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.

Will Plant Proteins Help You Live Longer?

Is A Vegan Diet Healthiest?

Author: Dr. Stephen Chaney

Fountain Of YouthUnless you are Rip Van Winkle and have been asleep for the past 40 years, you have probably heard that whole food, primarily plant-based diets are good for you.

  • They help you control your weight.
  • They reduce inflammation.
  • They reduce your risk of diabetes and heart disease.
  • They even reduce your risk of some cancers.

But do they help you live longer? If we take that question literally, the answer appears to be no. There is no “Fountain Of Youth”. There are no diets that extend our lives significantly.

However, what if you could reduce your risk of premature death? It would be tragic to have your life cut short by a heart attack or some other major disease. What if you could prevent that?

And what if you could live healthier longer? It would be equally tragic to spend your golden years debilitated by chronic diseases like heart disease, diabetes, or dementia. What if you could delay these diseases and live healthier longer?

The study I discuss this week (Y Sun, Journal of the American Heart Association, 10:e015553, 2021) looks at the effect of different dietary protein sources on premature death.

This study, like many others, suggests that primarily plant-based diets are healthier than meat-based diets. But what does this mean for you? Should you go completely meatless? Is a vegan diet healthier than other plant-based diets? I discuss what we know and what we do not know about the vegan diet compared to other plant-based diets.

How Was This Study Done?

Clinical StudyThe data for this study were drawn from the Women’s Health Initiative (WHI). The Women’s Health Initiative was designed to help identify strategies for preventing heart disease and other diseases in postmenopausal women. It enrolled 161,000 postmenopausal women from 40 sites across the US between 1993 and 1998 and followed them through 2017.

This study excluded women who had heart disease or cancer when they entered the WHI study and women who had incomplete data on either their diet or their use of postmenopausal hormone therapy. They were left with 102,521 women, age 50-79 at time of entry, who were followed for 18 years.

Each woman filed out an extensive dietary survey at the beginning of the study. There were 25,976 deaths during the study. The cause of death was determined by reviewing death certificates, medical records, autopsy reports or by linkage to the National Death Index.

The investigators asked whether women who ate more plant proteins were healthier than those who ate primarily meat protein. To answer this question, they correlated protein sources in the diet with all-cause mortality and deaths from various diseases.

The greatest difficulty with this type of study is that people who eat more plant protein tend to have a healthier diet and a healthier lifestyle. That makes it hard to separate out the benefits of eating plant proteins from benefits associated with other aspects of their diet and lifestyle. So, the authors corrected their data for every factor known to influence the risk of heart disease, diabetes, dementia, and premature death.

Specifically, the data were statistically corrected for age, race/ethnicity, socioeconomic status, hormone use, lifestyle (smoking status, physical activity, and alcohol intake), baseline health status (diabetes and/or high blood cholesterol), family history of heart attack/stroke, dietary factors (calorie intake, dietary fiber intake, whole grain consumption, fruit and vegetable consumption, sugar-sweetened beverage consumption, glycemic load (effect of foods in the diet on blood sugar), and percentage of saturated fats, polyunsaturated fats, monounsaturated fats, and trans fats), and weight (BMI).

In short, the authors corrected for every other factor that could influence disease risk and/or premature death. By doing so, they were able to focus on the effect of protein sources on disease risk and/or premature death.

Will Plant Proteins Help You Live Longer?

Plant ProteinsThe investigators divided the study participants into quintiles with respect the kind and amount of protein they consumed.

  • For animal protein, the intake ranged from 4 ounces/day in the lowest quintile to 9 ounces a day in the highest quintile (For comparison, 3 ounces is roughly equivalent to the size of a deck of cards).
  • For plant protein, the intake ranged from 2 ounces/day in the lowest quintile to 3.5 ounces/day in the highest quintile.
  • When you combine plant and animal protein in these women’s diet, plant protein ranged from 18% of total protein intake in the lowest quintile to 48% of total protein intake in the highest quintile.

When women who had the highest intake for plant protein were compared with women who had the lowest intake of plant protein, the women with the highest plant protein intake had:

  • 12% lower risk of premature death from heart disease.
  • 21% lower risk of premature death from dementia.
  • 9% lower risk of premature death from all causes.

There was an inverse relationship between the amount of plant protein in the diet and premature death. Specifically, every 3 ounces of animal protein that was replaced with 3 ounces of plant protein resulted in:

  • 22% lower risk of premature death from heart disease.
  • 19% lower risk of premature death from dementia.
  • 14% lower risk of premature death from all causes.

