Are All Carbs Bad?

Are Low Carb Enthusiasts Right About The Dangers Of Carbohydrates?

Author: Dr. Stephen Chaney 

Low carb enthusiasts have been on the warpath against carbohydrates for years.

Almost everyone agrees that sugar-sweetened sodas and highly processed, refined foods with added sugar are bad for us. But low carb enthusiasts claim that we should also avoid fruits, grains, and starchy vegetables. Have they gone too far?

Several recent studies suggest they have. For example, both association studies and randomized controlled studies suggest that total carbohydrate intake is neither harmful nor beneficial for heart health.

In addition, recent studies suggest that free sugar intake is associated with both elevated triglyceride levels and an increase in heart disease risk.

But those studies have mostly looked at free sugar intake from sugar-sweetened sodas. The authors of this study (RK Kelley et al, BMC Medicine, 21:34, 2023) decided to look more carefully at the effect of all free sugars and other types of carbohydrates on triglyceride levels and heart disease risk.

How Was This Study Done?

clinical studyThe 110,497 people chosen for this study were a subgroup of participants in the UK Biobank Study, a large, long-term study looking at the contributions of genetic predisposition and environmental exposure (including diet) to the development of disease in England, Scotland, and Wales.

The participants in this study were aged between 37 and 73 (average age = 56) on enrollment and were followed for an average of 9.4 years. None of them had a history of heart disease or diabetes or were taking diabetic medications at the time of enrollment.

During the 9.4-year follow-up, five 24-hour dietary recalls were performed, so that usual dietary intake could be measured rather than dietary intake at a single time point. The people in this study participated in an average of 2.9 diet surveys, and none of them had less than two diet surveys.

The averaged data from the dietary recalls were analyzed for the amount and kinds of carbohydrate in the diet. With respect to the types of carbohydrate, the following definitions would be useful.

  • The term free sugars includes all monosaccharides and disaccharides added to foods by the manufacturer, cook, or consumer, plus sugars naturally present in honey, syrups, and unsweetened fruit juices.
  • The term non-free sugars includes all sugars not in the free sugar category, mostly sugars naturally occurring in fruits, vegetables, and dairy products.
  • The term refined grains includes white bread, white pasta, white rice, most crackers and cereals, pizza, and grain dishes with added fat.
  • The term whole grains includes wholegrain bread, wholegrain pasta, brown rice, bran cereal, wholegrain cereals, oat cereal, and muesli.

Finally, the study looked at the association of total carbohydrate and each class of carbohydrate defined above with all heart disease, heart attacks, stroke, and triglyceride levels.

Are All Carbs Bad?

Question MarkThe study looked at total carbohydrate intake, free sugar intake, and fiber intake. In each case, the study divided the participants into quartiles and compared those in the highest quartile with those in the lowest quartile.

Using this criterion:

  • Total carbohydrate intake was not associated with any cardiovascular outcome measured (total heart disease risk, heart attack risk, and stroke risk).
  • Free sugar intake was positively associated with all cardiovascular outcomes measured. Each 5% increase in caloric intake from free sugars was associated with a:
    • 7% increase in total heart disease risk.
    • 6% increase in heart attack risk.
    • 10% increase in stroke risk.
    • 3% increase in triglyceride levels.
  • Fiber intake was inversely associated with total heart disease risk. Specifically, each 5 gram/day increase in fiber was associated with a:
    • 4% decrease in total heart disease risk.

The investigators also looked at the effect of replacing less healthy carbohydrates with healthier carbohydrates. They found that:

  • Replacing 5% of caloric intake from refined grains with whole grains reduced both total heart disease risk and stroke risk by 6%.
  • Replacing 5% of caloric intake from free sugars (mostly sugar-sweetened beverages, fruit juices, and processed foods with added sugar) with non-free sugars (mostly fruits, vegetables, and dairy products) reduced total heart disease risk by 5% and stroke risk by 9%.

Are Low Carb Enthusiasts Right About The Dangers Of Carbohydrates?

With these data in mind let’s look at the claims of the low-carb enthusiasts.

Claim #1: Carbohydrates raise triglyceride levels. This study shows:

  • This claim is false with respect to total carbohydrate intake and high fiber carbohydrate intake (fruits, vegetables, and whole grains. This study did not measure intake of beans, nuts, and seeds, but they would likely be in the same category).
  • However, this claim is true with respect to foods high in free sugars (sugar-sweetened beverages, fruit juices, and processed foods with added sugar).

Claim #2: Carbohydrates increase heart disease risk. This study shows:

  • That claim is false with respect to total carbohydrate intake and high fiber carbohydrate intake.
  • However, this claim is true with respect to foods high in free sugars.

Claim #3: Carbohydrates cause weight gain [Note: Low carb enthusiasts usually word it differently. Their claim is that eliminating carbohydrates will help you lose weight. But that claim doesn’t make sense unless you believed eating carbohydrates caused you to gain weight.] This study shows:

  • This claim is false with respect to total carbohydrate intake and high fiber carbohydrate intake.
  • Once again, this claim is true with respect to foods high in free sugars.

The data with high fiber carbohydrates was particularly interesting. When the authors compared the group with the highest fiber intake to the group with the lowest fiber intake, the high-fiber group:

  • Consumed 33% more calories per day.
  • But had lower BMI and waste circumference (measures of obesity) than the low-carbohydrate group.

This suggests that you don’t need to starve yourself to lose weight. You just need to eat healthier foods.

And, in case you were wondering, the high fiber group ate:

  • 5 more servings of fruits and vegetables and…
  • 2 more servings of whole grain foods than the low fiber group.

This is consistent with several previous studies showing that diets containing a lot of fruits, vegetables, and whole grains are associated with a healthier weight.

The authors concluded, “Higher free sugar intake was associated with higher cardiovascular disease incidence and higher triglyceride concentrations…Higher fiber intake and replacement of refined grain starch and free sugars with wholegrain starch and non-free sugars, respectively, may be protective for incident heart disease.”

In short, with respect to heart disease, the type, not the amount of dietary carbohydrate is the important risk factor.

What Does This Mean For You?

Questioning WomanForget the low carb “mumbo jumbo”.

  • Carbohydrates aren’t the problem. The wrong kind of carbohydrates are the problem. Fruit juice, sugar-sweetened sodas, and processed foods with added sugar:
    • Increase triglyceride levels.
    • Are associated with weight gain.
    • Increase the risk for heart disease.
  • In other words, they are the villains. They are responsible for the bad effects that low carb enthusiasts ascribe to all carbohydrates.
  • Don’t fear whole fruits, vegetables, dairy, and whole grain foods. They are the good guys.
    • They have minimal effect on triglyceride levels.
    • They are associated with healthier weight.
    • They are associated with a lower risk of heart disease and diabetes.

So, the bottom line for you is simple. Not all carbs are created equal.

  • Your mother was right. Eat your fruits, vegetables, and whole grains.
  • Avoid fruit juice, sodas and other sugar-sweetened beverages, and processed foods with added sugar. [Note: Artificially sweetened beverages are no better than sugar-sweetened beverages, but that’s another story for another day.]

And, if you were wondering why low carb diets appear to work for weight loss, it’s because any restrictive diet works short term. As I have noted previously, keto and vegan diets work equally well for short-term weight loss.

The Bottom Line 

Low carb enthusiasts have been telling us for years to avoid all carbohydrates (including fruits, starchy vegetables, and whole grains) because carbohydrates:

  • Increase triglyceride levels.
  • Cause weight gain.
  • Increase our risk for heart disease.

A recent study has shown that these claims are only true for some carbohydrates, namely fruit juices, sodas and other sugar-sweetened beverages, and processed foods with added sugar.

Whole fruits, vegetables, and whole grain foods have the opposite effect. They:

  • Have a minimal effect on triglyceride levels.
  • Are associated with a healthier weight.
  • Are associated with a lower risk of heart disease and diabetes.

So, forget the low carb “mumbo jumbo” and be sure to eat your fruits, vegetables, and whole grains.

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

Do Whole Grains Reduce Inflammation?

Are Low Carb Diets Healthy Long Term?

Author: Dr. Stephen Chaney 

InflammationInflammation is a bit like Dr. Jekyll and Mr. Hyde. Acute inflammation plays a valuable role in our immune response. But chronic inflammation is a scourge. Chronic inflammation:

  • Is a key component of all the “itis” diseases.
  • Can lead to autoimmune diseases.
  • Is thought to play an important role in heart disease.
  • Is associated with many other diseases, such as diabetes, cancer, Alzheimer’s disease, and inflammatory bowel diseases (IBS).

While there are many causes of chronic inflammation, diet plays an important role. In a previous issue of “Health Tips From the Professor” I have described how an anti-inflammatory diet can quell the fires of chronic inflammation.

Fiber from unprocessed plant foods is a key component of an anti-inflammatory diet. But are all plant fibers equally effective at reducing inflammation? Here is what we know:

  • Fiber from whole grains, vegetables, and fruits have different chemical and physical characteristics and support the growth of different species of friendly bacteria in our intestines.
  • Previous studies have shown that higher intakes of dietary fiber are associated with lower risk of heart disease.
    • Studies have suggested that fiber from whole grains may be more effective than fiber from fruits and vegetables at reducing heart disease risk.
  • Chronic inflammation is highly associated with the development of heart disease. This has led to the hypothesis that fiber from whole grains may be more effective than other plant fibers at reducing chronic inflammation.
    • Some studies have supported this hypothesis, but they have all been done with middle-aged participants, not with elderly participants who characteristically have higher levels of inflammation.

The study (R Shivakoti et al, JAMA Network Open, 5(3): e225012, 2022) I will describe today was designed to:

  • Test the hypothesis that whole grain fiber is more effective than vegetable or fruit fiber at reducing inflammation.
  • Determine how important reducing inflammation is at reducing the risk of heart disease.
  • Extending these findings to an older population group.

How Was The Study Done?

Clinical StudyThe data for this study was obtained from the Cardiovascular Health Study (CHS), a study designed to characterize factors influencing cardiovascular health in American adults aged 65 years or older. This study analyzed data from 4,125 participants (40% men, 95% white) who enrolled in the CHS study from 1989 to 1990.

These participants did not have heart disease at the time they were enrolled in the study. They had an average age of 72.6 at the beginning of the study and were followed for an average of 11.9 years. During that time 1,941 (47%) of them developed heart disease.

When the participants were enrolled in the study:

  • A food frequency questionnaire was administered to them by a trained dietitian to assess their long-term usual dietary intake. This information was used to assess:
    • Their total fiber intake and…
    • Their fiber intake from various dietary sources (whole grains, vegetables, and fruits).
  • Fasting blood samples were collected and used to analyze various markers of inflammation.

A follow-up via phone was conducted every 6 months to track an initial diagnosis of cardiovascular disease.

At the end of the study, the investigators analyzed:

  • The effect of total fiber and fiber from different food sources on the risk of developing heart disease.
  • The effect of total fiber and fiber from different food sources on inflammatory markers in the blood.
  • The extent to which decreased inflammation could explain the effect of whole grain fiber on reducing heart disease.

Do Whole Grains Reduce Inflammation?

With respect to inflammation:

  • Increased intake of total fiber was associated with healthier levels of the inflammatory markers CRP, IL-1RA, and sCD163.
    • Increased intake of fiber from whole grains was associated with healthier levels of the inflammatory markers CRP, IL-6, and IL-1RA.
    • Increased intake of vegetable fiber was not significantly associated with healthier levels of any inflammatory marker.
    • Increased intake of fiber from fruits was associated with healthier levels of the inflammatory marker sCD163.

With respect to cardiovascular disease:

  • Every 5g/day increase in total fiber decreased the risk of heart disease by 5%.
    • Every 5g/day increase in fiber from whole grains decreased the risk of heart disease by 14%.
    • Increased intake of fiber from vegetables and fruits did not have a statistically significant effect on the risk of heart disease.

Finally, when the investigators did a statistical analysis to determine to extent to which the effect of whole grain fiber on inflammation, could explain its effect on heart disease, they concluded:

  • The effect of whole grain fiber on inflammation could explain only about 16% of its effect on heart disease.

In the words of the authors, “In this prospective study of older adults, higher intakes of total fiber were associated with lower levels of various inflammatory markers, and this inverse association was primarily due to cereal fiber intake. Vegetable and fruit fiber intakes were not consistently associated with lower levels of inflammatory markers. These results suggest that specifically cereal fibers might be more effective in reducing systemic infection, which will need to be tested in interventional studies of specific populations.

