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

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

Author: Dr. Stephen Chaney

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

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

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

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

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

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

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

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

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

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

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

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

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

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

How Was This Study Done?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The Bottom Line

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

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

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

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

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

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

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

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

For more details about this study, read the article above.

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

Do Omega-3s Add Years To Your Life?

Why Are Omega-3s So Controversial? 

Author: Dr. Stephen Chaney

ArgumentI don’t need to tell you that omega-3s are controversial. Some experts confidently tell you that omega-3s significantly reduce your risk of heart disease and may reduce your risk of cancer and other diseases. Other experts confidently tell you that omega-3s have no effect on heart disease or any other disease. They claim that omega-3 supplements are no better than “snake oil”.

The problem is that each camp of experts can cite published clinical studies to support their claims. How can that be? How can clinical studies come to opposite conclusions on such an important topic? The problem is that it is really difficult to do high quality clinical studies on omega-3s. I will discuss that in the next section.

The question of whether omega-3s affect life span has also been controversial. Heart disease and cancer are the top two causes of death in this country. So, if omega-3s actually reduced the risk of heart disease and cancer, you might expect that they would also help us live longer. Once again, there are studies on both sides of this issue, but they are poor quality studies.

We need more high-quality studies to clear up the controversies surrounding the health benefits of omega-3s. I will report on one such study in this issue of “Health Tips From The Professor”. But first let me go into more depth about why it is so difficult to do high-quality studies with omega-3 fatty acids.

Clinical Studies 101: Why Are Omega-3s So Controversial?

professor owlI have covered this topic in previous issues of “Health Tips From the Professor”, but here is a quick summary.

  1. Randomized, placebo controlled clinical trials (RCTs) are considered the gold standard for evidence-based medicine, but they ill-suited to measure the effect of omega-3s on health outcomes.
    • Heart disease and cancer take decades to develop. Most RCTs are too small and too short to show a meaningful effect of omega-3s on these diseases.
    • To make up for this shortcoming, some recent RCTs have started with older, sicker patients. This way enough patients die during the study that it can measure statistically significant outcomes. However, these patients are already on multiple medications that mimic many of the beneficial effects of omega-3s on heart disease.

These studies are no longer asking whether omega-3s reduce the risk of heart disease. They are really asking if omega-3s have any additional benefits for patients who are already taking multiple medications – with all their side effects. I don’t know about you, but that is not the question I am interested in.

    • Until recently, most RCTs did not measure circulating omega-3 levels before and after supplementation, so the investigators had no idea whether omega-3 supplementation increased circulating omega-3 levels by a significant amount.

And for the few studies where omega-3 levels were measured before and after supplementation, it turns out that for many of the participants, their baseline omega-3 levels were too high for omega-3 supplementation to have a meaningful effect. Only participants with low omega-3 levels at the beginning of the study benefited from omega-3 supplementation.Supplementation Perspective

These studies are often quoted as showing omega-3 supplementation doesn’t work. However, they are actually showing the true value of supplementation. Omega-3 supplementation isn’t for everyone. It is for people with poor diet, increased need, genetic predisposition, and/or pre-existing disease not already treated with multiple medications.

2) Prospective cohort studies eliminate many of the shortcomings of RCTs. They can start with a large group of individuals (a cohort) and follow them for many years to see how many of them die or develop a disease during that time (this is the prospective part of a prospective cohort trial). This means they can start with a healthy population that is not on medications.

This also means that these studies can answer the question on most people’s minds, “Are omega-3s associated with reduced risk of dying or developing heart disease?” However, these studies have two limitations.

    • They are association studies. They cannot measure cause and effect.
    • Ideally, omega-3 levels would be measured at the beginning of the study and at several intervals during the study to see if the participant’s diet had changed during the study. Unfortunately, most prospective cohort studies only measure omega-3 levels at the beginning of the study.

3) Finally, a meta-analysis combines data from multiple clinical studies.

    • The strength of a meta-analysis is that the number of participants is quite large. This increases the statistical power and allows it to accurately assess small effects.
    • The greatest weakness of meta-analyses is that the design of the individual studies included in the meta-analysis is often quite different. This introduces variations that decrease the reliability of the meta-analysis. It becomes a situation of “Garbage in. Garbage out”

The study (WS Harris et al, Nature Communications, Volume 12, Article number: 2329, 2021) I am discussing today is a meta-analysis of prospective cohort studies. It was designed to determine the association between blood omega-3 fatty acids and the risk of:

  • Death from all causes.
  • Death from heart disease.
  • Death from cancer.
  • Death from causes other than heart disease or cancer.

More importantly, it eliminated the major weakness of previous meta-analyses by only including studies with a similar design.

How Was This Study Done?