The Effect Of Individual Animal Proteins On Mortality

Fatty SteakThe authors also looked at the effect of various animal proteins on premature death. For example:

Red Meat: Women with the highest consumption of red meat had:

  • 14% higher risk of premature death from heart disease.
  • 20% higher risk of premature death from dementia.
  • 10% higher risk of premature death from all causes.

Eggs: Women with the highest consumption of eggs had:

  • 24% higher risk of premature death from heart disease.
  • 14% lower risk of premature death from dementia.
  • 14% higher risk of premature death from all causes.

Dairy: Women with the highest consumption of dairy had:

  • 11% higher risk of premature death from heart disease.

The authors concluded, “In this large prospective cohort study, we found that higher plant protein intake and substitution of animal protein with plant protein were associated with lower risk of all-cause mortality, cardiovascular mortality, and dementia mortality…Our findings support the need for consideration of protein sources, in addition to the amount of protein intake, in future dietary guidelines.”

Is A Vegan Diet Healthiest?

Vegetarian DietYears ago, as my brother-in-law was coming out of anesthesia at the end of quadruple bypass surgery, the first question he asked was, “Does this mean I need to eat tofu?” Obviously, nothing terrified him more than the thought of eating tofu the rest of his life. In the same vein, some of you are probably asking, “Does this mean I need to go vegan?”

The good news is that none of the women in this study were consuming a vegan diet. They were consuming a typical American diet with varying amounts of plant and animal protein. The group with the highest plant protein consumption were still getting 52% of their protein from animal sources.

This study shows that even people consuming a typical American diet can become healthier by simply swapping out some of the animal protein in their diet with plant protein.

However, you are probably thinking, “Plant protein is good for us, and a vegan diet is 100% plant protein. Does that mean a vegan diet is healthier than other plant-based diets?

The answer is………”Maybe”

If the linear relationship between plant protein consumption and risk of premature death could be extrapolated all the way to 100% plant protein, the answer would be obvious. Vegan diets would be healthier than other plant-based diets. But that extrapolation is an assumption. It might not be true.

For example, some recent studies suggest that completely eliminating meat, eggs, and dairy from your diet may slightly increase your risk of heart disease and stroke:

  • One recent study found that adding 1.4 ounces of fish/day to a primarily vegetarian diet decreases the risk of stroke by 20%.
  • Another study reported that adding one egg/day to a primarily vegetarian diet decreases the risk of heart disease by 12% and stroke by 10-26%.

These studies need to be confirmed, but they do suggest we need to be cautious about assuming that vegan diets are healthier than other primarily plant-based diets. This is why, when I recommend primarily plant-based diets, I include everything from vegan through semi-vegetarian, Mediterranean, and DASH.

They are all healthy diets. My advice is to choose the one that best fits your lifestyle and food preferences. And focus on whole foods, not processed foods.

The Bottom Line 

A recent study asked whether women who ate more plant proteins were healthier than those who ate primarily meat protein. To answer this question, the investigators correlated protein sources in the diet with all-cause mortality and deaths from various diseases.

When women who had the highest intake for plant protein were compared with women who had the lowest intake of plant protein, the women with the highest plant protein intake had:

  • 12% lower risk of premature death from heart disease.
  • 21% lower risk of premature death from dementia.
  • 9% lower risk of premature death from all causes.

There was an inverse relationship between the amount of plant protein in the diet and premature death. Specifically, every 3 ounces of animal protein that was replaced with 3 ounces of plant protein resulted in:

  • 22% lower risk of premature death from heart disease.
  • 19% lower risk of premature death from dementia.
  • 14% lower risk of premature death from all causes.

[Note: A 3-ounce serving is roughly equivalent to a deck of cards.]

The authors concluded, “In this large prospective cohort study, we found that higher plant protein intake and substitution of animal protein with plant protein were associated with lower risk of all-cause mortality, cardiovascular mortality, and dementia mortality…Our findings support the need for consideration of protein sources, in addition to the amount of protein intake, in future dietary guidelines.”

Years ago, as my brother-in-law was coming out of anesthesia at the end of quadruple bypass surgery, the first question he asked was, “Does this mean I need to eat tofu?” Obviously, nothing terrified him more than the thought of eating tofu the rest of his life. In the same vein, some of you are probably asking, “Does this mean I need to go vegan?”

I discuss the answer to that question in the article above.

For more details and a discussion about the vegan diet versus other primarily plant-based diets 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.

Health Tips From The Professor