In addition, cereal fiber was associated with a lower risk of CVD, although inflammation mediated less than 20% of the observed inverse association between cereal fiber and CVD. This suggests that the association of cereal fiber is primarily due to factors … other than systemic inflammation.”

Note: This conclusion underplays the role of fruit fiber in reducing inflammation. The statement is correct in saying only whole grain fiber reduces the inflammatory markers CRP, IL-6, and IL-1RA. However, both total fiber and fruit fiber increase the anti-inflammatory marker sCD163. That is why I chose to use the term “healthier levels” rather than lower or higher levels when describing the effects of whole grain and fruit fibers on markers of inflammation.

What Does This Study Mean For You?

confusion#1: The biggest takeaway from this study is that whole grains are good for you.

  • This study shows that whole grain fiber decreases our risk of developing heart disease.
    • This is fully consistent with multiple previous studies showing that whole grains decrease the risk of heart disease.
    • Previous studies have also shown that whole grains reduce the risk of cancer and diabetes.
  • This study also suggests that whole grain fiber reduces chronic inflammation.

There are also some takeaways from this and previous studies that may not be so obvious.

#2: Fiber has many important benefits beyond its effect on inflammation. For example:

  • This study concluded that the reduction in inflammation only explained a small part of the beneficial effect of whole grain fiber on reducing heart disease risk.
  • That is because whole grain fiber also:
    • Feeds friendly bacteria that improve gut function.
    • Provides satiety that can result in reduced fat and calorie intake.
    • Binds cholesterol, which improves blood cholesterol level.
    • Slows the rate at which dietary sugar enters the bloodstream, which improves blood sugar control.

#3: Whole plant foods have many benefits beyond their fiber content.

  • This study concluded that whole grain fiber was more beneficial than fiber from fruits and vegetables at reducing inflammation and reducing the risk of heart disease.
  • Previous studies have also shown that fruit and vegetables significantly decrease the risk of heart disease, stroke, and cancer.
  • That is because whole grains and unprocessed fruits and vegetables:
    • Displace sugar, refined flour, and highly processed foods from the diet.
    • Have a lower caloric density than processed foods, making it easier to achieve a healthy weight.
    • Provide nutrients and phytonutrients not found in processed foods.
    • Support a wide variety of healthy gut bacteria.

Are Low Carb Diets Healthy Long Term?

low carb dietconfusionWhen you consider all the benefits of whole grains, fresh fruits, and vegetables, it brings us to the final take home message.

#4: Despite what Dr. Strangelove has told you, low-carb diets may not be healthy long term.

  • There are no long-term (10 or 20-year) studies of low-carb diets. We simply have no evidence to support the claim that they are healthy long term.
  • Most low-carb diets eliminate or severely limit fruits and whole grains. Considering the many health benefits they provide, it is unlikely that any diet that restricts them is healthy long term.

The Bottom Line 

A recent study looked at the effect of plant fiber on inflammation and on heart disease.

With respect to inflammation the study found:

  • Increased intake of total fiber was associated with healthier levels of the inflammatory markers CRP, IL-1RA, and sCD163.
    • Increased intake of fiber from whole grains was associated with healthier levels of the inflammatory markers CRP, IL-6, and IL-1RA.
    • Increased intake of vegetable fiber was not significantly associated with healthier levels of any inflammatory marker.
    • Increased intake of fiber from fruits was associated with healthier levels of the inflammatory marker sCD163.

With respect to cardiovascular disease:

  • Every 5g/day increase in total fiber decreased the risk of heart disease by 5%.
  • Every 5g/day increase in fiber from whole grains decreased the risk of heart disease by 14%.
    1. The biggest takeaway from this study is that whole grains are good for you.

 Other takeaways from this and previous studies are:

2) Fiber has many important benefits beyond its effect on inflammation.

3) Whole plant foods have many benefits beyond their fiber content.

4) Despite what Dr. Strangelove has told you, low-carb diets may not be healthy long term.

For more details 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.

Can Diet Add Years To Your Life?

Which Foods Have The Biggest Effect On Longevity? 

Author: Dr. Stephen Chaney

Fountain Of YouthEveryone over 50 is searching for the elusive “Fountain Of Youth”.

  • We want to look younger.
  • We want to feel younger.
  • We want the energy we had in our 20s.
  • We want to be rid of the diseases of aging.

The list goes on!

But how do we do that? Pills and potions abound that claim to reverse the aging process. Most just reverse your wallet.

  • Should we train for marathons or bodybuilding contests?
  • Should we meditate or do yoga to relieve stress?
  • Should we get serious about losing weight?
  • Should we get more sleep?
  • Is there some miracle diet that can slow the aging process?

All the above probably slow the aging process, but the evidence is best for the effect of diet on aging. Several recent meta-analyses have looked at the effect of diet on the risk of premature deaths. In this issue of “Health Tips From the Professor” I review a study (LT Fadnes et al, PLoS Medicine, February 8, 2022) that combines the best of these meta-analyses into a single database and provides a provocative insight into the effect of diet on longevity.

How Was This Study Done?

Clinical StudyThis study combined data from recent meta-analyses looking at the impact of various food groups on the risk of premature deaths with the Global Burden of Disease Study which provides population-level estimates of life years lost due to dietary risk factors.

The authors then developed a new algorithm that allowed them to estimate how different diets affect sex- and age-specific life expectancy.

They divided the population into three different diet categories based on their intake of whole grains, vegetables, fruits, nuts, legumes, fish, eggs, dairy, refined grains, red meat, processed meat, white meat, sugar-sweetened beverages, and added plant oils. The diet categories were:

  • Typical Western Diet (TW). This diet was based on average consumption data from the United States and Europe. This was their baseline.
  • Optimal diet (OD). This diet is similar to a vegan or semi-vegetarian diet. However, it was not a purely vegan diet nor a purely semi-vegetarian diet. Instead, it represented the best diet people in this study were consuming.
  • Feasibility diet (FA). This diet recognizes that few people are willing to make the kind of changes required to attain an optimal diet. It is halfway between the Typical Western Diet and the Optimal Diet.

To help you understand these diets based on the foods the study participants were eating, here are the comparisons in terms of daily servings:

Food TW Diet FA Diet OD Diet
Whole grains 1.5 servings 4.3 servings 7 servings
Vegetables 3 servings 4 servings 5 servings
Fruits 2.5 servings 3.75 servings 5 servings
Nuts 0 serving* 0.5 serving* 1 serving*
Legumes 0 serving** 0.5 serving** 1 serving**
Fish 0.25 serving 0.5 serving 1 serving
Eggs 1 egg 0.75 egg 0.5 egg
Dairy 1.5 servings 1.25 servings 1 serving
Refined grains 3 servings 2 servings 1 serving
Red meat 1 serving 0.5 serving 0 serving
Processed meat 2 servings 1 serving 0 serving
White meat 0.75 serving 0.6 serving 0 serving
Sugar-sweetened beverages 17 oz 8.5 oz 0 oz
Added plant oils 2 tsp 2 tsp 2 tsp

*1 serving = 1 handful of nuts

**1 serving = 1 cup of beans, lentils, or peas

Using their algorithm, the authors asked what the effect on longevity would be if people changed from a typical western diet to one of the other diets at age 20, 60, or 80 and maintained the new diet for at least 10 years. The 10-year requirement is based on previous studies showing that it takes around 10 years for dietary changes to affect the major killer diseases like heart disease, cancer, or diabetes.

Finally, the authors improved the accuracy of their estimates of the effect of diet on longevity by taking into account the quality of each study included in their analysis. I will discuss the importance of this below.

Can Diet Add Years To Your Life?

The results were impressive.

The authors estimated that if people in the United States were to change from a typical western diet to an “optimal diet” and maintain it for at least 10 years,

…starting at age 20, men would live 13 years longer and women would live 10.7 years longer.

…starting at age 60, men would live 8.8 years longer and women would live 8 years longer.

…starting at age 80, both men and women would live 3.4 years longer.

But what if you weren’t a vegan purist? What if you only made half the changes you would need to make to optimize your diet? The news was still good.

The authors estimated that people in the United States were to change from a typical western diet to a “feasibility diet” and maintain it for at least 10 years,

…starting at age 20, men would live 7.3 years longer and women would live 6.2 years longer.

…starting at age 60, men would live 4.8 years longer and women would live 4.5 years longer.

…starting at age 80, both men and women would live ~2 years longer.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.”

Which Foods Have The Biggest Effect On Longevity?

The algorithm the authors developed also allowed them to look at which foods have the biggest effect on longevity. The authors estimated when changing from a typical western diet to an optimal diet, the greatest gains in longevity were made by eating:

  • More legumes, whole grains, and nuts, and…
  • Less red and processed meat.

The authors concluded, “An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains [in longevity].”

However, this conclusion needs to be interpreted with caution. We also need to recognize that an “optimal diet” was defined as the best diet people in this study were eating. In addition, the effect of different foods on longevity depends on:

  • The quality of the individual studies with that food, and…
  • The difference in consumption of that food in going from a western diet to an optimal diet.

For example:

  • Legumes, whole grains, nuts, red & processed meat made the list because the quality of data was high and the difference in consumption between the typical western diet and optimal diet was significant.
  • The quality of data for an effect of fruits and vegetables was also high. For example, one major study concluded that consuming 10 servings a day of fruits and vegetables a day reduces premature death by 31% compared to consumption of less than 1 serving a day. However, the difference in consumption of fruits and vegetables between the western and optimal diets in this study was small, so fruits and vegetables didn’t make the list.
  • Eggs and white meat didn’t make the list because the quality of data was low for those foods. Simply put,  that means that there was a large variation in effect of those foods on longevity between studies.
  • Other foods didn’t make the list because the quality of data was only moderate and/or the difference in intake was small.

So, the best way to interpret this these data is:

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve these benefits. In the words of the authors, “Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

What Does This Study Mean For You?

This study is the best of many studies showing the benefit of a more plant-based diet on health and longevity. It particularly encouraging because it shows:

  • You can achieve significant benefit by switching to a more plant-based diet late in life. You get the biggest “bang for your buck” if you switch at age 20. But even making the switch at age 60 or 80 was beneficial.
  • You don’t need to be a “vegan purist”. While the biggest benefits were seen for people who came close to achieving a vegan or semi-vegetarian diet, people who only made half those changes saw significant benefits.

As I said above, this is a very strong study. However, the underlying data come from association studies, which can have confounding variables that influence the results.holistic approach

For example, people who eat more plant-based diets tend to weigh less and exercise more. And both of those variables can influence longevity. Each study attempted to statistically correct for those variables, but they still might have a slight influence on the results.

However, I don’t see that as a problem because, in my view, a holistic approach is always best. As illustrated on the right, we should be seeking a lifestyle that includes a healthy diet, weight control, and exercise.

As for supplementation, both the vegan and semi-vegetarian diets tend to leave out whole food groups. Unless you are married to a dietitian, that means your diet is likely to be missing important nutrients.

The Bottom Line

A recent study asked whether changing from the typical western diet to a healthier, more plant-based diet could influence longevity. The results were very encouraging. The study showed that:

  • Changing to a healthier diet could add up to a decade to your lifespan.
  • The improvement in lifespan was greatest for those whose diets approached a vegan or semi-vegetarian diet, but a significant improvement in lifespan was seen for people who made only half those dietary improvements.
  • The improvement in lifespan was greatest for those who switched to a healthier diet in their 20’s, but significant improvements in lifespan were seen for people who didn’t change their diet until their 60’s or 80’s.

In terms of the foods that have the biggest effect on longevity.

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve those benefits.
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.

An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains. Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”

For more details about 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.

Do Whole Grains Keep Diabetes Away?

Are Whole Grains Healthy? 

Author: Dr. Stephen Chaney

deceptionLow carb enthusiasts will tell you that carbohydrates are the villain. They tell you that cutting carbohydrates out of your diet will reduce your risk of obesity, diabetes, heart disease, and cancer.

If they limited their list of villainous foods to highly processed foods with white flour and/or added sugars, many nutrition experts would agree with them. There is widespread agreement in the nutrition community that we eat far too much of these foods.

However, I don’t have to tell you that many low carb diets also eliminate whole grains, fruits, and beans from their diets based solely on the carbohydrate content of these foods. Is this good advice? Is there any data to back up this claim?

The short answer is no. Last week I shared a study showing that fruits reduced your risk of developing type 2 diabetes.

This week I will review a study looking at the effect of whole grain consumption on the risk of developing type 2 diabetes.

