • Heart attack deaths by 35%.

Because of the large number of participants in this meta-analysis, they were able to reach some other important conclusions:

  • Despite the claims you may have heard about a new drug consisting of highly purified EPA, this study found no evidence that EPA supplementation was superior to EPA + DHA supplementation.
  • Even though heart medications provide some of the same benefits as omega-3s, this study concluded that omega-3 supplementation reduced the risk of heart disease even for patients on multiple heart medications.
  • This study also concluded that omega-3 supplementation was likely to be effective for people at both low and high risk of heart disease. This means that omega-3 supplementation is likely to be beneficial for preventing heart disease.

The authors concluded: “The current study provides strong evidence that EPA + DHA supplementation is an effective strategy for the prevention of certain coronary heart disease outcomes…Considering the relatively low costs and side effect profiles of omega-3 supplementation and the low drug-drug interactions with other standard therapies…clinicians and patients should consider the potential benefits of omega-3 (EPA/DHA) supplementation…”

What Does This Study Mean For You?

Heart AttackThe most significant conclusions from this study are the reduction in heart attacks and heart attack deaths. That is because:

  • Approximately 1.5 million Americans suffer a heart attack each year. For those who survive their quality of life may be permanently altered.
    • A 13% reduction in heart attacks means that something as simple as EPA + DHA supplementation might prevent as many as 195,000 heart attacks a year.
  • Approximately 100,000 Americans will die from a heart attack each you.
    • A 35% reduction in heart attack deaths means that EPA + DHA supplementation might prevent as many as 35,000 deaths from heart attacks each year.
  • For many Americans sudden death from a heart attack is the first indication that they have heart disease.
    • As Benjamin Franklin said, “An ounce of prevention is worth a pound of cure”. That is why EPA + DHA supplementation makes sense for most people.

I can’t say that this study will be the final word on omega-3 supplementation and heart disease risk. However, several recent studies have supported the benefit of omega-3 supplementation at reducing heart disease risk. The pendulum has clearly swung in the direction of omega-3s being beneficial for heart health.

Of course, omega-3 supplementation is not a magic “Get Out of Jail Free” card. You can’t expect it to overcome the effects of a bad diet and lack of exercise with omega-3 supplementation alone. You need a holistic approach.

The American Heart Association recommends:

Doctor With Patient

  • If you smoke, stop.
  • Choose good nutrition.
    • Choose a diet that emphasizes vegetables, fruits, whole grains, low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils, and nuts.
    • Choose a diet that limits sweets, sugar-sweetened beverages, and red meats.
  • Reduce high blood cholesterol and triglycerides.
  • Reduce your intake of saturated fat, trans fat and cholesterol and get moving.
  • Lower High Blood Pressure.
  • Be physically active every day.
    • Aim for at least 150 minutes per week of moderate-intensity physical activity per week.
  • Aim for a healthy weight.
  • Manage diabetes.
  • Reduce stress.
  • Limit alcohol.
  • Have a regular physical checkup.

Add in omega-3 supplementation to these recommendations and you have a winning combination.

How Much Omega-3s Do You Need?

Question MarkAs I mentioned at the beginning of this article the omega-3 dosages used in the studies included in this meta-analysis ranged from 400 mg/day to 5,500 mg/day. More importantly, there were enough participants in these studies to obtain a fairly accurate estimate of dose response. This allow the authors to answer the question, “How much omega-3s do I need?”The study found that:

  • The protective effect of omega-3s for heart attack deaths and coronary heart disease deaths plateaued with dosages of EPA + DHA that exceeded 800 – 1200 mg/day.
  • The dose response of the protective effect of omega-3s for non-fatal heart attacks was linear over a wider range of dosages, with every increase 1,000 mg/day of EPA + DHA decreasing the risk of heart attack by 9%.

Based on the totality of their data, the authors concluded, “…clinicians and patients should consider the potential benefits of omega-3 supplementation, especially using 1,000 to 2,000 mg/day dosages, which are rarely obtained in most Westernized diets, even those including routine fish consumption.”

