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.

Could Omega-3s Improve Reading Skills?

Can DHA  Help Johnny Read?

Author: Dr. Stephen Chaney

Child-Reading-BookIf you are like most parents, you want to do everything you can to assure that your kids have the skills they need to succeed in school, and reading probably tops the list of necessary skills. If your child is reading below their age level, could something as simple as better nutrition improve their reading ability?

Recent studies have shown that the omega-3 fatty acids, especially DHA, play a very important role in normal brain function – especially memory, focus, concentration, and attention span.

I have shared with you previous studies which have shown that optimal DHA intake in pregnant women plays an important role in the early mental development of their children. On the other end of the age spectrum, studies have shown that optimal omega-3 fatty acid intake in older adults can delay cognitive decline.

I have also shared with you studies showing that omega-3 fatty acid supplementation in children with ADD and ADHD significantly reduce their symptoms. What about children without hyperactivity? Could omega-3 fatty acids affect their ability to learn?

Many Children Are Deficient in Omega-3 Fatty Acids

The Food and Nutrition Board has not yet set US standards for DHA intake, but the international standard is 200 mg for children 7 years old and older. Unfortunately, cod liver oil is a thing of the past, and foods rich in DHA are not particularly popular with children. Consequently, most children in this country are only getting around 20-40 mg of DHA per day.

And that shows up in their blood levels of omega-3 fatty acids. A recent study in England looked at blood levels of omega-3 fatty acids in 493 seven to nine year olds with below average reading performance who were enrolled in Oxfordshire primary schools (P. Montgomery et al, PLoS ONE, doi: 10.1371/journal.pone.0066697).

All of them had low blood levels of omega-3 fatty acids (both DHA and EPA), and the blood levels of omega-3 fatty acids were directly related to their reading ability. In non-scientific language that simply means that those with the poorest reading abilities had the lowest blood levels of omega-3 fatty acids.

This study is particularly significant because another study by the same group showing that DHA supplementation improved reading skills in underperforming children.

Could Omega-3s Improve Reading Skills?

This study (Richardson et al., PLoS ONE 7: e43909.doi:10.1371/journal.pone.0043909) looked at 362 normal 7-9 year old children enrolled in mainstream primary schools in Oxfordshire, England.

These children were all reading at significantly below the average for their grade levels. The study excluded children with specific medical difficulties that might affect their ability to read, children who were already taking medications expected to affect behavior or learning, children for whom English was not their first language, and children who were already eating fish more than twice a week or taking omega-3 supplements.

The children were given either supplements containing 600 mg of DHA per day or a placebo containing corn and soybean oil. At the end of 16 weeks the children were rescored on a standardized reading test.

Reading-ScoresThe results were quite interesting. When the scientists looked at children reading in the lower third of their class, the affect of DHA on their ability to read was non-significant. However, when they looked at the children who were performing in the bottom 20% of their class with respect to reading, DHA supplementation resulted in a 20% improvement in their reading score. And when they looked at children in the bottom 10% of their class with respect to reading, DHA supplementation resulted in a 50% increase in reading scores. These changes were highly significant.

To put this in perspective, the children performing in the bottom 20% of their class improved their reading efficiency by around 0.8 months with respect to their normal reading age, and the children in the bottom 10% of their class improved their reading efficiency by around 1.9 months with respect to their normal reading age.

Strengths and Weaknesses of The Studies

 

On The Minus Side:

  • First and foremost we must remember that nutrition is only one of many factors that can affect reading performance in children. You shouldn’t think of DHA as a magic bullet that will cure your child’s reading problems by itself.
  • This is a single pair of studies that need to be replicated.
  • This study does not establish the optimal dose of DHA needed to improve reading in underperforming children. Until dose response studies have been done we don’t know whether 600 mg is needed or whether simply making sure that the children reach the recommended 200 mg per day of DHA would be sufficient.

On The Plus Side:

  • Both of these were very well controlled studies, and they complemented each other perfectly.  One study showed that students with the poorest reading ability had the lowest blood levels of DHA. The other study showed that children with the poorest reading ability experienced the greatest improvement with DHA supplementation.
  • These studies were not done with third world children. They were studies with normal, healthy children in a prosperous European country.
  • These studies are fully consistent with previous studies looking at the effects of DHA on cognition in children.

The Bottom Line

What does this study mean for parents whose children may be struggling with their reading in school?

  • The lead author concluded: “We have shown that in the mainstream, general population, something as simple as DHA can benefit reading abilities in underperforming children.”
  • It’s perhaps not that ironclad yet. But if your kid or grandkid is reading below their grade level, DHA supplementation is both safe and inexpensive. It’s worth giving it a try.