How Was This Study Done?

Clinical StudyThis study combined data from women in the Nurses’ Health Study (1984-2014) and the Nurses’ Health Study II (1991-2017), and men in the Health Professionals Follow-Up Study (1986-2016). There were 158,259 women and 36,525 men in these three studies.

None of the participants had type 2 diabetes, cardiovascular disease, or cancer at the time they entered the studies.

At the beginning of each study and every 4 years later the participants were asked to fill out a food frequency questionnaire to collect information about their usual diet over the past year. Validation studies showed that the diets of the participants changed little over the interval of the studies. [Note: This is a strength of these studies. Many clinical studies only collect dietary data at the beginning of the study, so there is no way of knowing whether the participant’s diets changed over time.]

The participants in these studies were followed for an average of 24 years. They were sent follow-up questionnaires every two years to collect information on diseases they had been diagnosed with over the past two years. Participants who reported type 2 diabetes were sent a supplementary questionnaire to confirm the diagnosis.

This study measured the effect of whole grain consumption, and frequently consumed whole grain foods, on the long term (24 year) risk of developing type 2 diabetes.

The data were adjusted for multiple possible confounding variables (other factors that might affect the risk of developing type 2 diabetes) including age, ethnicity, smoking status, alcohol intake, multivitamin use, healthy eating index (a measure of how healthy the overall diet was), caloric intake, obesity, family history of diabetes, and use of oral contraceptives or postmenopausal hormones.

In addition, a stratified analysis was performed to assess the extent to which obesity, physical activity, smoking status, and family history of diabetes influenced the outcome.

In short, this was a very rigorous and well-controlled study.

Do Whole Grains Keep Diabetes Away?

Whole GrainsTotal whole grain consumption was divided into five groups ranging from 2 servings per day to < 0.1 serving per day. When participants with the highest whole grain intake were compared to those with the lowest whole grain intake:

  • Whole grain consumption was associated with a 29% lower risk of developing type 2 diabetes.
    • The association between whole grain consumption and reduced risk of developing type 2 diabetes was stronger for lean individuals (45% reduction in risk) than for overweight (34% reduction in risk) or obese individuals (23% reduction in risk).
    • The association between whole grain consumption and reduced risk of developing type 2 diabetes was not affected by physical activity, smoking status, or family history of diabetes.

When they looked at the entire range of whole grain intake among participants in the study:

  • The risk reduction for developing type 2 diabetes was nonlinear.
    • The greatest portion of risk reduction (30% decreased risk) occurred between 0 and 2 servings/day.
    • However, the reduction in risk continued to decrease at a slower rate up to 4.5 servings/day (38% decreased risk), the highest intake recorded for participants in this study.

When they looked at the most frequently consumed whole grain foods and compared the risk of developing type 2 diabetes for participants consuming one or more servings per day compared with less than 1 serving per month:

  • People consuming whole grain cold breakfast cereals were 19% less likely to develop type 2 diabetes.
  • People consuming whole grain breads were 21% less likely to develop type 2 diabetes.
  • People consuming popcorn were 8% more likely to develop type 2 diabetes.

Once again, the risk reduction was nonlinear.

  • For whole grain cold breakfast cereals risk reduction plateaued at around 0.5 servings per day.
  • For whole grain breads the greatest portion of risk reduction occurred at around 0.5 servings per day (17% decreased risk), but the reduction in risk continued to decrease at a slower rate up to 4 servings/day (28% decreased risk).
  • For popcorn, the risk reduction curve was non-linear. There was a slight, non-significant, decrease in risk at about 0.2 servings per day, followed by a steady increase in risk up to 1.75 servings per day (24% increased risk).

When they looked at less frequently consumed whole grain foods and compared the risk of developing type 2 diabetes for participants consuming two or more servings per week compared with less than 1 serving per month:

  • People consuming oatmeal were 21% less likely to develop type 2 diabetes.
  • People consuming brown rice were 12% less likely to develop type 2 diabetes.
  • People consuming added bran were 15% less likely to develop type 2 diabetes.

There were not enough people consuming these whole grains for the investigators to determine how many servings were optimal.

The authors concluded, “Higher consumption of total whole grains and several commonly eaten whole grain foods, including whole grain breakfast cereal, oatmeal, whole grain bread, brown rice, and added bran, was significantly associated with a lower risk of type 2 diabetes. These findings provide further support for the current recommendations of increasing whole grain consumption as part of a healthy diet for the prevention of type 2 diabetes.”

Are Whole Grains Healthy?

Question MarkThis is a very impressive study. As described above, it is a large (194,784 participants), long lasting (24 years), and well-designed study. With this data in mind, we can answer several important questions.

Are Whole Grains Healthy?

This study explodes the myth that you should avoid whole grains if you want to prevent diabetes. Instead, the study shows that whole grain consumption decreases your risk of developing type-2 diabetes.

I recently reviewed another large, well-designed study showing that whole grain consumption reduces your risk of dying from heart disease, cancer, and all causes combined.

So, clearly whole grains are good for you. They should be an important part of your diet.

Which Whole Grains Are Healthy?

According to this study, whole grain breakfast cereals, whole grain breads, oatmeal, brown rice, and bran are all healthy. All of them significantly reduce your risk of developing type 2 diabetes. Other whole grains are likely to be healthy too, but Americans consume so little of them, they could not be analyzed in this study.

However, there are some caveats:

  • You have to read labels carefully. Unless it says “100% whole grain”, it probably contains more refined grains than whole grains.
    • Yes, food manufacturers are intentionally deceptive. Who knew?
  • You have to look at the food, not just “whole grain” on the label.
    • It is hard to imagine, but Dr. Kellogg originally created breakfast cereals as health food. However, today many “whole grain” cereals are loaded with sugar and artificial ingredients. They are highly processed foods that are anything but healthy.
    • The case of popcorn is a perfect example. Popcorn is loaded with fiber. It should reduce your risk of diabetes. However, in this study it increased the risk of diabetes. That’s because 70% of the popcorn that Americans consume is purchased either pre-popped or ready to pop. It contains unhealthy ingredients like salt, butter, sugar, trans fats, and artificial flavors. It is a highly processed food. Air popped popcorn without the added ingredients is probably very healthy.

Why Are Whole Grains Healthy?

Dr. Strangelove and his buddies have told you to avoid all grains because they contain carbohydrates that are converted to sugar. That is good advice for refined grains. Not only are they rapidly converted to sugar. But they are also found in highly processed foods along with sugar, fat, and a witch’s brew of chemicals.

However, whole grains are different. Yes, whole grains are carbohydrate-rich foods, and the carbohydrate is converted to sugar during digestion. But:

  • They also contain fiber, which slows the digestion of the carbohydrate and delays the absorption of the sugar released during digestion.
  • The carbohydrate is trapped in a cellular matrix, which must be digested before the carbohydrate can be released.

In addition:

  • Whole grains contain nutrients and phytonutrients not found in refined grains.
  • The fiber in whole grains supports the growth of friendly bacteria in the gut.

How Many Whole Grain Foods Should I Be Eating?

This study found that you get the biggest “bang for your buck” when you go from 0 to around 2 servings per day of whole foods.

  • If you aren’t fond of whole grain foods, that is good news. It is also in line with USDA recommendation that half the grains we eat should be whole grains. You don’t need to eat whole grains with every meal.
  • If you are a purist, you can reduce your diabetes risk even more by increasing your whole grain intake up to at least 4.5 servings per day, the highest intake measured in this study.

Are Low Carb Diets Healthy?

Low carb diets may be effective for short term weight loss, but there is no evidence that they are healthy long term. And, because they cut out one or more food groups many experts feel they are likely to be unhealthy long term.

My advice is to forget “low carb” and focus on “healthy carb” instead.

  • Eliminate refined carbs and the highly processed foods they are found in.
  • Include fruits, whole grains, and beans as part of your diet. They are high carbohydrate foods, but, as this and other studies have shown, the carbohydrates in those foods are healthy carbs.

The Bottom Line

Low carb enthusiasts tell you to eliminate whole grains from your diet if you want to reduce your risk of developing diabetes. Is this true? Is it good advice?

A recent study put this advice to the test. It was a large (194,784 participants), long lasting (24 years), and well-designed study. Here is what the study found.

When participants with the highest whole grain intake were compared to those with the lowest whole grain intake:

  • Whole grain consumption was associated with a 29% lower risk of developing type 2 diabetes.

When they looked at the entire range of whole grain intake among participants in the study:

  • The risk reduction for developing type 2 diabetes was nonlinear.
  • The greatest portion of risk reduction (30% decreased risk) occurred between 0 and 2 servings/day.
  • But the reduction in risk continued to decrease at a slower rate up to 4.5 servings/day (38% decreased risk), the highest intake recorded for participants in this study.

When they looked at individual foods, whole grain breakfast cereals, whole grain bread, oatmeal, brown rice, and added bran all reduced diabetes risk.

The authors concluded, “Higher consumption of total whole grains and several commonly eaten whole grain foods, including whole grain breakfast cereal, oatmeal, whole grain bread, brown rice, and added bran, was significantly associated with a lower risk of type 2 diabetes. These findings provide further support for the current recommendations of increasing whole grain consumption as part of a healthy diet for the prevention of type 2 diabetes.”

For more details about 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.

Is The Paleo Diet Based On A Myth?

Are Starchy Foods Bad For Us? 

Author: Dr. Stephen Chaney

the paleo dietThe Paleo Diet is still very popular. And it does have its good points. It is a whole food diet. It eliminates sodas, junk foods, and highly processed foods. Any diet that does that can’t be all bad.

But is it unnecessarily restrictive? It eliminates starchy foods like grains, beans, peas, and corn. It is true that widespread consumption of these foods did not occur until after the agricultural revolution some 12,000 years ago. Our paleolithic ancestors probably did not consume significant quantities of these foods.

But did they consume other starchy foods? Our ideas about this have come primarily from comparing the diets of modern man with the diets of the few primitive hunter-gatherer populations that currently exist in our world. Based on that comparison, some Paleo advocates have concluded that the paleolithic diet contained few, if any, starchy foods.

More importantly, some Paleo advocates have gone a step further to assert that our bodies are not designed to eat starchy foods. They claim that foods like grains, legumes, corn, and potatoes are bad for us. They should be avoided.

How can we test whether these claims are true? After all, we don’t have any way of directly determining whether our paleolithic ancestors ate starchy foods or not. Or do we? That question is the topic of a new study (JA Fellows et al, PNAS, 118 No. 20 e2021655118 I will share with you today.

But first I need to acquaint you with what starch is and how we digest it. Once again, it is time for Biochemistry 101.

Biochemistry 101

professor owlStarch is simply a long polymer of glucose molecules. Digestion of starch starts in our mouth. Our saliva contains an enzyme called alpha-amylase that breaks the bond between adjacent glucose molecules. Alpha-amylase breaks starch down sequentially, first to maltodextrin (a shorter polymer of glucose molecules), then to maltose (two glucose molecules), and finally to glucose.

[Note: The nutrition gurus that tell you to read labels and avoid foods with maltodextrin are ignoring the fact that we produce maltodextrin naturally whenever we digest starch in the foods we eat.]

All humans contain the alpha-amylase gene. Simply put, that means that all humans have the potential to digest starchy foods.

However, not all humans have the same number of copies of the alpha-amylase gene. When we habitually consume a diet containing starchy foods, our bodies duplicate the alpha-amylase gene until our saliva contains enough alpha-amylase to easily digest the amount of starchy foods we are consuming. Simply put, that means our bodies are designed to easily adapt to the amount of starchy foods in our diet.

Most modern human populations have between six and 30 copies of the alpha-amylase gene. Our saliva contains a lot of alpha-amylase. However, the few primitive hunter-gatherer societies that still exist in our world have only two or three copies of the alpha-amylase gene. Their saliva contains very little alpha-amylase.

It is this difference that has led to the hypothesis that our paleolithic ancestors did not possess salivary alpha-amylase, which implies they didn’t eat starchy foods. This hypothesis also assumes that humans only began producing significant quantities of salivary alpha-amylase after the agricultural revolution when starchy foods like grains, rice, and beans became widely available.

This hypothesis is one of the central tenets of the Paleo diet. But we need to remember that it is just a hypothesis. It has not been directly tested because we thought there was no way to determine the starch content of the paleolithic diet – until now. However, before we get to the study that explodes this hypothesis, I want to revisit the Paleo Diet myths I described in an earlier issue of “Health Tips From The Professor”. I call this next section “Unicorns And The Paleo Diet”.