The Bottom Line

A recent meta-analysis combined the data from 40 clinical studies with over 135,000 participants looking at the effect of omega-3 supplementation on various types of heart disease. The study found that supplementation with EPA or EPA + DHA reduced:

  • Coronary Heart disease (defined as diseases caused by atherosclerosis, such as angina, heart attack, and heart failure) by 10%.
  • Heart Attacks by 13%.
  • Coronary Heart disease deaths by 9%.
  • Heart attack deaths by 35%.

Because of the large number of participants in this meta-analysis, they were able to reach some other important conclusions:

  • This study found no evidence that EPA supplementation was superior to EPA + DHA supplementation.
  • This study concluded that omega-3 supplementation reduced the risk of heart disease even for patients on multiple heart medications.
  • This study also concluded that omega-3 supplementation was likely to be effective for people at both low and high risk of heart disease. This means that omega-3 supplementation is likely to be beneficial for preventing heart disease.
  • The optimal dose of EPA + DHA appeared to be 1,000 – 2,000 mg/day.

The authors of the study concluded: “The current study provides strong evidence that EPA + DHA supplementation is an effective strategy for the prevention of certain coronary heart disease outcomes…Considering the relatively low costs and side effect profiles of omega-3 supplementation and the low drug-drug interactions with other standard therapies…clinicians and patients should consider the potential benefits of omega-3 (EPA/DHA) supplementation, especially using 1,000 to 2,000 mg/day dosages, which are rarely obtained in most Westernized diets, even those including routine fish consumption.”

For more details, including a more detailed discussion of what this study 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.

Do Omega-3 Supplements Reduce ADHD Symptoms?

Will The Omega-3 Controversy Continue?

adhd symptoms childrenThe prevalence of ADHD has increased dramatically in the last couple of decades. One study reported that the percentage of children diagnosed with ADHD has increased by 42% between 2003 and 2011. Another study reported an increase of 67% between 1997 and 2015. Currently, 10-12% of American schoolchildren are diagnosed with ADHD. That amounts to around 6 million children with ADHD, at a cost to taxpayers of over $45 billion.

An estimated 65% of children with ADHD are taking medications to control their symptoms. Unfortunately, those medications don’t work for 20-40% of patients with ADHD. Even worse, ADHD medications come with serious side effects like loss of appetite and delayed growth, sleep disorders, nausea & stomach pains, headaches, moodiness and irritability.

Even more worrisome is that many children say they “just don’t feel right” while they are on the drugs. Finally, there is the unintended message we are sending our children that drugs are the solution to their problems.

It is no wonder that millions of parents are looking for more natural solutions for their child’s ADHD. One of the most popular natural approaches is supplementation with omega-3s. But do omega-3 supplements work, or is this just another myth created by supplement companies to lighten your wallet?

The scientific evidence is conflicting. Some clinical studies support the efficacy of omega-3 supplements for reducing ADHD symptoms. Other studies claim they have no benefit.

In today’s issue of “Health Tips From The Professor”, I review a recent meta-analysis (JP-C Chang et al, Neuropsychopharmacology, 43: 534-545, 2018) that attempts to provide a definitive answer to this question.

How Was The Study Done?

Clinical StudyThis study was designed to answer three questions:

1)    Does omega-3 supplementation reduce ADHD symptoms?

2)    Does omega-3 supplementation improve cognitive skills in children with ADHD?

3)    Is there an association between omega-3 status and ADHD?

Previous meta-analyses on these topics had design flaws such as:

·       Including both children and adult subjects.

·       Including subjects with diagnosis other than ADHD.

·       Including trials that supplemented with vitamins and other nutrients in addition to omega-3s.

The authors of this study tried to avoid these limitations by using the following criteria for the studies that were included in their meta-analysis.

1)    The studies were randomized, double-blind, placebo-controlled trials of omega-3 supplementation with DHA and EPA alone or in combination.

2)    The participants were school-aged children (4-12 years) and adolescents (13-17 years) who had a diagnosis of ADHD.