Clinical StudyThis study was a meta-analysis of 17 prospective cohort studies with a total of 42,466 individuals looking at the association between omega-3 fatty acid levels in the blood and premature death due to all causes, heart disease, cancer, and causes other than heart disease and cancer.

Participants in the 17 studies were followed for an average of 16 years, during which time 15,720 deaths occurred. This was a large enough number of deaths so that a very precise statistical analysis of the data could be performed.

The average age of participants at entry into the studies was 65, and 55% of the participants were women. Whites constituted 87% of the participants, so the results may not be applicable to other ethnic groups. None of the participants had heart disease or cancer when they entered the study.

Finally, the associations were corrected for a long list of variables that could have influenced the outcome (Read the publication for more details).

A strength of this meta-analysis is that all 17 studies were conducted as part of the FORCE (Fatty Acids & Outcomes Research Consortium) collaboration. The FORCE collaboration was established with the goal of understanding the relationships between fatty acids (as measured by blood levels of the omega-3 fatty acids) on premature death and chronic disease outcomes (cardiovascular disease, cancer, and other conditions).

Each study was designed using a standardized protocol, so that the data could be easily pooled for a meta-analysis. In the words of the FORCE collaboration founders:

  1. The larger sample sizes of [meta-analyses] will substantially increase statistical power to investigate associations…enabling the [meta-analyses] to discover important relationships not discernible in any individual study.

2) Standardization of variable definitions and modeling of associations will reduce variation and potential bias in estimates across cohorts.

3) Results will be far less susceptible to publication bias.

Do Omega-3s Add Years To Your Life?

Omega-3sThe meta-analysis divided participants into quintiles based on blood omega-3 levels. When comparing participants with the highest omega-3 levels with participants with the lowest omega-3 levels:

  • Premature death from all causes was decreased by 16%.
    • When looking at the effect of individual omega-3s, EPA > EPA+DHA > DHA.
  • Premature death from heart disease was decreased by 19%.
    • When looking at the effect of individual omega-3s, DHA > EPA+DHA > EPA.
  • Premature death from cancer was decreased by 15%.
    • When looking at the effect of individual omega-3s, EPA > DHA > EPA+DHA.
  • Premature death from causes other than heart disease and cancer was decreased by 18%.
    • When looking at the effect of individual omega-3s, EPA > EPA+DHA > DHA.
  • The differences between the effects of EPA, DHA, and EPA+DHA were small.
  • ALA, a short chain omega-3 found in plant foods, had no effect on any of these parameters.

In the words of the authors: “These findings suggest that higher circulating levels of long chain omega-3 fatty acids are associated with a lower risk of premature death. Similar relationships were seen for death from heart disease, cancer, and causes other than heart disease and cancer. No associations were seen with the short chain omega-3, ALA [which is found in plant foods]”.

What Does This Study Mean For You?

confusionIf you are thinking that 15-19% decreases in premature death from various causes don’t sound like much, let me do some simple calculations for you. The average lifespan in this country is 78 years.

  • A 16% decrease in death from all causes amounts to an extra 12.5 years. What would you do with an extra 12.5 years?
  • A 19% decrease in death from heart disease might not only allow you to live longer, but it has the potential to improve your quality of life by living an extra 15 years free of heart disease.
  • Similarly, a 15% decrease in death from cancer might help you live an extra 12 years cancer-free.
  • In other words, you may live longer, and you may also live healthier longer, sometimes referred to as “healthspan”.

Don’t misunderstand me. Omega-3s are not a magic wand. They aren’t the fictional “Fountain of Youth”.

  • There are many other factors that go into a healthy lifestyle. If you sit on your couch all day eating Big Macs and drinking beer, you may be adding the +12.5 years to a baseline of -30 years.
  • Clinical studies report average values and none of us are average. Omega-3s will help some people more than others.

I will understand if you are skeptical. It seems like every time one study comes along and tells you that omega-3s are beneficial, another study comes along and tells you they are worthless.

This was an extraordinarily well-designed study, but it is unlikely to be the final word in the omega-3 controversy. There are too many poor-quality studies published each year. Until everyone in the field agrees to some common standards like those in the FORCE collaboration, the omega-3 controversy will continue.

The Bottom Line 

A recent meta-analysis looked at the association between omega-3 fatty acid levels in the blood and premature death due to all causes, heart disease, cancer, and causes other than heart disease and cancer.

The meta-analysis divided participants into quintiles based on blood omega-3 levels. When comparing participants with the highest omega-3 levels with participants with the lowest omega-3 levels:

  • Premature death from all causes was decreased by 16%.
  • Premature death from heart disease was decreased by 19%.
  • Premature death from cancer was decreased by 15%.
  • Premature death from causes other than heart disease and cancer was decreased by 18%.

