American Omega-3 Deficiency

Written by Dr. Steve Chaney on . Posted in Food and Health, Health Current Events, Omega-3 Deficiency, Supplements and Health

Is There an American Omega-3 Deficiency?

Author: Dr. Stephen Chaney

omega 3 deficiencyOmega-3s have been controversial in recent years.  However, virtually everyone agrees that omega-3 intake in North American is low. But, would you believe that the United States and Canada are dead last with respect to omega-3 status – that we are among the countries with the lowest omega-3 status in the world? Is there an American omega-3 deficiency?  That is what a recent study suggests!

Omega-3 Deficiency in Americans

Previous studies have suggested that the American and Canadian diets were deficient in long chain omega-3s like EPA and DHA, but those studies were based on 24-hour diet recalls or food frequency surveys which might underrepresent the true amount of omega-3s in the diet. Therefore, a group of investigators from the United States and Canada decided to look at blood levels of EPA and DHA.

This study (Stark et al, Progress In Lipid Research, 63: 132-152, 2016) was a meta-analysis of 298 studies that recorded blood levels of EPA and DHA. These studies were from 36 counties and distinct regions around the world. They converted all of the measurements to a common unit expressed as percent by weight of EPA + DHA relative to the total weight of fatty acids in the blood.

American omega-3 deficiencyThey combined all studies from a given country or region to give an average value of percent EPA + DHA and then divided the countries and regions into four groupings based on the average weight percentage of EPA + DHA in the blood. If all that seems confusing, the figure on the right (taken from Stark et al, Progress In Lipid Research, 63: 132-152, 2016) should clear things up.

  • Red = very low (< 4%) EPA + DHA levels
  • Orange = low (4-6%) EPA + DHA levels
  • Yellow = moderate (6-8%) EPA + DHA levels
  • Green = adequate (>8%) EPA + DHA levels
  • Grey = no valid measurements in those countries

It is clear from this study that most Americans and most Canadians don’t do a very good job of incorporating omega-3 fatty acids into their diet, as several previous dietary surveys have suggested.  This could contribute to omega-3 deficiency.

Is The United States Dead Last In Omega-3 Status?

The global map of EPA + DHA blood levels certainly suggests that the United States is among a handful of countries with the very lowest omega-3 status. There are a few caveats, however.

  • As the large areas of grey indicate, there are a number of countries with no valid omega-3 blood measurements. The United States might have lots of company in the very low omega-3 status category.
  • There are some very large countries like Russia which have relatively few omega-3 blood measurements, and those measurements are only from a few regions of the country. The average omega-3 status for the entire country might be lower than indicated in this map.

On the other hand, there are lots of omega-3 blood measurements from countries like Japan, so it is clear that there are countries with much better omega-3 status than the United States.

What Does This Study Mean To You?

The important questions are, of course:Does it matter? What do these blood levels of EPA + DHA actually mean? Is < 4% EPA + DHA low enough to matter? What are the health consequences of low omega-3 status?  If you have an omega-3 deficiency, what are the risks?

Let’s start with the first question: How do we translate a blood level of EPA + DHA into how much we should be getting in our diet? While there is no established Dietary Reference Intake for EPA + DHA, several expert panels and international organizations have made recommendations for EPA + DHA intake. Those recommendations generally range from 250 mg/day to 500 mg/day for general health and 500 mg/day to 1,000 mg/day for heart health. Unfortunately, most people in the United States and Canada consume less than 200 mg/day of omega-3 fatty acids, and most of those are short chain omega-3s that are inefficiently converted to the long chain EPA and DHA.

More importantly, a recent study (Patterson et al, Nutrition Research, 35: 1040-1051, 2015) has examined how much additional EPA + DHA must be consumed by someone eating a typical North American diet to significantly improve their omega-3 status. It showed that:

  • 200 mg/day of EPA + DHA is required to improve omega-3 status from very low to low.
  • 500 mg/day of EPA + DHA is required to improve omega-3 status from very low to moderate.
  • 1250 mg/day of EPA + DHA is required to improve omega-3 status from very low to adequate.

omega-3 for heart healthIt is no surprise that these numbers correlate so well. My recommendation would be to consume at least 500 mg/day of EPA + DHA for general health and at least 1,000 mg/day for heart health.