3)    The study measured the effect of omega-3 supplementation on clinical symptoms of ADHD or measures of cognitive performance (omission errors, commission errors, forward memory, backward memory, and information processing).

4)    The studies were large enough to measure statistically significant differences.

5)    The studies were published in peer-reviewed journals.

With these criteria there were:

·       Seven studies with 534 children looking at the effect of omega-3 supplementation on ADHD symptoms.

·       Three studies with 214 children looking at the effect of omega-3 supplementation on cognitive performance.

·       Twenty studies with 1276 children looking at the association between omega-3 status and ADHD.

Do Omega-3 Supplements Reduce ADHD Symptoms?

adhd symptoms omega-3sThe results of this meta-analysis were as follows:

1)    Omega-3 supplementation significantly reduced ADHD symptoms reported by parents.

2)    Omega-3 supplementation significantly improved cognitive measures associated with attention span (omission and commission errors). [Note: Omission errors consist of leaving important information out of an answer. Commission errors consist of including incorrect information in an answer.]

·       Omega-3 supplementation did not improve cognitive measures associated with memory and information processing. This has also been reported in most previous studies.

·       The best way to think of this is that children with ADHD are fully capable of learning their schoolwork. However, they may have trouble demonstrating what they have learned on exams because of omission and commission errors.

·       In this context, omega-3 supplementation may help them perform better on exams and reduce test-taking anxiety.

3)    For hyperactivity, only studies with EPA dosages of 500 mg per day or greater showed a significant reduction in symptoms.

4)    Children diagnosed with ADHD have lower levels of DHA, EPA, and total omega-3s.

The authors concluded: “In summary, there is evidence that omega-3 supplementation … improves clinical symptoms and cognitive performances in children and adolescents with ADHD, and that these youth have a deficiency in omega-3 levels. Our findings provide further support to the rationale for using omega-3s as a treatment option for ADHD.”

They also said: “Our paper shows that EPA supplementation dosage >500 mg should be considered when treating youth with ADHD, especially those with predominantly hyperactivity/impulsivity presentation.”

Will The Omega-3 Controversy Continue?

ArgumentThis is an excellent study, but it is unlikely to be the final word on this subject. That is because there is a fundamental flaw in all previous studies on this important subject, including the ones included in this meta-analysis.

In the words of the authors: “In terms of ‘personalized medicine’, it is tempting to speculate that a subpopulation of youth with ADHD and low levels of omega-3s may respond better to omega-3 supplementation, but there are no studies to date attempting this approach.”

Until studies of omega-3 supplementation and ADHD symptoms include measures of omega-3 status before and after supplementation, those studies are likely to continue giving conflicting results. That is because:

·       If most of the children in the study have low omega-3 status, we are likely to see a positive effect of omega-3 supplementation on ADHD symptoms.

·       If most of the children in the study have high omega-3 status, we are likely to see a negative effect of omega-3 supplementation on ADHD symptoms.

What Does This Study Mean For You?

confusionWhile this study is unlikely to end the omega-3 controversy, it is a very well-designed study that combines the results of multiple double-blind, placebo-controlled clinical trials. In short, it is a very strong study.

Omega-3s have no side effects and multiple health benefits. If your child suffers from ADHD, omega-3 supplementation is worth a try.

However, we need to keep omega-3 supplementation in perspective:

·       Not every child with ADHD will respond to omega-3 supplementation.

·       Omega-3s alone are likely to reduce, but not eliminate, the symptoms.

·       There are other natural approaches that should be considered.

You will find details on omega-3s and other natural approaches for reducing ADHD symptoms in an earlier issue of “Health Tips From The Professor”.

The Bottom Line

A recent meta-analysis looked at the effect of omega-3 supplementatation on ADHD symptoms. Here is a brief summary of the data:

1)    Omega-3 supplementation significantly reduced ADHD symptoms reported by parents.

2)    Omega-3 supplementation significantly improved cognitive measures associated with attention span (omission and commission errors). [Note: Omission errors consist of leaving important information out of an answer. Commission errors consist of including incorrect information in an answer.]