Unicorns And the Paleo Diet

the paleo diet and unicornsI titled this section “Unicorns and the Paleo Diet” because both are myths. In fact, the Paleo Diet is based on several myths.

Myth #1: Our ancestors all had the same diet. What we currently know as the Paleo diet is based on the diets of a few primitive hunter-gatherer societies that still exist in some regions of the world. However, when you look at the data more carefully, you discover that the diet of primitive societies varies with their local ecosystems.

The “Paleo diet” is typical of ecosystems in which game is plentiful and fruits and vegetables are less abundant or are seasonal. In ecosystems where fruits and vegetables are abundant, primitive societies tend to be more gatherers than hunters. They eat more fruits and vegetables and less meat.

The assumption that starchy foods were absent in the paleolithic diet is also a myth. For some primitive societies, starchy fruits or starchy roots are a big part of their diet. In short, our paleolithic ancestors ate whatever nature provided.

Myth #2: Our genetic makeup is hardwired around the “paleolithic diet”. In fact, humans are very adaptable. We are omnivores, which means we can eat whatever nature provides. We are designed to thrive in a wide variety of ecosystems. It is this adaptability that has allowed us to expand to every nook and cranny of the world.

For example, the enzymes needed to digest grains are all inducible, which means the body can turn them on when needed. Our paleolithic ancestors may not have eaten much grain, but we can very quickly adapt to the introduction of grains into our diet. As I described above, for alpha-amylase this adaptation occurs through gene duplication.

Myth #3: Our paleolithic ancestors were healthier than modern man: It some respects, the paleolithic diet is healthy, as I mentioned above. However, we need to remember that our paleolithic ancestors rarely lived past 30 or 40. They simply did not live long enough to experience degenerative diseases like heart disease and cancer. We have no idea whether a diet that served our paleolithic ancestors well will keep us healthy into our 70s, 80s and beyond.

How Was This Study Done?

Clinical StudyThis is a fascinating study, and one that would have been impossible just a few years ago. As I have described in previous issues of “Health Tips From the Professor”, studies on our microbiome, the bacteria that inhabit our bodies, is a rapidly evolving area of research.

When we talk about our microbiome, we generally think about our gut bacteria. However, the term “microbiome” includes all the bacteria that reside in our body, including those that reside in our oral mouth.

And, like our gut bacteria, the species of bacteria that reside in our mouth are heavily dependent on the foods we eat. Specifically, there are three species of oral bacteria that thrive on starch. They possess an “amylase binding protein” that allows them to capture salivary alpha-amylase and use it to break down dietary starch so they can use it as an energy source.

Consequently, the abundance of these three bacterial species in the oral microbiome is a precise marker for the amount of starch in a person’s diet. More importantly, high throughput DNA sequencing and supercomputers have made it simple to sequence all the bacteria in the oral microbiome and quantify the relative abundance of these three bacterial species.

You are probably thinking, “That’s fine, but how could you possibly determine the abundance of those bacteria in the mouth of a paleolithic human?” Here is where it gets really interesting!

The bacteria in our mouth form biofilms on our teeth, something we refer to as plaque. If the plaque remains on our teeth long enough, it calcifies, forming what is referred to as dental calculus (tooth tartar).

In the modern world we remove dental biofilms by brushing after every meal. We remove dental plaque and tartar by semi-annual visits to the dentist. But these are recent developments. They are not something our ancestors did.

Our ancestors simply accumulated dental calculus during their lifetime. More importantly, the dental calculus excluded air and water, so it preserved the DNA of the bacteria in their oral microbiome. That was the basis of the current study.

The study was a collaboration of 50 scientists over a 7-year period. The scientists sequenced 124 oral microbiomes from humanoid species in Africa, including Neanderthals (430,000 to 40,000 years ago), Late Pleistocene (129,000 to 11,700 years ago) humans, and modern-day humans.

Bacterial DNA from modern-day humans was obtained from dental calculus obtained during routine dental cleaning procedures by practicing dentists. The older DNA samples were obtained from dental calculus in the teeth of skeletal remains. The oldest DNA sample was obtained from a Neanderthal that lived around 100,000 years ago.

For comparison they also obtained bacterial DNA from the dental calculus of chimpanzees and gorillas, man’s closest primate relatives.

The species of bacteria in the oral microbiome from all these samples were determined by high throughput sequences and computerized analysis using high speed supercomputers.

Is The Paleo Diet Based On A Myth?

Question MarkThere were three important findings from this analysis:

  1. The species of bacteria in the oral microbiome of Neanderthals and Late Pleistocene humans was much more diverse than for modern humans. This suggests that their diets were more diverse (perhaps depending on what foods were available in their environment), while modern diets have become more standardized.

2) The species of bacteria that thrive on starchy foods were remarkably constant in the oral microbiome of all human species from Neanderthals to Late Pleistocene humans to modern-day humans.

3) The species of bacteria that thrive on starchy foods were virtually absent from the oral microbiomes of our most closely related primates – chimpanzees and gorillas.

The authors concluded, “This … supports an early importance of starch-rich foods in Homo evolution.”

In other words, our paleolithic ancestors likely did eat starchy foods. Their diet may not have contained grains, rice, or beans in significant quantities. However, they consumed whatever starchy roots, fruits, and vegetables they could find.

So, is the Paleo diet based on a myth? It depends on how you phrase the question.

  • If we ask whether our paleolithic ancestors consumed grains, rice, or beans, the answer is probably, “No”. The introduction of these foods in significant quantities probably depended on the agricultural revolution that occurred thousands of years later.
  • If we ask whether our paleolithic ancestors consumed starchy foods, the answer is probably, “Yes”. The foundation of the Paleo diet was based on a myth. Their oral microbiome contained bacterial species that thrived on starchy foods. In fact, starchy foods may have been an important staple in their diet because they are more calorie dense than other fruits and vegetables.
  • If we ask whether our paleolithic ancestors were capable of thriving on a diet that included grains, rice, and beans, the answer is also probably, “Yes”. The oral bacterial species that thrive on starchy foods do so by utilizing the alpha-amylase in human saliva. This means our paleolithic ancestors likely had enough alpha-amylase in their saliva to digest and to thrive on starchy foods like grains, rice, and beans.

Are Starchy Foods Bad For Us?

Starchy FoodsIt is not just the Paleo diet. Many popular diets have villainized starchy foods. Are starchy foods as bad for us as some “experts” would have you believe?

Let’s start by identifying starchy foods. If we think in terms of whole foods, they are:

  • Root vegetables (for example, potatoes, sweet potatoes, beets, carrots, and parsnips).
  • Legumes (for example, beans, peas, and lentils).
  • Grains (for example, wheat, rye, barley, oats, and rice).
  • Winter squash (for example, acorn squash, butternut squash, hubbard squash, and pumpkin).
  • Corn

These foods are good sources of nutrients and phytonutrients. Many of them are also excellent sources of fiber, including a special type of fiber called resistant starch. (I have described the benefits of resistant starch in a previous issue of “Health Tips From the Professor”.) These are foods that definitely deserve to be part of a healthy diet.

The only drawback of starchy vegetables is that they tend to be more calorie dense than other vegetables. While this was a “plus” for our paleolithic ancestors, it is not quite as advantageous in our modern world. If you are trying to watch your calories, my advice is to incorporate these foods into your diet sparingly.

However, there is another class of starchy foods you want to avoid. Of course, I am talking about highly processed foods made from grains, legumes, and corn. They retain all the calories but lose most of the nutrients, phytonutrients, and fiber of the foods they came from.

In short, starchy whole foods are a valuable part of a healthy diet. It is the starchy processed foods made from these whole foods you want to avoid. Of course, I am talking about bread, pasta, and pastries made from refined grains and sugar.

So, how do you know which starchy foods to avoid? My advice is not to become an expert label reader. Just eat foods without labels.

The Bottom Line

One of the founding principles on which the Paleo diet is based is that our paleolithic ancestors ate very few starchy foods, and the human body really isn’t designed to handle these foods. Accordingly, the Paleo diet recommends we should avoid starchy foods like grains and legumes. This has the unfortunate effect of creating an unbalanced diet that overemphasizes meat and animal fats.

But is this founding principle correct, or is it just a myth? When you look beneath the surface, you discover that it is a hypothesis based on the diets of the few primitive hunter-gatherer populations that still exist in our world.

It has been assumed that was as good an estimate of the paleolithic diet as we could get. After all there was no way to directly determine the starch content of the paleolithic diet – until now.

In this issue of “Health Tips From the Professor” I describe a novel approach that allowed scientists to determine the species of bacteria residing in the mouth of our humanoid ancestors based on the DNA extracted from the plaque coating their teeth. (For details on how this was done, read the article above.)

What the scientists found was that all human species, including a Neanderthal who died 100,000 years ago, harbored bacteria in their mouths that thrive on starchy foods.

The scientists concluded, “This … supports an early importance of starch-rich foods in Homo evolution.” In other words, our paleolithic ancestors likely did eat starchy foods. Restricting whole grains and legumes from the Paleo diet is based on a myth. They are an important part of a healthy diet.

For more details about the study and which starchy foods are bad 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.

What Do The US Dietary Guidelines Say About Supplementation?

What Do The US Dietary Guidelines Say About Your Diet?

Author: Dr. Stephen Chaney

US Dietary Guidelines 2020-2025Science is always changing, and nutritional science is no different. As we learn more, our concept of the “ideal diet” is constantly evolving. Because of that, the USDA and the US Department of Health & Human Services produce a new set of Dietary Guidelines for Americans every 5 years.

The 2020-2025 Dietary Guidelines for Americans have just been released. As usual, the process started with a panel of 20 internationally recognized scientists who produced a comprehensive report on the current state of nutritional science and made recommendations for updated dietary guidelines. After a period of public comment, the dietary guidelines were published.

There were two new features of the 2020-2025 Guidelines:

  • They provided dietary guidelines for every life stage from 6 months of life to adults over 60.
  • The guidelines also addressed personal preferences, cultural traditions, and budgetary concerns in so that each of us can develop a healthy diet that fits our lifestyle.

What Do The US Dietary Guidelines Say About Your Diet?

Here are the 2020-2025 Guidelines in a nutshell:healthy foods

  • Follow a healthy dietary pattern at every life stage.
  • Customize and enjoy nutrient-dense food and beverage choices to reflect personal preferences, cultural traditions, and budgetary considerations.
  • Focus on meeting food group needs with nutrient-dense foods and beverages and stay within calorie limits. They went on to say, “A healthy dietary pattern consists of nutrient-dense forms of foods and beverages across all food groups [emphasis mine], in recommended amounts, and within calorie limits.”

They said, “the core elements that make up a healthy dietary pattern include:”

    • Vegetables of all types – dark green, red, and orange vegetables; beans, peas, and lentils; starchy vegetables; and other vegetables.
    • Fruits – especially whole fruits.
    • Grains – at least half of which are whole.
    • Dairy – including fat-free or low-fat milk, yogurt, and cheese; lactose-free versions; and fortified soy beverages and soy yogurt as alternatives. [Other plant-based milk and yogurt foods were not recommended because they do not provide as much protein as dairy. So, they were not considered equivalent foods.]
    • Protein foods – including lean meats, poultry, and eggs; seafood; beans, peas, and lentils; and nuts, seeds, and soy products.
    • Oils – including vegetable oils and oils in food, such as seafood and nuts.
  • Limit foods and beverages higher in added sugars, saturated fat, and sodium; and limit No Fast Foodalcoholic beverages. Their specific recommendations are:
    • Added sugars – less than 10% of calories/day starting at age 2. Avoid foods and beverages with added sugars for those younger than 2.
    • Saturated fat – Less than 10% of calories starting at age 2.
    • Sodium – Less than 2,300 mg per day – even less for children younger than 14.
    • Alcoholic beverages – Adults of legal drinking age can choose not to drink, or to drink in moderation by limiting intake to 2 drinks or less in a day for men and 1 drink or less in a day for women, when alcohol is consumed. Drinking less is better for health than drinking more. There are some adults who should not drink alcohol, such as women who are pregnant.

For more details, read the 2020-2025 Dietary Guidelines for Americans.

