Omega-3 Fatty Acids And Brain Health

Written by Dr. Steve Chaney on . Posted in Food and Health, Issues

Is it How Much You Eat, or How Much You Keep?

Author: Dr. Stephen Chaney

 

Brain HealthWhy do some studies conclude that omega-3 fatty acids are essential for a strong mind, a strong heart and will wipe out inflammation – while other studies suggest that they are ineffective? The simple answer is that nobody really knows.

However, in the process of reviewing two recent studies on omega-3 fatty acids and brain health I made an interesting observation that offers a possible explanation for the discrepancies between studies. And if my hypothesis is correct, it suggests that the design of many of the previous studies with omega-3 fatty acids is faulty.

Omega-3 Fatty Acids And Brain Health

The first study (J.K. Virtanen et al, J Am Heart Assoc, 2013, 2:e000305 doi: 10.1161/JAHA.113.000305) looked at the effect of omega-3 fatty acids on brain function in older adults (>65 years old). It concluded that high omega-3 levels were associated with better white matter grade and a 40% reduction in subclinical infarcts (Sorry for the technical jargon – but both of those are good things in terms of brain function for those of us who are getting a bit older).

The second study (C. M. Milte et al, J of Attention Disorders, 2013, doi: 10.1177/1087054713510562) looked at the effect of omega-3 fatty acids on children (ages 6-13) with ADHD. It concluded that high omega-3 levels were associated with improved spelling and attention and reduced oppositional behavior, hyperactivity, cognitive problems and inattention.

What Is The Common Thread In These Studies?

Why, you might ask, am I comparing a study in the elderly, where the concern is retention of cognitive skills, with a study on ADHD in children?

That’s because there is a very important common thread in those two studies. It wasn’t the amount of omega-3 fatty acids in their diet that counted. It was the levels of omega-3 fatty acids in their blood that made the difference.

The first study included a detailed dietary history to estimate the habitual intake of omega-3 fatty acids in the participants.

  • There was no correlation between estimated dietary intake of omega-3 fatty acids and any measure of brain function in those older adults.
  • However, there was a strong correlation between blood levels of omega-3s and brain health in that population group.

The second study was actually a placebo controlled intervention study in which the children were given 1 gm/day of either omega-3 fatty acids or omega-6 fatty acids.

  • Once again, there was no correlation between dietary intake of omega-3 or omega-6 fatty acids and any outcome related to ADHD.
  • However, there was a strong correlation between blood levels of omega-3 fatty acids or omega-3/omega-6 ratio and improvement in multiple measures of ADHD.

How Could The Effect of Dietary Intake And Blood Levels Of Omega-3s Be So Different?

Fish OilBoth studies were relatively small and suffered from some technical limitations, but the most likely explanations are:

  • Inaccurate recall of the participants as to what they eat on a habitual basis. (study 1)
  • Individual differences in the ability of participants to convert short chain omega-3 fatty acids (found in foods such as canola oil, flaxseed oil and walnuts) to the beneficial long chain fatty acids (found in cold water fish). (study 1)
  • Poor compliance in taking the supplements. (study 2)

Why Are These Studies Important?

The most important insight to come out of both of these studies is that it is essential to actually measure blood levels of omega-3 fatty acids and not just rely on dietary intake or supplementation for a valid clinical trial.

That’s a concern because blood measurements of omega-3 fatty acids are expensive and have not been a part of many of the clinical studies that have been performed to date. Even the largest, best designed clinical study is worthless if the dietary recalls aren’t accurate or people don’t take their capsules.

We need to go back and reevaluate many of the clinical studies that have been published.

We need to ask:

  • Are their conclusions valid?
  • Did some studies fail to show that omega-3s were effective simply because they only measured dietary intake and not how much of the omega-3s actually accumulated in the blood?

The Bottom Line

  • High blood levels of omega-3s in the blood correlated with improved brain health in the elderly and reduced ADHD symptoms in children
  • These studies were small, but they are consistent with a number of other studies that have come to similar conclusions.
  • Blood levels of omega-3s are better predictors than dietary intake for evaluating the health benefits of omega-3 fatty acids.
  • Many previous studies that failed to find an effect of omega-3 fatty acids on brain health, heart health or inflammation did not actually measure blood levels of the omega-3 fatty acids. These studies should be reevaluated.