·       Omega-3 supplementation did not improve cognitive measures associated with memory and information processing. This has also been reported in most previous studies.

·       The best way to think of this is that children with ADHD are fully capable of learning their schoolwork. However, they may have trouble demonstrating what they have learned on exams because of omission and commission errors.

·       In this context, omega-3 supplementation may help them perform better on exams and reduce test-taking anxiety.

3)    For hyperactivity, only studies with EPA dosages of 500 mg per day or greater showed a significant reduction in symptoms.

4)    Children diagnosed with ADHD have lower levels of DHA, EPA, and total omega-3s.

The authors concluded: “In summary, there is evidence that omega-3 supplementation … improves clinical symptoms and cognitive performances in children and adolescents with ADHD, and that these youth have a deficiency in omega-3 levels. Our findings provide further support to the rationale for using omega-3s as a treatment option for ADHD.”

They also said: “Our paper shows that EPA supplementation dosage >500 mg should be considered when treating youth with ADHD, especially those with predominantly hyperactivity/impulsivity presentation.”

For more details on the study and a perspective on omega-3 supplementation compared to other natural approaches for reducing ADHD symptoms, 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.

Can Fish Oil Make Children Smarter?

When Do Omega-3 Supplements Make Sense?

Author: Dr. Stephen Chaney

Confused ChildWe know that the omega-3 fatty acids found in fish oil are critically important for brain development. But will they really help our kids learn better? Some studies suggest that they do, while other studies have come up empty. Why is this? More importantly, what does it mean for your children? Will fish oil supplements help or not?

I’ve selected today’s study (Portillo-Reyes et al, Research in Developmental Disabilities, 35: 861-870, 2014) because it sheds some light on those important questions.

Can Fish Oil Make Children Smarter?

This study looked at the effect of supplementation for 3 months with 360 mg of EPA + DHA on cognitive function of malnourished Mexican children, ages 8-12 years old. The children came from poor neighborhoods where foods rich in omega-3 fatty acids were seldom available. Low intake of omega-3 fatty acids was confirmed by a food frequency survey.

Cognition was assessed based on a battery of 16 standardized cognition tests at the beginning of the study and again 3 months later.

The results were fairly clear cut. The children receiving the fish oil supplements showed significant gains in mental processing speed, visual-motor coordination, perceptual integration, attention span and executive function compared to children receiving a placebo. In case you were wondering, the first three most strongly affect a child’s ability to learn and last two affect their tendency to display ADHD symptoms.

What Is the Significance of This Study?

There are a lot of things not to like about the study:

  • It was a small study (59 children total)
  • Blood levels of omega-3 fatty acids were not determined.
  • It was a short term study (12 months would have been better).
  • Measuring the ability to learn is difficult. Experts in the field differ about which cognitive tests are best. I’m not taking a position on the adequacy of the tests they were using because that is not my area of expertise.
  • Because it was done in a poor region of Mexico, one could argue that its applicability to children in this country is uncertain.

 

So why even mention this study? That’s because it illustrates an important principle – one that is often ignored in the design and interpretation of clinical studies.

Simply put, the principle is that not everyone will benefit equally from supplementation. It is the malnourished and the sick who will benefit most. When you focus your clinical studies on those groups you are most likely to observe a benefit of supplementation. When you focus your study on well nourished, healthy individuals it will be much more difficult to observe any benefit. And if you perform a meta-analysis of all studies, without evaluating the studies on the basis of need – nutrition status and health status – benefits will also be much more difficult to demonstrate.

This study is just one example of that principle. In an earlier “Health Tips From the Professor” (Can DHA Help Johnny Read?) I reported on a study looking at the effect of DHA supplementation on reading ability of English schoolchildren. In that study, it was the children who were most deficient in DHA and started with the lowest reading skills who benefitted most from DHA supplementation.

What does all of this mean to you?