The Dark Side Of The US Dietary Guidelines

Darth VaderThe US Dietary Guidelines point Americans in the right direction, but they are never as strong as most nutrition experts would like. The 2025 Dietary Guidelines are no exception. They have two major limitations:

#1: The food industry has watered down the guidelines. This happens every time a new set of guidelines are released. The food and beverage lobbies provide their input during the public comment period. And because they fund a significant portion of USDA research, their input carries a lot of weight. Here are the 3 places where they altered the recommendations of the scientific panel:

  • The scientific panel recommended that Americans decrease the intake of added sugar from 13% of daily calories to 6%. The final dietary guidelines recommended reducing sugar to 10% of daily calories.
  • The scientific panel recommended that both men and women limit alcoholic drinks to one a day. The final dietary guidelines recommended men limit alcoholic drinks to two a day.
  • The scientific panel included these statements in their report:
    • “Dietary patterns characterized by higher intake of red and processed meats, sugar-sweetened foods and beverages, and refined grains are…associated with detrimental health outcomes.”
    • “Replacing processed or high fat-meats…with seafood could help lower intake of saturated fat and sodium, nutrients that are often consumed in excess of recommended limits.”
    • “Replacing processed or high-fat meats with beans, peas, and lentils would have similar benefits.”

These statements are included in the final report, but they are buried in portions of the report that most people are unlikely to read. The summary that most people will read recommends shifts in protein consumption to “add variety” to the diet.

#2: The guidelines do not address sustainability and do not explicitly promote a shift to more Planetary Dietplant-based diets. Again, this was based on input from food lobby groups who argued that sustainability has nothing to do with nutrition.

If you are concerned about climate change and the degradation of our environment caused by our current farming practices, this is a significant omission.

I have covered this topic in a recent issue of “Health Tips From the Professor”. Here is a brief summary:

  • In 2019 a panel of international scientists was asked to conduct a comprehensive study on our diet and its effect on both our health and our environment.
  • The scientific panel carefully evaluated diet and food production methods and asked three questions:
    • Are they good for us?
    • Are they good for the planet?
    • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.
  • They developed dietary recommendations popularly known as the “Planetary Diet”. Here are the characteristics of the planetary diet.
    • It starts with a vegetarian diet. Vegetables, fruits, beans, nuts, soy foods, and whole grains are the foundation of the diet.
    • It allows the option of adding one serving of dairy a day.
    • It allows the option of adding one 3 oz serving of fish or poultry or one egg per day.
    • It allows the option of swapping seafood, poultry, or egg for a 3 oz serving of red meat no more than once a week. If you want a 12 oz steak, that would be no more than once a month.

Unless you are a vegan, this diet is much more restrictive than you are used to. However, if you, like so many Americans believe that climate change is an existential threat, I would draw your attention to one of the concluding statements from the panel’s report.

  • “Reaching the Paris Agreement of limiting global warming…is not possible by only decarbonizing the global energy systems. Transformation to healthy diets from sustainable food systems is essential to achieving the Paris Agreement.”

In other words, we can do everything else right, but if we fail to change our diet, we cannot avoid catastrophic global warming.

What Do The US Dietary Guidelines Say About Supplementation?

MultivitaminsThe authors of the 2020-2025 US Dietary Guidelines have relatively little to say about supplementation. However:

  • They list nutrients that are of “public health concern” for each age group. Nutrients of public health concern are nutrients that:
    • Are underconsumed in the American diet.
    • Are associated with health concerns when their intake is low.
  • They state that “dietary supplements may be useful in providing one or more nutrients that otherwise might be consumed in less than recommended amounts.”
  • They recommend specific supplements for several age groups.

Here are their nutrients of public health concern and recommended supplements for each age group:

#1: General population.

  • Nutrients of public health concern are calcium, dietary fiber, and vitamin D. They state that supplementation may be useful for meeting these needs.

#2: Breast Fed Infants.

  • Supplementation with 400 IU/day of vitamin D is recommended shortly after birth.

#3: Vegetarian Toddlers.

  • Iron and vitamin B12 are nutrients of concern.

#4: Children & Adolescents.

  • Calcium and vitamin D are nutrients of concern. Dairy and/or fortified soy alternatives are recommended to help meet these needs.
  • Iron, folate, vitamin B6, vitamin B12, and magnesium are also nutrients of concern for adolescent females.

#5: Adults (Ages 19-59).

  • 30% of men and 60% of women do not consume enough calcium and 90% of both men and women do not get enough vitamin D.

#6: Pregnant & Lactating Women:

  • Calcium, vitamin D, and fiber are nutrients of concern for all women in this age group.
  • In addition, women who are pregnant have special needs for folate/folic acid, iron, iodine, and vitamin D.
  • Women who are pregnant or thinking of becoming pregnant should take a daily prenatal vitamin and mineral supplement to meet folate/folic acid, iron, iodine, and vitamin D needs during pregnancy. They go on to say that many prenatal supplements do not contain iodine, so it is important to read the label.
  • All women who are planning or capable of pregnancy should take a daily supplement containing 400 to 800 mcg of folic acid.

#7: Older Adults (≥ 60).

  • Nutrients of concern for this age group include calcium, vitamin D, fiber, protein, and vitamin B12.
  • About 50% of women and 30% of men in this age group do not get enough protein in their diet.

My Perspective:

The US Dietary Guidelines use foods of public health concern as the only basis for recommending Supplementation Perspectivesupplementation. I prefer a more holistic approach that includes increased needs, genetic predisposition, and preexisting diseases as part of the equation (see the diagram on the right). I have discussed this concept in depth in a previous issue of “Health Tips From The Professor”.

I have also taken this concept and made supplement recommendations for various health goals in a free eBook called “Your Design For Healthy Living”.

Some people may feel I should have included more supplements in my recommendations. Others may feel I should have included fewer supplements in my recommendations. No list pf recommend supplements is perfect, but I have tried to include those supplements supported by good scientific evidence in my recommendations.

The Bottom Line 

The USDA and Department of Health & Human Services have just released the 2020-2025 US Dietary Guideline. In the article above I have summarized:

  • Their recommendations for a healthy diet.
  • Their recommendations for supplementation.
  • The dark side of the US Dietary Guidelines.

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.

Does Eating Plant Protein Help You Live Longer?

Are Whole Grains Heart Healthy?

protein and heart disease nuts and seedsThe diet wars continue. Dr. Strangelove and his colleagues are still trying to convince you that you can eat all the red meat you want. It is those deadly whole grains, beans, and fruits you need to avoid.

However, as the benefits of primarily plant-based diets continue to accumulate, it is becoming harder for them to maintain these preposterous claims.

For example, several recent studies have shown that replacing animal protein with plant protein in your diet results in better health.

  • The Iowa Women’s Health Study found that plant protein substitution for animal protein is associated with reduced risk of dying from heart disease.
  • The Nurse’s Health Study and Health Professionals Follow-up Study found that greater plant protein intake was associated with reduced risk of dying from heart disease and reduced risk of dying from all causes.
  • The Japan Public Health Center-Based Prospective Cohort Study found a reduced risk of dying from heart disease, cancer, and all causes with substitution of plant protein for red meat protein.

These were all very large studies in which populations were followed for long periods of time. You might be thinking that with such overwhelming evidence no further studies are needed.

However, these studies did not examine which plant protein sources were most beneficial and which animal protein sources were most detrimental. The study (J. Huang et al, JAMA Internal Medicine, published online July 13, 2020) I describe in today’s “Health Tips From The Professor” was designed to answer that question.

How Was The Study Done?

Clinical Study416,104 participants from the NIH-AARP Diet and Health Study were enrolled in this study in 1995 and 1996 and were followed for 16 years. At the time of enrollment, the participants filled out a comprehensive Diet History Questionnaire. The participants also completed questionnaires about their health, lifestyle, and socio-economic status.

Deaths were obtained from the Social Security Death Master File. Causes of death were obtained from the National Death Index Plus.

The basic characteristics of the study population were:

  • Gender: 57% men, 43% women.
  • Racial identification: 90% non-Hispanic white.
  • Average age 61 (range 50-71).
  • Average BMI = 27 (in the overweight range).
  • Participants were excluded from the study if they had pre-existing cancer, heart disease, stroke, or end-stage kidney disease.

In terms of protein intake:

  • Average protein intake was 15.3% of calories.
  • Plant protein contributed 40% (range 27% – 57%) to the total protein intake.
  • Animal protein contributed 60% (range = 43% to 63%) of the total protein intake.

The major sources of animal protein in the diet were:

  • Dairy products = 31.6%
  • White meat (poultry, fish, and processed white meat) = 31.3%
  • Red meat (both fresh and processed) = 30.6%
  • Eggs = 4.0%

The major sources of plant protein in the diet were:

  • Grains (bread, cereal, and pasta) = 45.8%
  • Beans and legumes = 8.0%
  • Nuts and seeds = 4.5%
  • Other plant protein (including plant protein from supplements) = 41.7%

All these protein intake figures are normal for the American diet.

I should note that beans, nuts, and seeds are among the best sources of plant protein. However, they are only a minor part of the typical American diet, so they contribute relatively little to our plant protein intake.

Does Eating Plant Protein Help You Live Longer?

In terms of overall protein intake, this study mirrored previous studies.

  • There was an inverse association between plant protein intake and premature death from heart disease, stroke, and all causes. Put another way, the more plant protein people in this study ate, the lower was their risk of premature death.

To quantify the effect, the investigators asked what happened when 3% of calories came from plant protein instead of animal protein. I recognize, however, that 3% of calories is a rather abstract concept, so let me break it down for you so you can apply it to your lives.

  • For participants in this study, protein was 15% of their total calories. That means when the investigators were talking about shifting 3% of total calories from animal protein to plant protein, they were talking about 20% of the protein in the diet coming from plant protein rather animal protein.
  • Based on the average caloric intake of participants in this study, that corresponds to 15 grams of protein for men and 12 grams of protein for women.

With that in mind, let’s look at the results:

  • Changing just 3% of calories from animal protein to plant protein:
  • Lowered the risk of premature death from all causes by 10% for both men and women.
  • Lowered the risk of premature death from cardiovascular disease by 11% for men and 12% for women.
  • Lowered the risk of premature death from stroke by 22% for men and 19% for women.

These findings are consistent with previous studies. By now, it should be apparent that primarily plant-based diets are best for your overall health. Primarily plant-based diets also appear to reduce your risk of dying prematurely from heart disease and from all other diseases combined.

The authors concluded: “This large cohort investigation showed small but significant associations between higher intake of plant protein and lower overall and cardiovascular mortality…Findings from this and previous studies provide evidence that dietary modifications in choice of protein sources may promote health and longevity.”

However, this part of the study merely confirms what other studies have shown. What makes this study unique is that it identifies which animal proteins are worst for us and which plant proteins are best for us.

Which Animal Proteins Are Least Heart Healthy?

Animal Protein FoodsLet’s start with the animal proteins (Note: To simplify a complex set of data, I am going to average the results for men and women).

  • Changing 3% of calories from egg protein to plant protein:
    • Lowered the risk of premature death from all causes by 23%.
    • Lowered the risk of premature death from cardiovascular disease by 27%.
    • To put this into perspective, 3% of calories from egg protein corresponds to around 2.5 eggs/day. So, talking about replacing 3% of calories of egg protein creates a false narrative. The average egg consumption in this study was 0.5 eggs/day and very few participants consumed even 2 eggs every day. If we make a more reasonable comparison, replacing one egg/day with an equivalent amount of plant protein:
      • Lowers the risk of premature death from all causes by 9%.
      • Lowers the risk of premature death from cardiovascular disease by 11%.
  • Changing 3% of calories from red meat protein to plant protein:
    • Lowered the risk of premature death from all causes by 14%.
    • Lowered the risk of premature death from cardiovascular disease by 12%.
    • Lowered the risk of premature death from stroke by 21%.
    • To put this into perspective, 3% of calories from red meat protein corresponds to around 2 ounces/day.
  • Changing 3% of calories from dairy protein to plant protein:
    • Lowered the risk of premature death from all causes by 8%.
    • Lowered the risk of premature death from cardiovascular disease by 11%.
    • Lowered the risk of premature death from stroke by 21%.
    • To put this into perspective, 3% of calories from dairy protein corresponds to around 1.7 8-ounce glasses of milk, 2 ounces of cheese, or 1 cup of yogurt (most yogurt “cups” sold commercially are less than an 8-ounce cup).
  • Changing 3% of calories from white meat protein to plant protein had no effect on premature death from any disease in this study. I will discuss the reasons for that below.

Are Whole Grains Heart Healthy?

Whole GrainsNow, let’s look at the flip side. What happens when you replace 3% of calories from red meat protein with various kinds of plant protein?