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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Comments (7)

  • mary cardinale

    |

    Steve,

    Excellent information on brain health/fish oil as it provokes many other questions. Now, what could affect the blood levels of Omega-2 fatty acids in the blood. Obviously, many of the flawed studies assumed that if one consumed say 1200 mg of fish oil that it is a slam dunk. So, what factors could affect the absorption of the oil. How does one make sure that the supplements one consumes results in appropriate levels in the blood! Thanks so much for the umbiased and scientific information; it gives pause for thought about many of the other studies that come out over the media.

    Reply

    • Dr. Steve Chaney

      |

      Dear Mary,

      The problems I was talking about related more to inaccurate recall of omega-3 intake in a diet history, failure to faithfully take the omega-3 capsules, or variable ability for our bodies to convert short chain omega-3 fatty acids such as found in canola or flaxseed oil to the beneficial long chain omega-3 fatty acids such as found in fish oil. There is relatively little evidence for differences in the uptake or utilization of the long chain omega-3 fatty acids in fish oil.

      Dr. Chaney

      Reply

  • Steve Harper

    |

    Great detail and yet comprehensible for the non medically affluent in terminology. Intake versus actual blood content of omega 3 that is a good topic. Makes sense of why some studies say one thing and others just the opposite.
    Great material for thought and study.

    Thanks!

    Reply

  • Victoria Waple

    |

    Question: How does one determine what the Optimal Health blood level should be? Thank You!

    Reply

    • Dr. Steve Chaney

      |

      Dear Victoria,

      We don’t yet have sufficient research to say what the optimal blood level of omega-3s is. Most of the research has been done comparing dietary intake of omega-3s with health outcomes. The authors of the study I quoted were measuring blood levels simply to verify the accuracy of their dietary surveys.

      Dr. Chaney

      Reply

  • Victoria Waple

    |

    Another question: Is it safe to take Shaklee OmegaGuard while on a blood thinner?
    Thanks again for your the valuable infomation in your Health Tip newsletters.

    Reply

    • Dr. Steve Chaney

      |

      Dear Victoria,

      You should consult with your doctor and ask them to monitor your bleeding time so that they can help you achieve the proper balance between onega-3s and blood thinning medication.

      Dr. Chaney

      Reply

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Latest Article

Should We Use Supplements For Cardiovascular Health?

Posted July 10, 2018 by Dr. Steve Chaney

Are You Just Wasting Your Money On Supplements?

Author: Dr. Stephen Chaney

 

supplements for cardiovascular health wast moneyYou’ve seen the headlines. “Recent Study Finds Vitamin and Mineral Supplements Don’t Lower Heart Disease Risk.”  You are being told that supplements are of no benefit to you. They are a waste of money. You should follow a healthy diet instead. Is all of this true?

If I were like most bloggers, I would give you a simple yes or no answer that would be only partially correct. Instead, I am going to put the study behind these headlines into perspective. I am going to give you a deeper understanding of supplementation, so you can make better choices for your health.

 Should we use supplements for cardiovascular health?

In today’s article I will give you a brief overview of the subject. Here are the topics I will cover today:

  • Is this fake news?
  • Did the study ask the right questions?
  • Is this a question of “Garbage In – Garbage Out?
  • Reducing Heart Disease Risk. What you need to know.

All these topics are covered in much more detail (with references) in my book “Slaying The Supplement Myths”, which will be published this fall.

 

How Was This Study Done?

supplements for cardiovascular healthThis study (D.J.A. Jenkins et al, Journal of the American College Of Cardiology, 71: 2540-2584, 2018 ) was a meta-analysis. Simply put, that means the authors combined the results of many previous studies into a single database to increase the statistical power of their conclusions. This study included 127 randomized control trials published between 2012 and December 2017. These were all studies that included supplementation and looked at cardiovascular end points, cancer end points or overall mortality.

Before looking at the results, it is instructive to look at the strengths and weaknesses of the study. Rather than giving you my interpretation, let me summarize what the authors said about strengths and weaknesses of their own study.

The strengths are obvious. Randomized control trials are considered the gold standard of evidence-based medicine, but they have their weaknesses. Here is what the authors said about the limitations of their study:

  • “Randomized control trials are of shorter duration, whereas longer duration studies might be required to fully capture chronic disease risk.”
  • “Dose-response data were not usually available [from the randomized control studies included in their analysis]. However, larger studies would allow the effect of dose to be assessed.”