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

Omega-3 Fatty Acid Deficiency And ADHD: Do The Effects Worsen From Generation to Generation

The Seventh Generation Revisited

Author: Dr. Stephen Chaney

Angry boy portraitDo the effects of omega-3 fatty acid deficiency on ADHD get worse from one generation to the next?

When I was a young man I read an article called “The Seventh Generation” in Organic Gardening magazine. That article was based on the old Indian admonition to consider the effects of everything we do on the seventh generation of our descendents.

The article was written before the environmental movement had co-opted the seventh generation concept. It was also written at a time when the food industry and the public had really started buying into the “better living through chemistry” concept. Processed foods, fast foods and artificial ingredients had just started to replace real foods in the American diet.

The author envisioned a world in which, if we continued to eat nutrient depleted foods, each generation would be sicker than the previous generation until by the seventh generation our descendents would live miserable, sickly, shortened lives – and nobody would know why.

That article made a powerful impression on me. I always like to keep my mind open to new ideas, especially ideas that challenge my preconceived thinking.

So I asked myself “Could it be true? Could eating nutrient depleted foods actually make each generation sicker than the previous generation?”

The author did not have the foresight to predict the obesity epidemic, so he did not envision a world in which we might live sicker, shorter lives in as little as one or two generations.

In addition the author was not a scientist, and his whole premise seemed scientifically implausible at the time. In those days we thought of DNA as the sole determinant of our genetic potential and as something that could not be influenced by our environment. Now we know the DNA and the proteins that coat the DNA can be influenced by the foods we eat and other environmental factors – and that those changes can be passed down from generation to generation. This has lead to a whole new scientific discipline called epigenetics.

Could it be true?

All of that leads me to this week’s article (Bondi et al, Biological Psychiatry, doi:10.1016/j.biosych.2013.06.007). Let me start by pointing out that this is an animal study. It was done with rats. I usually base my health tips on human clinical trials, but it is simply not possible to do multi-generation studies in humans.

The authors hypothesized that omega-3 fatty acid deficiency could be associated with psychiatric disorders such as ADHD, autism, schizophrenia and depression. They based this hypothesis on the known role of omega-3 fatty acids in both brain development and maintenance of normal brain function. They also pointed to numerous clinical studies showing that omega-3 fatty acids could either prevent or reduce the severity of these diseases in humans.

They focused on adolescent rats as well as adult rats because these diseases frequently emerge, and are sometimes more severe, during the adolescent years in humans. Finally, they included second generation rats in the study because the change in our food supply that created an excess of omega-6 fatty acids and a deficiency of omega-3 fatty acids started in the 1960s and 1970s. They reasoned that if the effect of omega-3 deficiency is multigenerational it would be more severe in today’s human adolescents. As I said before, you can’t do multigenerational studies in humans, but you can do them in rats.

They separated litters of rat pups from omega-3 sufficient parents into two groups. One group was fed a diet sufficient in omega-3 fatty acids, and the second group was fed an identical diet except that it was deficient in omega-3 fatty acids. When the omega-3 sufficient group reached adulthood, they were mated and their offspring were continued on the same omega-3 sufficient diet. Similarly, when the omega-3 deficient group reached adulthood, they were mated and their offspring were raised on the same omega-3 deficient diet.

They put each group of rats through a series of behavioral tests when they were adolescents and again when they were adults. It is beyond my expertise to analyze the validity of rat behavioral assays, but the authors claim that the tests they employed were good measures of behavioral traits in human that would be classified as hyperactivity, anxiety, attention deficit disorder and reduced behavioral flexibility. [If you have adolescents in your household, some of those behaviors may sound awfully familiar].

The results were thought provoking. They found little evidence that omega-3 fatty acid deficiency triggered these behaviors in the first generation rats. However, they found strong evidence that omega-3 fatty acid deficiency triggered each of those behaviors in the second generation rats – and the effect was much stronger in the adolescent rats than in the adult rats.

The Bottom Line

At the present time, it isn’t possible to predict the significance of this study for you. This is a single study. And, it is an animal study. It could mean nothing, or it could mean everything.

We do know that the incidence of ADHD in US children has increased by 38% from 2003 to 2012 – and nobody really knows why. We also know that some studies have shown that the American diet is often deficient in omega-3 fatty acids. These same studies have suggested that providing adequate amounts of omega-3 fatty acids in the diet may prevent or reduce the symptoms of ADHD.

I’m a hard-nosed scientist. So I’m not going to be one of those bloggers who writes sensational headlines claiming that omega-3 fatty acid deficiency, or some other nutritional factor, is the cause of our skyrocketing rates of ADHD.

But, it is enough to make you wonder “What if? Could it be true?”

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