  • Changing 3% of calories from red meat protein to plant protein from whole grains:
    • Lowered the risk of premature death from all causes by 28%.
    • Lowered the risk of premature death from cardiovascular disease by 32%.
    • Lowered the risk of premature death from stroke by 32%.
    • To put this into perspective, 3% of calories from whole grain protein corresponds to around 2.5 slices of whole grain bread, 2 cups of oatmeal, or 2.5 cups of brown rice or whole grain pasta – or any combination of them during the day.
  • The results were similar for replacing egg protein with whole grain protein.
  • Changing 3% of calories from red meat protein or egg protein to other types of plant protein had no effect on premature death from any disease. The reasons for that will be discussed below.

The authors concluded “…this investigation showed prominent inverse associations between overall and cardiovascular mortality and the replacement of egg protein and red meat protein with plant protein, particularly for plant protein derived from bread, cereal, and pasta…”

Why Do Animal Proteins Increase Your Risk Of Premature Death?

Let me take a deep dive into the data. If you like, you can skip to “What Does This Study Mean For You?”

To help you gain a better understanding of these results, I will answer two questions for you:

  • Mechanism: What is/are the metabolic explanation(s) for these results?
  • Perspective: How can you apply this information to your own life?

Reminder: This section is for those of you who want the details. I will give the Cliff Notes summary in the section “What Does This Study Mean For You”.

EggsEggs

Mechanism:

  • The bad effect of eggs on cardiovascular mortality and all-cause mortality is thought to be almost exclusively due to their high cholesterol content.
  • On the flip side, eggs are an excellent source of low-fat animal protein and provide nutrients like choline and carotenoids that are often insufficient in the American diet.

Perspective:

  • Our bodies have a beautifully designed system for regulating blood cholesterol levels. This means under ideal conditions dietary cholesterol has very little effect on blood cholesterol levels. However, as I have pointed out in a previous issue of “Health Tips From the Professor”, conditions are often far from ideal.
  • Diet context matters. Obesity, saturated fat, and sugar all interfere with our ability to regulate blood cholesterol levels. People consuming the typical American diet, like the ones in this study, have more difficulty regulating their blood cholesterol levels and are more likely to be adversely affected by dietary cholesterol from eggs and other high-cholesterol foods.
    • Previous studies suggest that adding eggs to the typical American diet may increase risk of cardiovascular disease and premature death.
    • In contrast, adding eggs to a primarily plant-based diet, such as found in China and Japan, appears to decrease risk of heart disease and premature death.

Red Meatfatty steak

Mechanisms: The mechanism(s) associated with the bad effects of red meat are less clear. Here are the potential mechanisms discussed by the authors of this study.

  • Red meat is high in cholesterol. While many experts have downplayed the importance of dietary cholesterol in recent years, it still may be of concern in the context of the typical American diet because of our body’s inability to regulate cholesterol metabolism normally.
  • Red meat is high in saturated fat. While some experts have downplayed the importance of reducing saturated fat intake, I pointed out in a previous issue of “Health Tips From the Professor” that it depends on what the saturated fat is replaced with.
    • When saturated fats are replaced with sugar and refined carbohydrates in the typical American diet, reducing saturated fat is of no benefit.
    • When saturated fats are replaced with polyunsaturated fats in the context of a primarily plant-based diet, such as the Mediterranean diet, reducing saturated fats leads to a substantial reduction in the risk of heart disease and premature death.
  • Red meat also contains heme iron which is associated with 57% increased risk of cardiovascular disease.
  • Diets high in red meat result in populations of gut bacteria that are associated with increased risk of cardiovascular disease. This is most likely because red meat is displacing plant foods that support the growth of healthy bacteria.
  • As discussed in a recent issue of “Health Tips From the Professor”, the gut bacteria associated with red meat consumption convert the L-carnitine in red meat to a metabolite called trimethylamine N-oxide (TMAO) which appears to significantly increase the risk of cardiovascular disease.
  • Finally, a recent study suggests that foods high in sulfur-containing amino acids significantly increase risk of cardiovascular disease. However, this mechanism is not specific for red meat. White meat, beans, and legumes are also high in sulfur-containing amino acids.

Perspective:

  • While the exact mechanism(s) is/are uncertain, there is substantial evidence from multiple studies that red meat consumption increases the risk of premature death from cardiovascular disease and from all causes.
  • Grass fed beef is not a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • However, those of you who, like me, enjoy red meat should not consider this to be an absolute “red meat should never touch your lips” edict. As I have discussed in a previous issue of “Health Tips From the Professor”, the health effects of red meat are a matter of quantity and diet context.
    • If you are thinking in terms of a juicy 8-ounce steak with a baked potato and sour cream, red meat is probably not a healthy choice.
    • However, if you are thinking of 2-3 ounces of lean steak in a vegetable stir fry or a green salad, red meat may be a healthier choice.

dairy products and heart diseaseDairy: I have reported on the health risks and benefits of dairy foods in a previous issue of “Health Tips From the Professor”, so I will just give you a brief summary here.

Perspective:

  • Eating dairy foods, even high-fat dairy foods, has relatively little effect on cardiovascular disease risk in the context of the typical high-fat, high-sugar American diet.
  • Eating dairy foods, even high-fat dairy foods, in the context of a healthy plant-based diet appears to lower cardiovascular disease risk.
  • As this study suggests, moving towards a more plant-based diet by substituting some plant protein for dairy protein in the diet will also decrease your risk of cardiovascular disease

White Meat: This and previous studies suggest that white meat is less likely than red meat to increase the risk of cardiovascular disease and premature death. I have discussed the differences between red and white meat in a previous issue of “Health Tips From the Professor”. However, I can summarize the differences best here by going back to the mechanisms associated with the link between red meat and cardiovascular diseases and highlight those that do not apply to white meat.

Mechanisms:

  • Saturated fat. Many fish are much lower in saturated fat and are excellent sources of heart-healthy omega-3 fats. Chicken and turkey breast with the skin removed are also much lower in saturated fat than red meat.
  • Heme iron. Chicken breast is lower in heme iron than red meats.
  • TMAO. White meats contain 10-50 times less L-carnitine than red meats. Since L-carnitine is the precursor of TMAO, they are much less likely to cause TMAO production.

Why Do Plant Proteins Decrease Your Risk Of Premature Death?

Whole Grains: Whole grains have been much maligned in recent years. They have been lumped in with sugar and refined grains and have been added to everyone’s “naughty list”.

  • If you are following a low-carb diet, you are told to avoid all grains.
  • If you are following a Paleo diet, you are told our paleo ancestors ate no grains.
  • If you are trying to avoid lectins…you get the point.

That’s unfortunate, because whole grains are very healthy. In a recent issue of “Health Tips From the Professor” I shared a study showing that whole grain consumption reduced the risk of premature death from heart disease, cancer, and all causes. The current study shows essentially the same thing.

The only question is why whole grains are uniquely effective at decreasing premature death from cardiovascular disease and all causes in this study. Why aren’t all plant proteins equally effective? I will share both a suggested mechanism and perspective.

Mechanism:

  • In a recent issue of “Health Tips From The Professor” I reported a study showing that grains and a few other foods contain a unique type of fiber called resistant starch that suppress growth of the gut bacteria which convert L-carnitine to TMAO. This may be why whole grains are uniquely effective at reducing the risk of cardiovascular disease and premature death.
  • Some refined grains are also good sources of resistant starch. However, I don’t recommend them because they lack the antioxidants, vitamins, phytonutrients, and insoluble fiber found in whole grains.

Perspective:  

The fact no other plant protein source significantly reduced heart disease risk in this study is most likely an artifact of the study.

  • The study asked what happens when you change 15 grams of the protein in your diet from red meat protein to different kinds of plant protein. That question was easy to answer for grains because they are a major source of protein in the American diet. However, Americans don’t get enough protein from other high protein plant foods like beans and legumes or nuts and seeds to provide a statistically valid answer to that question.
  • However, all plant foods have their own health benefits. They are excellent sources of antioxidants and phytonutrients that provide heart health benefits.
  • In addition, each plant food provides a different blend of fibers and supports different populations of gut bacteria with different health benefits. For example, fiber from fruits and vegetables is associated with a lower risk of cancer.

What Does This Study Mean For You?

dairy products and heart disease questionsA recent study has shown that changing as little as 20% of the protein in our diet from animal protein to plant protein significantly reduces our risk of premature death from cardiovascular disease, stroke, and from all causes.

The effect of replacing 2 ounces of red meat, 1 egg, or 2 servings of dairy with an equivalent amount of plant protein was equally beneficial.

Previous studies show that diet context is important. A small amounts of animal protein in the context of a whole food, primarily plant-based diet is much less likely to cause harm and may provide benefit. For example:

  • Eggs are high in cholesterol but are also excellent sources of low-fat protein and nutrients that may be missing in a plant-based diet.
    • Previous studies suggest that adding eggs to the typical American diet may increase risk of cardiovascular disease and premature death.
    • In contrast, adding eggs to a primarily plant-based diet, such as found in China and Japan, appears to decrease risk of cardiovascular disease and premature death.
  • Dairy foods are high in saturated fat but are excellent sources of calcium, vitamin D, and other nutrients that may be missing in a plant-based diet.
    • Eating dairy foods, even high-fat dairy foods, has relatively little effect on cardiovascular disease risk in the context of the typical high-fat, high-sugar American diet.
    • Eating dairy foods, even high-fat dairy foods, in the context of a healthy plant-based diet appears to lower cardiovascular disease risk.
  • Red meat has multiple suggested mechanisms for it increasing the risk of death from cardiovascular disease. However, diet context still matters.
    • If you are thinking in terms of a juicy 8-ounce steak with a baked potato and sour cream, red meat is probably not a healthy choice.
    • However, if you are thinking of 2-3 ounces of lean steak in a vegetable stir fry or a green salad, red meat may be a healthier choice.
    • Grass fed beef should not be considered a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • White meat does not appear to affect your risk of developing cardiovascular disease.
  • Whole grains significantly decreased the risk of premature death from cardiovascular disease and death from all causes. This may be because whole grains contain a unique type of fiber called resistant starch that suppresses the growth of the gut bacteria which convert L-carnitine to a heart-damaging compound called TMAO.
    • Notice that I specified “whole grain”. While some refined grains are also a good source of resistant starch, they lack the other heart healthy nutrients and phytonutrients found in whole grains.
      • Wonder Bread, Frosted Flakes, Honey Bunches of Oats, and white-flour pasta are not on my approved list. I agree with low-carb enthusiasts about eliminating them from our diets.
      • You should also be aware that “whole grain” on the label means nothing. You want to choose foods that say “100% whole grain”.
    • Finally, this study only focused on plant protein sources. It is important to remember that other plant foods are an excellent source of antioxidants, phytonutrients, and fiber. Each plant food provides unique heart health benefits.

The Bottom Line

A recent study has shown that changing as little as 20% of the protein in our diet from animal protein to plant protein significantly reduces our risk of premature death from cardiovascular disease, stroke, and from all causes.

The effect of replacing 2 ounces of red meat, 1 egg, or 2 servings of dairy with an equivalent amount of plant protein was equally beneficial. White meat did not affect the risk of cardiovascular disease or premature death.

  • Grass fed beef should not be considered a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • Diet context is important. Small amounts of animal protein in the context of a whole food, primarily plant-based diet appear to be much healthier for us than large amounts of animal protein in the context of the high-fat, high-sugar American diet.

On the flip side of the equation, whole grains significantly decreased the risk of premature death from cardiovascular disease and death from all causes. This has also been seen in other recent studies.

  • Notice that I specified “whole grain”. Wonder Bread, Frosted Flakes, Honey Bunches of Oats, and white-flour pasta are not on the list.
  • You should also be aware that “whole grain” on the label means nothing. You want to choose foods that say “100% whole grain”.
  • Finally, this study only focused on plant protein sources. It is important to remember that other plant foods are an excellent source of antioxidants, phytonutrients, and fiber. Each plant food provides unique heart health benefits.

For more details, read the article above, especially the “What Does This Study Mean For You?” section.

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.

Should I Avoid Whole Grains?

Will Whole Grains Kill Me?

Whole GrainsIt seems like just yesterday that health experts all agreed that whole grains were good for us. After all:

  • They are a good source of fiber, B vitamins, vitamin E, and the minerals magnesium, iron, zinc, manganese, and selenium.
  • Their fiber fills you up, so you are less likely to overeat. This helps with weight control.
  • Their fiber also supports the growth of friendly bacteria in your gut.