  • If you are a parent, you may be asking if a study done with Mexican children eating poor diets has any relevance for your kids. In today’s world of pop tarts and pizza it just might. Most children don’t order sardines on their pizza. As a consequence, many American children don’t get enough omega-3 fatty acids in their diet.
  • Should your children be getting more omega-3s in their diet? A recent study concluded that most American children only get 20-40 mg/day of DHA from their diet. So if your child’s food preferences don’t include salmon, sardines and the like – and if your child is experiencing learning issues or problems with ADHD, you might consider adding fish oil supplements to their diet. There’s no need to megadose. The international standard is around 200 mg/day of DHA for children 7 or older.
  • If you are one of those people who is confused by conflicting headlines about the benefits of supplementation, you may want to look at the studies behind those headlines and ask if supplementation would have been likely to provide any benefit in the subjects studied.

The Bottom Line:

1)     A recent study reported that supplementation with fish oil significantly improved learning skills in children consuming a diet that was deficient in omega-3 fatty acids.

2)     If your children are not consuming foods rich in omega-3 fatty acids such as coldwater fish, you might wish to make sure that they are getting adequate levels of omega-3 fatty acids in their diet. Most experts recommend around 200 mg/day for children over 7.

3)     This study also illustrates the principle that supplementation is most likely to be of demonstrable benefit to those who have the worst diets and the greatest need. That doesn’t mean that supplementation won’t benefit everyone, but it does mean that it may be difficult to prove the value of supplementation in healthy people consuming a good diet.

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.

 

Do Omega-3s Lower Blood Pressure?

The Good News About Fish Oil

Author: Dr. Stephen Chaney

High Blood PressureHigh blood pressure or hypertension is a major problem in this country. Over 60% of Americans have high blood pressure. Only 47% of those with hypertension are adequately controlled. 20% of them don’t even know that they have high blood pressure.

In this case, ignorance is definitely not bliss. That’s because high blood pressure significantly increases the risk of stroke, heart attacks and congestive heart failure.

The causes of high blood pressure are many. Genetics, obesity, lack of exercise, sodium, alcohol, saturated fats and too few fresh fruits and vegetables all play a role. Age also plays a role. As we age, our blood vessels become less flexible and our blood pressure rises by about 0.6 mm Hg per year.

Medications can help, but many of them have significant side effects and often aren’t fully effective in controlling blood pressure. That’s why natural approaches are so important.

Because there are so many causes of hypertension, natural approaches for lowering your blood pressure are not simple. Natural approaches start with weight loss, restricting sodium intake, increasing physical activity, moderating alcohol intake and something called the DASH diet. In short, there is not just one simple change that you can make that will totally eliminate hypertension. It requires a complete lifestyle change.

That’s why the latest study on the effect of omega-3s on blood pressure is so exciting. If the headlines are true, adding omega-3s to your diet may be one of the most effective things you can do to lower your blood pressure naturally. So let’s examine the study to see if the headlines are accurate.

How Was The Study Designed?

This study (Miller et al, American Journal of Hypertension, doi:10.1093/ajh/hpu024) was a very large, well designed study. It is a meta-analysis of 70 randomized, placebo controlled clinical studies. Key characteristics of these studies were:

  • The mean study duration was 69 days. That means these beneficial effects occur relatively quickly.
  • The mean EPA + DHA dose was 3.8 g/day (range = 0.2 – 15 g/day). A wide range of doses was included.
  • The EPA & DHA came from all sources (seafood, EPA+DHA fortified foods, fish oil, algal oil, and purified ethyl esters. The source did not affect the outcome.
  • Olive oil was the most commonly used placebo, with omega-6 vegetable oils being used as placebos in a few studies. The choice of placebo did not affect the outcome.
  • None of the people in these studies were taking blood pressure lowering medications. That means these studies were specifically designed to see whether omega-3s lowered blood pressure, not whether they had any additional benefit for people already taking medications. This is important because if you only focus on groups who are already taking multiple medications, you tend to obscure the beneficial effects of omega-3s (see my recent Health Tip “Is Fish Oil Really Snake Oil?”)