Now let’s look at the last question: What are the health consequences of low omega-3 status? There are multiple health benefits associated with optimal omega-3 status, but the best evidence is for the beneficial effects of omega-3s on fetal and infant neurodevelopment and heart health. For example:

  • In case you have been confused by recent studies suggesting that omega-3s have no effect on heart health you should know that most of those studies were looking at the effect of EPA + DHA in patients who were already taking 3 or 4 heart medications. The studies actually concluded omega-3s provided no additional benefits in people already taking multiple heart medications. That is a totally different question.

Where Should You Get Your Omega-3s?

fish oil supplementsNow that you know how important the long chain omega-3s, EPA and DHA, are for your health, and you know that most of us have a very poor omega-3 status and therefore have an omega-3 deficiency , your next questions are likely to be: “What’s the best way to improve my omega-3 status?” and “Where can I find EPA and DHA in my diet?” The answer is complicated.

  • Cold water, oily fish like salmon are a great source of EPA and DHA. Unfortunately, our oceans are increasingly polluted and some of those pollutants are concentrated even more in farm raised fish. A few years ago a group of experts published a report in which they analyzed PCB levels in both wild caught and farm-raised fish from locations all around the world (Hites et al, Science 303: 226-229, 2004) . Based on PCB levels alone they recommended that some wild caught salmon be consumed no more than once a month and some farm raised salmon be consumed no more than once every other month!

Unfortunately, when you buy salmon in the grocery store or your favorite restaurant, you can ask whether the salmon is wild or farm-raised, but you have no idea where the salmon came from. You have no idea how safe it is to eat. I love salmon and still eat it on occasion, but not nearly as frequently as I used to.

As an aside, the buzzword nowadays is sustainability. I support sustainability. However, the easiest way to assure that fish are sustainable is to raise them in fish farms. When a waiter tells me how sustainable the “catch of the day” is, I ask them how polluted it is. If they can’t answer, I don’t buy it. My health is more important to me than sustainability.

  • Nuts, seeds, and canola oil are good sources of ALA, a short chain omega-3 fatty acid. These food sources are less likely to be contaminated, but the efficiency of conversion of ALA to EPA and DHA is only around 5-10%. In other words, you need to eat a lot of ALA-rich foods to enjoy the health benefits associated with EPA and DHA.
  • That leaves fish oil supplements, but you need to remember that the EPA + DHA supplements you purchase in the health food store come from polluted fish. Unfortunately, many manufacturers have inadequate purification and quality control standards. In other words, neither you nor they know whether their omega-3 products are pure. You need to make sure that the omega-3 supplement you purchase is made by a manufacturer with stringent quality control standards.

 

The Bottom Line

 

  • A recent study has shown that most Americans are deficient in long chain omega-3s like EPA and DHA. In fact, the mainland United States and Canada were tied with half a dozen other countries for the lowest omega-3 status in the world.  Omega-3 deficiency in Americans seems to be the worst.
  • That is unfortunate because recent studies have shown that optimal blood levels of EPA and DHA are associated with a number of health benefits, especially fetal and infant neurodevelopment and heart health.
  • Other studies suggest that most Americans should consume an extra 500 mg/day of EPA + DHA for general health and at least 1,000 mg/day for heart health.
  • Unfortunately, it is not easy get those levels of EPA and DHA from our diet:
  • Oily, cold water fish are a great source of EPA and DHA, but our oceans are increasingly polluted and experts recommend that some fish that are the best sources of EPA and DHA be consumed no more than once a month. The situation is even worse for farm-raised fish.
  • Of course, nowadays the buzzword for fish is sustainability, but sustainability does not guarantee purity. Sustainable fish can be just as polluted as the worst of the farm raised fish.
  • seeds and canola oil are great sources for ALA, a short chain omega-3 fatty acid. This source of omega-3s is less likely to be contaminated, but the efficiency of conversion of ALA to EPA and DHA in our bodies is only around 5-10%.
  • Fish oil supplements can be a convenient source of the EPA and DHA you need, but the fish oil often comes from polluted fish and many manufacturers have inadequate purification methods and quality control standards. If you choose fish oil supplements as your source of omega-3s, be sure to choose a manufacturer with stringent quality control standards. Otherwise, neither you nor the manufacturer will know whether their omega-3 supplement is pure.

 

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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Can Plant-based Diets Be Unhealthy?