In fact, the USDA still recommends that half of the grains we eat should be whole grains. And, outside experts, not influenced by the food industry, feel this recommendation is too low. They feel most of the grains we eat should be whole grains. Foods made from refined grains should be considered as only occasional treats.

Then the low-carb craze came along. Diets like Paleo and Keto were telling you to avoid all grains, even whole grains. Even worse, Dr. Strangelove and his colleagues were telling you whole grains contained something called lectins that were bad for you. Suddenly, whole grains went from being heroes to being villains.

You are probably asking, “Should I avoid whole grains?” What is the truth? Perhaps the best way to resolve this debate is to ask, how healthy are people who consume whole grains for many years? This week I share a recent study (G Zong et al, Circulation, 133: 2370-2380, 2016) that answers that very question.

How Was The Study Done?

This study was a meta-analysis of 14 clinical trials that:

  • Enrolled a total of 786,076 participants.
  • Obtained a detailed diet history at baseline.
  • Followed the participants for an average of 15 years (range = 6-28 years).
  • Determined the effect of whole grain consumption on the risk of death from heart disease, cancer, and all causes.

Will Whole Grains Kill Me?

deadDr. Strangelove and his colleagues are claiming that whole grains cause inflammation, which increases your risk of heart disease and cancer. Heart disease and cancer are the leading causes of death in this country. In fact, according to the CDC, heart disease and cancer accounted for 44% of all deaths in the US in 2017.

Therefore, if Dr. Strangelove and his colleagues were correct, consumption of whole grains should increase the risk of deaths due to heart disease and cancer – and increase the risk of death due to all causes.

That is not what this study showed.

When the highest whole grain intake (5 servings/day) was compared with the lowest whole grain intake (0 servings/day), whole grain consumption reduced the risk of death from:

  • Heart disease by 18%.
  • Cancer by 12%.
  • All causes by 16%.

Furthermore, the effect of whole grains on mortality showed an inverse dose response. Simply put, the more thumbs upwhole grains people consumed, the lower the risk of deaths from heart disease, cancer, and all causes.

However, the dose response was not linear. Simply going from 0 servings of whole grains to one serving of whole grains reduced the risk of death from.

  • Heart disease by 9%.
  • Cancer by 5%.
  • All causes by 7%.

The authors concluded: “Whole grain consumption was inversely associated with mortality in a dose-response manner, and the association with cardiovascular mortality was particularly strong and robust. These observations endorse current dietary guidelines that recommend increasing whole grain intake to replace refined grains to facilitate long-term health and to help prevent premature death.”

The authors went on to say: “Low-carbohydrate diets that ignore the health benefits of whole grain foods should be adopted with caution because they have been linked to higher cardiovascular risk and mortality.”

Should I Avoid Whole Grains?

Question MarkAs for the original question, “Should I avoid whole grains?”, the answer appears to be a clear, “No”.

The strengths of this study include the large number of participants (786,076) and the demonstration of a clear dose-response relationship between whole grain intake and reduced mortality.

This study is also consistent with several other studies that show whole grain consumption is associated with a lower risk of heart disease, diabetes, cancer – and appears to lead to a longer, healthier life.

In short, it appears that Dr. Strangelove and the low-carb enthusiasts are wrong. Whole grains aren’t something to avoid. They reduce the risk of heart disease, diabetes, and cancer. And they reduce the risk of premature death. We should be eating more whole grains, not less.

However, the authors did point out that this study has some weaknesses:

  • It is an association study, which does not prove cause and effect.
  • Study participants who consumed more whole grains also tended to consume more fruits and vegetables – and less red meat, sodas, and highly processed foods.

However, I would argue the second point is a strength, not a weakness. We need to give up the idea that certain foods or food groups are “heroes” or “villains”. We know that primarily plant-based diets like the Mediterranean and DASH diets are incredibly healthy. Does it really matter how much of those health benefits come from whole grains and how much comes from fruits and vegetables?

The Bottom Line

Dr. Strangelove and low-carb enthusiasts have been telling us we should avoid all grains, including whole grains. Is that good advice?

If Dr. Strangelove and his colleagues were correct, consumption of whole grains should increase the risk of deaths due to the top two killer diseases, heart disease and cancer. Furthermore, because heart disease and cancer account for 44% of all deaths in this country, whole grain consumption should also increase the risk of death due to all causes.

A recent study showed the exact opposite. The study showed:

When the highest whole grain intake (5 servings/day) was compared with the lowest whole grain intake (0 servings/day), whole grain consumption reduced the risk of death from:

  • Heart disease by 18%.
  • Cancer by 12%.
  • All causes by 16%.

Furthermore, the effect of whole grains on mortality showed an inverse dose response. Simply put, the more whole grains people consumed, the lower the risk of deaths from heart disease, cancer, and all causes.

However, the dose response was not linear. Simply going from 0 servings of whole grains to one serving of whole grains reduced the risk of death from.

  • Heart disease by 9%.
  • Cancer by 5%.
  • All causes by 7%.

The authors concluded: “Whole grain consumption was inversely associated with mortality in a dose-response manner, and the association with cardiovascular mortality was particularly strong and robust. These observations endorse current dietary guidelines that recommend increasing whole grain intake to replace refined grains to facilitate long-term health and to help prevent premature death.”

The authors went on to say: “Low-carbohydrate diets that ignore the health benefits of whole grain foods should be adopted with caution because they have been linked to higher cardiovascular risk and mortality.”

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.

Can You Improve Your Healthspan?

Can You Live Healthier, Longer?

Ever since Ponce de Leon led an expedition to the Florida coast in 1513, we have been searching for the mythical “Fountain Of Youth”. What does that myth mean?

Supposedly, just by immersing yourself in that fountain you would be made younger. You would experience all the exuberance and health you enjoyed when you were young. There have been many snake oil remedies over the years that have promised that. They were all frauds.

But what if you had it in your power to live longer and to retain your youthful health for most of those extra years. The ability to live healthier longer is something that scientists call “healthspan”. But you can think of it as your personal “Fountain Of Youth”.

Where are we as a nation? Americans ranked 53rd in the world for life expectancy. We have the life expectancy of a third-world country. We are in sore need of a “Fountain Of Youth”.

That is why I decided to share two recent studies from the prestigious Harvard T.H. Chan School of Public Health with you today.

How Were The Studies Done?

Clinical StudyThese studies started by combining the data from two major clinical trials:

  • The Nurse’s Health Study, which ran from 1980 to 2014.
  • The Health Professional’s Follow-Up Study, which ran from 1986-2014.

These two clinical trials enrolled 78,865 women and 42,354 men and followed them for an average of 34 years. During this time there were 42,167 deaths. All the participants were free of heart disease, type 2 diabetes, and cancer at the time they were enrolled. Furthermore, the design of these clinical trials was extraordinary.

  • A detailed food frequency questionnaire was administered every 2-4 years. This allowed the investigators to calculate cumulative averages of all dietary variables.
  • Participants also filled out questionnaires that captured information on disease diagnosis every 2 years with follow-up rates >90%. This allowed the investigators to measure the onset of disease for each participant during the study. More importantly, 34 years is long enough to measure the onset of diseases like heart disease, diabetes, and cancer – diseases that require decades to develop.
  • The questionnaires also captured information on medicines taken and lifestyle characteristics such as body weight, exercise, smoking and alcohol use.
  • For analysis of diet quality, the investigators use something called the “Alternative Healthy Eating Index”. [The original Healthy Eating Index was developed about 10 years ago based on the 2010 “Dietary Guidelines for Americans”. Those guidelines have since been updated, and the “Alternative Healthy Eating Index” is based on the updated guidelines.] You can calculate your own Alternative Healthy Eating Index below, so you can see what is involved.
  • Finally, the investigators included five lifestyle-related factors – diet, smoking, physical activity, alcohol consumption, and BMI (a measure of obesity) – in their estimation of a healthy lifestyle. Based on the best available evidence, they defined “low-risk” in each of these categories. Study participants were assigned 1 point for each low-risk category they achieved. Simply put, if they were low risk in all 5 categories, they received a score of 5. If they were low risk in none of the categories, they received a score of 0.
  • Low risk for each of these categories was defined as follows:
    • Low risk for a healthy diet was defined as those who scored in the top 40% in the Alternative Healthy Eating Index.
    • Low risk for smoking was defined as never smoking.
    • Low risk for physical activity was defined as 30 minutes/day of moderate or vigorous activities.
    • Low risk for alcohol was defined as 0.5-1 drinks/day for women and 0.5-2 drinks/day for men.
    • Low risk for weight was defined as a BMI in the healthy range (18.5-24.9 kg/m2).

Can You Live Healthier Longer?

Older Couple Running Along BeachThe investigators compared participants who scored as low risk in all 5 categories with participants who scored as low risk in 0 categories (which would be typical for many Americans). For the purpose of simplicity, I will refer to people who scored as low risk in 5 categories as having a “healthy lifestyle” and those who scored as low risk in 0 categories as having an “unhealthy lifestyle”.

The results of the first study were:

  • Women who had had a healthy lifestyle lived 14 years longer than women with an unhealthy lifestyle (estimated life expectancy of 93 versus 79).
  • Men who had a healthy lifestyle lived 12 years longer than men with an unhealthy lifestyle (estimated life expectancy was 87 versus 75).
  • It was not necessary to achieve a perfect lifestyle. Life expectancy increased in a linear fashion for each low-risk lifestyle behavior achieved.

The authors of the study concluded: “Adopting a healthy lifestyle could substantially reduce premature mortality and prolong life expectancy in US adults. Our findings suggest that the gap in life expectancy between the US and other developed countries could be narrowed by improving lifestyle factors.”

The results of the second study were:

  • Women who had a healthy lifestyle lived 11 years longer free of diabetes, heart disease, and cancer than women who had an unhealthy lifestyle (estimated disease-free life expectancy of 85 years versus 74 years).
  • Men who had a healthy lifestyle lived 8 years longer free of diabetes, heart disease, and cancer than men who had an unhealthy lifestyle (estimated disease-free life expectancy of 81 years versus 73 years).
  • Again, disease-free life expectancy increased in a linear fashion for each low-risk lifestyle behavior achieved.

The authors concluded: “Adherence to a healthy lifestyle at mid-life [They started their analysis at age 50] is associated with a longer life expectancy free of major chronic diseases. Our findings suggest that promotion of a healthy lifestyle would help reduce healthcare burdens through lowering the risk of developing multiple chronic diseases, including cancer, cardiovascular disease, and diabetes, and extending disease-free life expectancy.”

Can You Improve Your Healthspan?

Questioning ManI posed the question at the beginning of this article, “Can you improve your healthspan?” These two studies showed that you can improve both your life expectancy and your disease-free life expectancy. So, the answer to the original question appears to be, “Yes, you can improve your healthspan. You can create your personal “Fountain of Youth.”

However, as a nation we appear to be moving in the wrong direction. The percentage of US adults adhering to a healthy lifestyle has decreased from 15% in 1988-1992 to 8% in 2001-2006.

The clinical trials that these studies drew their data from were very well designed, so these are strong studies. However, like all scientific studies, they have some weaknesses, namely:

  • They looked at the association of a healthy lifestyle with life expectancy and disease-free life expectancy. Like all association studies, they cannot prove cause and effect.
  • The clinical trials they drew their data with included mostly Caucasian health professionals. The results may differ with different ethnic groups.
  • These studies did not look at the effect of a healthy lifestyle on the onset of Alzheimer’s disease and other forms of dementia. However, other studies have shown that people who were low risk for each of the 5 lifestyle factors (diet, exercise, body weight, smoking, and alcohol use) individually have a reduced risk of developing Alzheimer’s and/or dementia.

Finally, I know you have some questions, and I have answers.

Question: What about supplementation? Will it also improve my healthspan?

Answer: When the investigators analyzed the data, they found that those with the healthiest lifestyles were also more likely to be taking a multivitamin. So, they attempted to statistically eliminate any effect of supplement use on the outcomes. That means these studies cannot answer that question.

However, if you calculate your Alternate Healthy Eating Index below, you will see that most of us fall short of perfection. Supplementation can fill in the gaps.

Question: I cannot imagine myself reaching perfection in all 5 lifestyle categories? Should I even try to achieve low risk in one or two categories?

Answer: The good news is that there was a linear increase in both life expectancy and disease-free life expectancy as people went from low-risk in one category to low-risk in all 5 categories. I would encourage you to try and achieve low risk status in as many categories as possible, but very few of us, including me, achieve perfection in all 5 categories.