Do Omega-3s lower Blood Pressure?

Fish OilThe authors of the study reported that:

  • Compared to placebo, EPA+DHA reduced systolic blood pressure (that’s the upper reading) by 1.52 mm Hg and diastolic blood pressure (that’s the lower reading) by 0.99 mm Hg.
  • When they looked at those participants who already had high blood pressure, the numbers were even more impressive – a 4.51 mm Hg decrease in systolic blood pressure and a 3.05 mm Hg decrease in diastolic blood pressure. That’s important because for each 2 mm Hg reduction in blood pressure there is a 6% decrease in stroke mortality, a 4% decrease in heart disease mortality, and a 3% decrease in total mortality.

More to the point, the authors of the study concluded that “A decrease of 4.51 mm Hg in systolic blood pressure among those with high blood pressure could help an individual avoid having to take medication to control blood pressure levels”.

  • When they looked at the study participants who had normal blood pressure the numbers were still significant – a 1.25 mm Hg decrease in systolic blood pressure and a 0.62 decrease in diastolic blood pressure. The authors pointed out that this could prevent, or at least delay, the age-related progression towards hypertension.
  • The effect of omega-3s on systolic blood pressure (4.51 mm Hg decrease) was comparable to the most successful lifestyle interventions – 3-10 mm Hg decrease for 10 pound weight loss, 4-9 mm Hg decrease for increased physical activity, 2-8 mm Hg decrease for sodium restriction, and 2-4 mm Hg for decreased alcohol consumption.
  • A dose of at least 1 gm/day of EPA+DHA was required for a significant decrease in systolic blood pressure, and a dose of over 2 gm/day was required for a significant decrease in both systolic and diastolic blood pressure

While this is a single study, it is consistent with a number of previous studies in this area. Based on the existing body of literature I would recommend omega-3s as part of a holistic approach for keeping your blood pressure under control.

The Bottom Line:

1)     A recent meta-analysis of 70 published clinical studies (AJH, doi: 10.1093/ajh/hpu024) has shown fairly convincingly that omega-3 fatty acids are effective at lowering blood pressure. Moreover, this study is consistent with a number of previous studies. The evidence appears to be strong enough for omega-3s to be considered as part of a holistic approach to keeping your blood pressure under control.

2)     If you already have high blood pressure, you should know that omega-3s caused blood pressure to decrease by 4.51 mm Hg in people like you. The authors of the study concluded that this decrease in blood pressure is large enough that some people may be able to avoid blood pressure medicines entirely. For others addition of omega-3s to their diet will likely allow their physicians to reduce the dose of medications required to keep their blood pressure under control – thus minimizing the side effects of the medications.

3)     If you already have slightly elevated blood pressure that has not yet progressed to clinical hypertension, you should know that omega-3s also give a modest decrease in blood pressure in people like you. The authors of the study concluded that this decrease was enough to prevent or delay the age-related onset of hypertension.

4)     The effect of omega-3s on reducing blood pressure is equivalent to the most successful lifestyle changes (weight loss, increased physical activity, sodium restriction and alcohol moderation). That doesn’t mean that you should pop fish oil pills and forget the other lifestyle changes. The idea is to combine as many of those lifestyle changes as possible so that you may never have to worry about high blood pressure again.

5)     You need at least 1 gm/day of EPA+DHA to reduce systolic blood pressure and more than 2 gm/day to reduce both systolic and diastolic blood pressure.

6)     Contrary to the hype you may have been reading elsewhere, the source of EPA+DHA didn’t matter. The only caveat is that many people really struggle with trying to get 1-2 gm/day of EPA+DHA from fish. It’s a bit too much of a good thing.

7)     Don’t think of hypertension as a “Do it yourself” project. Hypertension is a silent killer. It’s one of those diseases where the first symptom is often sudden death – or, even worse, a life that is no longer worth living. Work with your physician. Let them help you find the right balance between lifestyle changes (including omega-3s) and medications to keep your blood pressure under control.

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.

Health Tips From The Professor