In the words of the authors: “These findings suggest that higher circulating levels of long chain omega-3 fatty acids are associated with a lower risk of premature death. Similar relationships were seen for death from heart disease, cancer, and causes other than heart disease and cancer.”

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

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

 

 

Can Vitamin C Prevent Heart Disease?

Where Should I Get My Vitamin C?

vitamin CThe vitamin C controversy continues. Some people call vitamin C a “miracle” nutrient. Others consider it little more than “fairy dust”. What is the truth?

Let’s look at the effect of vitamin C on heart disease risk as an example of why it is so difficult to resolve questions like this.

Association studies are ideal for measuring long-term effects of nutrient consumption on health outcomes. These studies have consistently found an inverse association between dietary vitamin C and plasma vitamin C levels with the risk of heart disease. Simply put, the more vitamin C from dietary sources, the lower the risk of heart disease.

However, association studies do not prove cause and effect. The primary reason for this is that association studies are complicated by “confounding variables”. For example, most vitamin C in the diet comes from fruits and vegetables. So, the question arises, “Is it the vitamin C in fruits and vegetables that is responsible for the decreased heart disease risk, or is it the fiber that is also present in fruits and vegetables?” Previous studies have not been designed to answer this question.

Placebo-controlled clinical trials solve the confounding variable issue because they involve supplementation with pure vitamin C or a placebo. There is only a single variable. However, placebo-controlled clinical trials only last for a short time. That means they can measure biological markers that may affect heart disease risk but seldom last long enough to directly measure the effect of vitamin C on heart disease risk.

For example, previous studies have shown that high-dose (500 to 4,000 mg/day) supplementation with vitamin C improves the function of the endothelial lining of our blood cells and reduces blood pressure. These are biological markers that might be expected to reduce heart disease risk.

However, heart disease takes decades to develop. No studies of vitamin C supplementation have lasted long enough to show an actual decrease in heart disease outcomes.

In today’s issue of “Health Tips From The Professor” I would like to address three questions:

1) Does dietary vitamin C reduce heart disease risk?

2) How much of the risk reduction is due to the fiber content of fruits and vegetables rather than their vitamin C content?

3) Does supplementation with vitamin C reduce heart disease risk?

I will focus on a recent study (N Martin-Calvo and MA Martinez-Gonzalez, Nutrients, 9: 954, 2017, doi.org/10.3390/nu909054) that was designed to answer these questions.

How Was The Study Done?

Heart Health StudyThis study was an offshoot of an ongoing Spanish research program called Seguimiento Universidad de Navarra (SUN) follow-up study. This program is following graduates of the University of Navarra to gauge the effect of diet and lifestyle on health outcomes.

Health, lifestyle, and diet information is collected when graduates enroll in the program and by mailed questionnaires every two years thereafter.

Graduates who were enrolled in the SUN program in 2014 or earlier were invited to participate in this vitamin C and heart disease study.

  • Vitamin C intake from diet and from supplements was assessed from the dietary analysis.
  • A diagnosis of heart disease was obtained from the Health questionnaire and confirmed by physician follow-up.
  • Deaths due to heart disease were obtained from the Spanish National Death Index cross-referenced to participants in the study and were confirmed by participants next of kin, work associates, or postal authorities.

The study excluded:

  • Participants with pre-existing heart disease at the beginning of the study.
  • Participants who were younger than 40 at the beginning of the study.
  • Participants with either very high or very low vitamin C intake.

That left 13,421 participants who were young (average age = 42), at a healthy weight (average BMI = 24), healthy, and taking few medications.

Can Vitamin C Prevent Heart Disease?

Healthy HeartThe 13,421 participants in this study were followed for an average of 11 years.

They were divided into three groups based on their vitamin C intake.

  • Group 1 averaged 148 mg/day.
  • Group 2 averaged 257 mg/day.
  • Group 3 averaged 445 mg/day.

There are two noteworthy observations about their vitamin C intake:

  • None of the groups were vitamin C deficient. All three groups were getting well above the RDA for vitamin C (75 mg/day for women and 90 mg/day for men).
  • Most of the vitamin C came from fruits and vegetables in the diet. The group with the highest vitamin C intake (445 mg/day) only averaged about 10 mg/day from supplements.

The results of the study were intriguing. When the investigators compared the group with the highest vitamin C intake to the group with the lowest vitamin C intake:

  • Vitamin C significantly decreased both the risk of developing heart disease and the risk of dying from heart disease.
    • Statistically adjusting the data for age, gender, weight, lifestyle, and medicine use did not affect the outcome.
    • Statistically adjusting the data for fiber from sources other than fruits and vegetables did not affect the outcome.
    • Statistically adjusting the data for adherence to a healthy diet (the Mediterranean diet) did not affect the outcome.