Question: I am past 50 already. Is it too late for me to improve my healthspan?

Answer: Diet and some of the other lifestyle behaviors were remarkably constant over 34 years in both the Nurse’s Health Study and the Health Professional’s Follow-Up Study. That means that the lifespan and healthspan benefits reported in these studies probably resulted from adhering to a healthy lifestyle for most of their adult years.

However, it is never too late to start improving your lifestyle. You may not achieve the full benefits described in these studies, but you still can add years and disease-free years to your life.

How To Calculate Your Alternative Healthy Eating Index

You can calculate your own Alternative Healthy Eating Index score by simply adding up the points you score for each food category below.

Vegetables

Count 2 points for each serving you eat per day (up to 5 servings).

One serving = 1 cup green leafy vegetables or ½ cup for all other vegetables.

Do not count white potatoes or processed vegetables like French fries or kale chips.

Fruits

Count 2½ points for each serving you eat per day (up to 4 servings).

One serving = 1 piece of fruit or ½ cup of berries.

          (do not count fruit juice or fruit incorporated into desserts or pastries). 

Whole Grains

Count 2 points for each serving you eat per day (up to 5 servings).

One serving = ½ cup whole-grain rice, bulgur and other whole grains, cereal, and pasta or 1 slice of bread.

(For processed foods like pasta and bread, the label must say 100% whole grain).

Sugary Drinks and Fruit Juice

Count 10 points if you drink 0 servings per week.

Count 5 points for 3-4 servings per week (½ serving per day).

Count 0 points for 7 or more servings per week (≥1 serving per day).

One serving = 8 oz. fruit juice, sugary soda, sweetened tea, coffee drink, energy drink, or sports drink.

Nuts, Seeds and Beans

Count 10 points if you eat 7 or more servings per week (≥1 serving per day).

Count 5 points for 3-4 servings per week (½ serving per day).

Count 0 points for 0 servings per week.

One serving = 1 oz. nuts or seeds, 1 Tbs. peanut butter, ½ cup beans, 3½ oz. tofu.

Red and Processed Meat

Count 10 points if you eat 0 servings per week.

Count 7 points for 3-4 servings per week (½ serving per day).

Count 3 points for 3 servings per week (1 serving per day).

Count 0 points for ≥1½ servings per day.

One serving = 1½ oz. processed meats (bacon, ham, sausage, hot dogs, deli meat)

          Or 4 oz. red meat (steak, hamburger, pork chops, lamb chops, etc.)

Seafood

Count 10 points if you eat 2 servings per week.

Count 5 points for 1 serving per week.

Count 0 points for 0 servings per week.

1 serving = 4 oz.

Now that you have your total, the scoring system is:

  • 41 or higher is excellent
  • 37-40 is good
  • 33-36 is average (remember that it is average to be sick in this country)
  • 28-32 is below average
  • Below 28 is poor

Finally, for the purposes of these two studies, a score of 37 or higher was considered low risk.

The Bottom Line

Two recent studies have developed a healthy lifestyle score based on diet, exercise, body weight, smoking, and alcohol use. When they compared the effect of lifestyle on both lifespan (life expectancy) and healthspan (disease-free life expectancy), they reported:

  • Women who had had a healthy lifestyle lived 14 years longer than women with an unhealthy lifestyle.
  • Men who had a healthy lifestyle lived 12 years longer than men with an unhealthy lifestyle.
  • Women who had a healthy lifestyle lived 11 years longer free of diabetes, heart disease, and cancer than women had an unhealthy lifestyle.
  • Men who had a healthy lifestyle lived 8 years longer free of diabetes, heart disease, and cancer than men who had an unhealthy lifestyle.
  • It is not necessary to achieve a perfect lifestyle. Lifespan and healthspan increased in a linear fashion for each low-risk lifestyle behavior (diet, exercise, body weight, smoking, and alcohol use) achieved.
  • These studies did not evaluate whether supplement use also affects healthspan.
    • However, if you calculate your diet with the Alternate Healthy Eating Index they use (see above), you will see that most of us fall short of perfection. Supplementation can fill in the gaps.

The authors concluded: “Our findings suggest that promotion of a healthy lifestyle would help reduce healthcare burdens through lowering the risk of developing multiple chronic diseases, including cancer, cardiovascular disease, and diabetes, and extending disease-free life expectancy.”

For more details, including how to calculate whether you are low risk in each of the 5 lifestyle categories, 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.

Diet And Cancer Risk

What Can You Do To Reduce Your Risk Of Cancer?

Magic WandIt seems like everyone has a magic pill, essential oil, food, or diet that prevents cancer. It doesn’t take a genius to figure out that all the claims can’t be true. No wonder you are confused. You want to know:

  • Which of these claims are true?
  • What can you do to reduce your risk of cancer?

These aren’t trivial questions.

  • Cancer is the second leading cause of death in this country, and some experts predict it will surpass heart disease as the leading cause of death in the near future.
  • While cancer treatments have become much more effective in the past few decades, these treatment successes are often associated with severe side-effects, enormous expense, or both.

That is why I was intrigued by a recent study (FF Zhang et al, JNCI Cancer Spectrum (2019) 3(2): pkz034) on diet and cancer that came from the prestigious Friedman School of Nutrition and Public Policy at Tufts University. This study asked two important questions:

  • How many newly diagnosed cancer cases could have been prevented by changes in the American diet? This is something the authors referred to as the “preventable cancer burden associated with poor diet”.
  • Which foods increased or decreased the risk of cancer? This, of course, is the most useful information for you and me.

Diet And Cancer Risk

Diet And CancerThis study estimated that 80,110 new cancer cases among US adults 20 and older could be primarily attributed to poor diet. While poor diet contributes to many more cancers, the authors of this study felt 80,110 represented the number of cancer cases that were clearly preventable by some simple dietary changes.

While all cancers were affected by diet to some degree, the cancers most affected by poor diet were:

  • Colon cancer (65% of cases)
  • Mouth and throat cancer (18% of cases)
  • Endometrial cancer (4.0% of cases)
  • Breast cancer (3.8% of cases)

When the diet was broken down into individual food groups:

  • Low intake of whole grains was associated with the largest number of preventable cancer cases (35% of cases). This was followed by.
  • Low intake of dairy foods (22% of cases).
  • High intake of processed meats (18% of cases).
  • Low intake of vegetables (16% of cases).
  • Low intake of fruits (10% of cases).
  • High intake of red meat (7.1% of cases).
  • High intake of sugar sweetened beverages (4.0% of cases).

Of the diet-associated cancer cases, the scientists who lead the study estimated that 84% of them represented a direct effect of diet on cancer risk. The dietary factors most likely to directly increase the risk of cancer were:

  • Low intake of whole grains.
  • Low intake of dairy foods.
  • High intake of processed meats.

The scientists estimated that 16% of diet-associated cancer cases were “mediated by obesity”. In layman’s terms, this means that diet increased the risk of obesity and obesity increased the risk of cancer. The dietary factors most likely to increase the risk of obesity-mediated cancers were:

  • High intake of sugar sweetened beverages.
  • Low intake of fruits.

The authors concluded: “More than 80,000 new cancer cases [per year] are estimated to be associated with suboptimal diet among US adults…Our findings underscore the need for reducing cancer burden in the United States by improving the intake of key food groups and nutrients of Americans.”

What Does This Mean For You?

Questioning ManThese findings aren’t novel. Many previous studies have come to the same conclusions. However, many people find these recommendations to be confusing. Should they increase their intake of certain foods? Should they follow some sort of magic diet?

Perhaps we need to get away from the magic food concept. We need to understand that every time we increase one food in our diet, we exclude other foods. We need to step back and look at the overall diet.

Let me break down the recommendations from this study into three categories: foods we should eliminate from our diet, foods we should include in our diet, and foods we should balance in our diet.

Foods we should eliminate from our diet:

  • Sugar Sweetened Beverages. They provide no nutritional benefit, and the sugar in most beverages rushes into our bloodstream and overwhelms our body’s ability to utilize it in a healthy way. This leads to obesity, diabetes, and a host of other health issues.
    • Public enemy number one is sodas. However, this category also includes fruit juices, sweetened teas and energy drinks, and sugary processed foods.
    • This category also includes diet sodas. For reasons we don’t completely understand, diet sodas appear to be just as likely to lead to obesity, diabetes, and heart disease as sugar sweetened sodas. I have discussed the proposed explanations of this phenomenon in a recent issue of “Health Tips From the Professor”.
    • Sugar, however, is not the enemy. Sugar found naturally in fruits and other whole foods enters the bloodstream slowly and is metabolized in healthy ways by the body. I have discussed this in another issue  of “Health Tips From the Professor”. This is what I mean by restoring balance in our diet. Decreasing the sugar intake from sugar sweetened beverages and increasing sugar intake from fruits is associated with a decreased risk of obesity and obesity-related cancers.
  • Processed Meats. The evidence is overwhelming at this point that processed meats directly increase the risk of cancer.
    • If you have trouble completely eliminating processed meats from your diet, my advice is to minimize them and consume them only in the context of an overall healthy diet. Personally, I still consume bacon occasionally as flavoring for a healthy green salad.

Whole GrainsFoods we should include in our diet. I put these in a separate category because Dr. Strangelove and his colleagues have been telling us to eliminate them from our diet, and many Americans are following those recommendations:

  • Whole grains. We can think of whole grains as the underserving victim of the low-carb craze. The low-carb craze is on the mark when it comes to eliminating added sugars and refined grains from the diet. However, eliminating whole grains from the diet may be doing more harm than good. In fact, this and other studies suggest that whole grains are the most effective foods for reducing cancer risk. Why is that?
    • If we assume whole grains are just a good source of fiber and a few vitamins and minerals, it is hard to grasp their importance. We could easily get those nutrients elsewhere.
    • However, we are beginning to realize that whole grains play a unique role in supporting certain species of gut bacteria that are very beneficial to our health. In short, whole grains may be essential for a healthy gut.
  • Dairy Foods. This is another food that has been treated as a villain by Dr. Strangelove and his many colleagues. However, for reasons we don’t completely understand, dairy foods appear to decrease the risk of heart disease and cancer.

Foods we should balance in our diet.

  • Red Meat. Diets high in red meat are consistently associated with a slight increase in cancer risk. The World Health Organization lists red meat as a probable carcinogen, but that has proven to be controversial.
    • Much of the research has centered on why red meat causes cancer. Several mechanisms have been proposed, but none of them have been proven.
    • In contrast, very little consideration has been given to what red meat is displacing from the diet. Diets high in red meat are often low in whole grains, fruits and/or vegetables.
    • Perhaps instead of eliminating red meat from our diets we should be talking about balancing red meat in our diets by consuming less red meat and more whole grains, fruits, and vegetables.

What Can You Do To Reduce Cancer Risk?

American Cancer SocietyYou may have been thinking that 80,110 cases/year represents a small percentage of new cancer cases. That’s because diet is only one component of a holistic cancer prevention strategy. Here is what the American Cancer Society recommends for reducing cancer risk:

  • Avoid tobacco.
  • Limit sun exposure.
  • Achieve and maintain a healthy weight.
  • Eat a healthy diet, with an emphasis on plant foods (Their recommendations are in line with this study).
  • Be physically active.
  • Limit alcohol use.
  • Get vaccinated against HPV.
  • Get regular medical checkups.

Doing any of these things will reduce your cancer risk. But the more of these you can incorporate into your lifestyle, the lower your risk.

The Bottom Line

A recent study looked at diet and cancer risk. The authors reported that 80,110 new cancer cases among US adults 20 and older could be primarily attributed to poor diet.

When the diet was broken down into individual food groups:

  • Low intake of whole grains was associated with the largest number of preventable cancer cases. This was followed in descending order by.
  • Low intake of dairy foods.
  • High intake of processed meats.
  • Low intake of vegetables.
  • Low intake of fruits.
  • High intake of red meat.
  • High intake of sugar sweetened beverages.

The authors concluded: “More than 80,000 new cancer cases [per year] are estimated to be associated with suboptimal diet among US adults…Our findings underscore the need for reducing cancer burden in the United States by improving the intake of key food groups and nutrients of Americans.”

For more details, read the article above. For example, I discuss which foods we should eliminate, which foods we should eat more of, and which foods we should balance in our diet. To add a more holistic perspective, I also discuss the American Cancer Society’s recommendations for reducing cancer risk.

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