Posted September 10, 2019 by Dr. Steve Chaney

Do Plant-Based Diets Reduce Heart Disease Deaths?

Author: Dr. Stephen Chaney

 

plant-based diets vegetablesPlant-based diets have become the “Golden Boys” of the diet world. They are the diets most often recommended by knowledgeable health and nutrition professionals. I’m not talking about all the “Dr. Strangeloves” who pitch weird diets in books and the internet. I am talking legitimate experts who have spent their life studying the impact of nutrition on our health.

Certainly, there is an overwhelming body of evidence supporting the claim that plant-based diets are healthy. Going on a plant-based diet can help you lower blood pressure, inflammation, cholesterol and triglycerides. People who consume a plant-based diet for a lifetime weigh less and have decreased risk of heart disease, diabetes, and cancer.

But, can a plant-based diet be unhealthy? Some people consider a plant-based diet to simply be the absence of meat and other animal foods. Is just replacing animal foods with plant-based foods enough to make a diet healthy?

Maybe not. After all, sugar and white flour are plant-based food ingredients. Fake meats of all kinds abound in our grocery stores. Some are very wholesome, but others are little more than vegetarian junk food. If you replace animal foods with plant-based sweets, desserts, and junk food, is your diet really healthier?

While the answer to that question seems obvious, very few studies have asked that question. Most studies on the benefits of plant-based diets have compared population groups that eat a strictly plant-based diet (Seventh-Day Adventists, vegans, or vegetarians) with the general public. They have not looked at variations in plant food consumption within the general public. Nor have they compared people who consume healthy and unhealthy plant foods.

This study (H Kim et al, Journal of the American Heart Association, 8:e012865, 2019) was designed to fill that void.

 

How Was The Study Done?

plant-based diets studyThis study used data collected from 12,168 middle aged adults in the ARIC (Atherosclerosis Risk in Communities) study between 1987 and 2016.

The participant’s usual intake of foods and beverages was assessed by trained interviewers using a food frequency questionnaire at the time of entry into the study and again 6 years later.

Participants were asked to indicate the frequency with which they consumed 66 foods and beverages of a defined serving size in the previous year. Visual guides were provided to help participants estimate portion sizes.

The participant’s adherence to a plant-based diet was assessed using four different well-established plant-based diet scores. For the sake of simplicity, I will include 3 of them in this review.

  • The PDI (Plant-Based Diet Index) categorizes foods as either plant foods or animal foods. A high PDI score means that the participant’s diet contains more plant foods than animal foods. A low PDI score means the participant’s diet contains more animal foods than plant foods.
  • The hPDI (healthy plant-based diet index) is based on the PDI but emphasizes “healthy” plant foods. A high hPDI score means that the participant’s diet is high in healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, coffee and tea) and low in animal foods.
  • The uPDI (unhealthy plant-based diet index) is based on the PDI but emphasizes “unhealthy” plant foods. A high uPDI score means that the participant’s diet is high in unhealthy plant foods (refined grains, fruit juices, French fries and chips, sugar sweetened and artificially sweetened beverages, sweets and desserts) and low in animal foods.

For statistical analysis the scores from the various plant-based diet indices were divided into 5 equal groups. In each case, the group with the highest score consumed the most plant foods and least animal foods. The group with the lowest score consumed the least plant foods and the most animal foods.

The health outcomes measured in this study were heart disease events, heart disease deaths, and all-cause deaths. Again, for the sake of simplicity, I will only include 2 of these outcomes (heart disease deaths and all-cause deaths) in this review. The data on deaths were obtained from state death records and the National Death Index. (Yes, your personal information is available on the web even after you die.)

 

Do Plant-Based Diets Reduce Heart Disease Deaths?

plant-based diets reduce heart deathsThe participants in this study were followed for an average of 25 years.

The investigators looked at heart disease deaths over the 25 years and compared people with the highest intake of plant foods to people with the highest intake of red meat and other animal foods. The results were:

  • People with the highest intake of plant foods and the highest intake of healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, coffee and tea) had a 19-32% lower risk of dying from heart disease than people with the highest intake of red meat and other animal foods.
  • People with the highest intake of unhealthy plant foods (refined grains, fruit juices, French fries and chips, sugar sweetened and artificially sweetened beverages, sweets and desserts) had the same risk of dying from heart disease as people with the highest intake of red meat and other animal foods.