However, when the data were statistically adjusted for total fiber (including fiber from fruits and vegetables) the high fiberresults painted a slightly different picture. With this adjustment:

  • Vitamin C decreased the risk of developing heart disease by 26%, but this decrease was not statistically significant.
  • Vitamin C decreased the risk of dying from heart disease by 70%, and this decrease was highly significant.

This was the first study to consider the relative importance of vitamin C from fruits and vegetables and fiber from fruits and vegetables on heart disease outcomes and the results were interesting. Here are the important conclusions.

1) Both the fiber and the vitamin C from fruits and vegetables contributed to a decreased risk of developing heart disease. This study was unable to separate their contributions.

Of course, it is important to note that this was a young, healthy population, none of whom were deficient in vitamin C. It would be interesting to repeat this study with an older, sicker population with a more restrictive diet.

2) Vitamin C from fruits and vegetables reduced the risk of dying from heart disease independent of the beneficial effects of fruit and vegetable fiber.

3) This study was not able to address the effect of vitamin C supplementation on heart disease risk. That is because the Spaniards supplement much less frequently than Americans and this study excluded anyone with unusually high vitamin C intake. The average supplemental vitamin C in the 3 groups ranged from 0.56 mg/day to 9.6 mg/day.

4) This study also emphasizes the importance of getting fiber from a variety of food sources. It showed that fiber from fruits and vegetables was more beneficial at reducing heart disease risk than fiber from other food sources. That means restrictive diets that eliminate fruits and/or vegetables may be bad for your heart.

Where Should I Get My Vitamin C?

Vegan FoodsThis study reinforces the importance of getting lots of fresh fruits and vegetables in your diet.

  • You could make a list of all the vitamin C-rich fruits and vegetables like citrus fruits, red & green peppers, broccoli, etc. and make sure you are including them in your diet.
  • You could total up the vitamin C in each food you eat and try to reach the 445 mg/day in the group with the highest vitamin C in this study.

However, it doesn’t have to be that complicated. If you eat a primarily plant-based diet, aim for 5-9 servings of fruits and vegetables a day, and “eat the rainbow” you will get plenty of vitamin C from your diet.

Also, don’t worry about whether the benefits of fruit and vegetable consumption come from their vitamin C or from their fiber. That’s the beauty of eating whole foods. You get both in the same package.

Of course, you are probably also wondering whether vitamin C supplementation will reduce your risk of heart disease. As I described earlier, there are lots of reasons for thinking that vitamin C supplementation might decrease heart disease risk.

  • Several studies show that higher vitamin C intake and higher vitamin C levels in the blood are associated with lower heart disease risk.
  • This study showed that vitamin C reduces the risk of dying from heart disease independent of fiber from fruits and vegetables and independent of an overall healthy diet. This suggests that vitamin C plays an independent role in reducing heart disease risk.
  • Placebo controlled clinical trials show that vitamin C supplementation reduces risk factors that contribute to heart disease.

However, none of these studies prove that vitamin C supplementation reduces heart disease risk. That requires placebo-controlled clinical trials measuring the effect of vitamin C supplementation on heart disease outcomes. Unfortunately, these studies are usually doomed to failure.

Chronic diseases like heart disease takes decades to develop. Placebo-controlled, randomized studies are almost never large enough or last long enough to show an effect of supplementation on chronic diseases.

The best we can say at present is that vitamin C supplementation along with a primarily plant-based diet with lots of colorful fruits and vegetables may reduce your risk of heart disease.

The Bottom Line

A recent study in Spain followed 13,421 healthy college graduates with an average age of 42 for 11 years and looked at the effect of vitamin C intake on the risk of developing heart disease and the risk of dying from heart disease.

This was the first study to consider the relative importance of vitamin C from fruits and vegetables and fiber from fruits and vegetables on heart disease outcomes and the results are intriguing. Here are the important conclusions.

1) Both the fiber and the vitamin C from fruits and vegetables contributed to a decreased risk of developing heart disease. This study was unable to separate their contributions.

Of course, it is important to note that this was a young, healthy population, none of whom were deficient in vitamin C. It would be interesting to repeat this study with an older, sicker population with a more restrictive die

2) Vitamin C from fruits and vegetables reduced the risk of dying from heart disease by 70%, and this effect was independent of the beneficial effects of fruit and vegetable fiber.

3) This study was not able to address the effect of vitamin C supplementation on heart disease risk. That is because the Spaniards supplement much less frequently than Americans and this study excluded anyone with unusually high vitamin C intake. The average supplemental vitamin C in the 3 groups ranged from 0.56 mg/day to 9.6 mg/day.

4) This study also emphasizes the importance of getting fiber from a variety of food sources. It showed that fiber from fruits and vegetables was more beneficial at reducing heart disease risk than fiber from other food sources. That means restrictive diets that eliminate fruits and/or vegetables may be bad for your heart.

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.

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.

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