When the investigators looked at all-cause deaths over the 25 years:

  • People with the highest intake of plant foods and the highest intake of healthy plant foods had an 11-25% lower risk of dying from any cause than people with the highest intake of red meat and other animal foods.
  • People with the highest intake of unhealthy plant foods had the same risk of dying from heart disease as people with the highest intake of red meat and other animal foods.

What Else Did The Study Show?

The investigators made a couple of other interesting observations:

  • The association of the overall diet with heart disease and all-cause deaths was stronger than the association of individual food components. This underscores the importance of looking at the effect of the whole diet on health outcomes rather than the “magic” foods you hear about on Dr. Strangelove’s Health Blog.
  • Diets with the highest amount of healthy plant foods were associated with higher intake of carbohydrates, plant protein, fiber, and micronutrients, including potassium, magnesium, iron, vitamin A, vitamin C, folate, and lower intake of saturated fat and cholesterol.
  • Diets with the highest amount of unhealthy plant foods were associated with higher intake of calories and carbohydrates and lower intake of fiber and micronutrients.

The last two observations may help explain some of the health benefits of plant-based diets.

 

Can Plant-Based Diets Be Unhealthy?

plant-based diets unhealthy cookiesNow, let’s return to the question I asked at the beginning of this article: “Can plant-based diets be unhealthy?” Although some previous studies have suggested that unhealthy plant-based diets might increase the risk of heart disease, this study did not show that.

What this study did show was that an unhealthy plant-based diet was no better for you than a diet containing lots of red meat and other animal foods.

If this were the only conclusion from this study, it might be considered a neutral result. However, this result clearly contrasts with the data from this study and many others showing that both plant-based diets in general and healthy plant-based diets reduce the risk of heart disease deaths and all-cause deaths compared to animal-based diets.

The main message from this study is clear.

  • Replacing red meat and other animal foods with plant foods can be a healthier choice, but only if they are whole, minimally processed plant foods like whole grains, fruits, vegetables, nuts, legumes, coffee and tea.
  • If the plant foods are refined grains, fruit juices, French fries and chips, sugar sweetened and artificially sweetened beverages, sweets and desserts, all bets are off. You may be just as unhealthy as if you kept eating a diet high in red meat and other animal foods.

There is one other subtle message from this study. This study did not compare vegans with the general public. Everyone in the study was the general public. Nobody in the study was consuming a 100% plant-based diet.

For example:

  • The group with the highest intake of plant foods consumed 9 servings per day of plant foods and 3.6 servings per day of animal foods.
  • The group with the lowest intake of plant foods consumed 5.4 servings per day of plant foods and 5.6 servings per day of animal foods.

In other words, you don’t need to be a vegan purist to experience health benefits from adding more whole, minimally processed plant foods to your diet.

 

The Bottom Line

A recent study analyzed the effect of consuming plant foods on heart disease deaths and all-cause deaths over a 25-year period.

When the investigators looked at heart disease deaths over the 25 years:

  • People with the highest intake of plant foods and the highest intake of healthy plant foods had a 19-32% lower risk of dying from heart disease than people with the highest intake of red meat and other animal foods.
  • People with the highest intake of unhealthy plant foods had the same risk of dying from heart disease as people with the highest intake of red meat and other animal foods.

When the investigators looked at all-cause deaths over the 25 years:

  • People with the highest intake of plant foods and the highest intake of healthy plant foods had an 11-25% lower risk of dying from any cause than people with the highest intake of red meat and other animal foods.
  • People with the highest intake of unhealthy plant foods had the same risk of dying from heart disease as people with the highest intake of red meat and other animal foods.

The main message from this study is clear.

  • Replacing red meat and other animal foods with plant foods can be a healthier choice, but only if they are whole, minimally processed plant foods like whole grains, fruits, vegetables, nuts, legumes, coffee and tea.
  • If the plant foods are refined grains, fruit juices, French fries and chips, sugar sweetened and artificially sweetened beverages, sweets and desserts, all bets are off. You may be just as unhealthy as if you kept eating a diet high in red meat and other animal foods.

A more subtle message from the study is that you don’t need to be a vegan purist to experience health benefits from adding more whole, minimally processed plant foods to your diet. The people in this study were not following some special diet. The only difference was that some of the people in this study ate more plant foods and others more animal foods.

For more details on the 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.

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