There are some other limitations of this study, which I will point out below.

Is This Fake News?

supplements for cardiovascular health fake newsWhen I talk about “fake news” I am referring to the headlines, not to the study behind the headlines. The headlines were definitive: “Vitamin and Mineral Supplements Don’t Lower Heart Disease Risk.” However, when you read the study the reality is quite different:

  • In contrast to the negative headlines, the study reported:
    • Folic acid supplementation decreased stroke risk by 20% and overall heart disease risk by 17%.
    • B complex supplements containing folic acid, B6, and B12 decreased stroke risk by 10%.
    • That’s a big deal, but somehow the headlines forgot to mention it.
  • The supplements that had no significant effect on heart disease risk (multivitamins, vitamin D, calcium, and vitamin C) were ones that would not be expected to lower heart disease risk. There was little evidence from previous studies of decreased risk. Furthermore, there is no plausible mechanism for supposing they might decrease heart disease risk.
  • The study did not include vitamin E or omega-3 supplements, which are the ones most likely to prove effective in decreasing heart disease risk when the studies are done properly (see below).

Did The Study Ask The Right Question?

Most of the studies included in this meta-analysis were asking whether a supplement decreased heart disease risk or mortality for everyone. Simply put, the studies started with a group of generally healthy Americans and asked whether supplementation had a significant effect on disease risk for everyone in that population.

That is the wrong question. We should not expect supplementation to benefit everyone equally. Instead, we should be asking who is most likely to benefit from supplementation and design our clinical studies to test whether those people benefit from supplementation.

supplements for cardiovascular health diagramI have created the graphic on the right as a guide to help answer the question of “Who is most likely to benefit from supplementation?”. Let me summarize each of the points using folic acid as the example.

 

Poor Diet: It only makes sense that those people who are deficient in folate from foods are the most likely to benefit from folic acid supplementation. Think about it for a minute. Would you really expect people who are already getting plenty of folate from their diet to obtain additional benefits from folic acid supplementation?

The NIH estimates that around 20% of US women of childbearing age are deficient in folic acid. For other segments of our population, dietary folate insufficiency ranges from 5-10%. Yet, most studies of folic acid supplementation lump everyone together – even though 80-95% of the US population is already getting enough folate through foods, food fortification, and supplementation. It is no wonder most studies fail to find a beneficial effect of folic acid supplementation.

The authors of the meta-analysis I discussed above said that the beneficial effects of folic acid they saw might have been influenced by a very large Chinese study, because a much higher percentage of Chinese are deficient in folic acid. They went on to say that the Chinese study needed to be repeated in this country.

In fact, the US study has already been done. A large study called “The Heart Outcomes Prevention Evaluation (HOPE)” study reported that folic acid supplementation did not reduce heart disease risk in the whole population. However, when the study focused on the subgroup of subjects who were folate-deficient at the beginning of the study, folic acid supplementation significantly decreased their risk of heart attack and cardiovascular death.  This would seem to suggest using supplements for cardiovascular health is a good idea.

Increased Need: There are many factors that increase the need for certain nutrients. However, for the sake of simplicity, let’s only focus on medications. Medications that interfere with folic acid metabolism include anticonvulsants, metformin (used to treat diabetes), methotrexate and sulfasalazine (used to treat severe inflammation), birth control pills, and some diuretics. Use of these medications is not a concern when the diet is adequate. However, when you combine medication use with a folate-deficient diet, health risks are increased and supplementation with folic acid is more likely to be beneficial.

Genetic Predisposition: The best known genetic defect affecting folic acid metabolism is MTHFR. MTHFR deficiency does not mean you have a specific need for methylfolate. However, it does increase your need for folic acid. Again, this is not a concern when the diet is adequate. However, when you combine MTHFR deficiency with a folate-deficient diet, health risks are increased and supplementation with folic acid is more likely to be beneficial. I cover this topic in great detail in my upcoming book, “Slaying The Supplement Myths”. In the meantime, you might wish to view my video, “The Truth About Methyl Folate.”

Diseases: An underlying disease or predisposition to disease often increases the need for one or more nutrients that help reduce disease risk. The best examples of this are two major studies on the effect of vitamin E on heart disease risk in women. Both studies found no effect of vitamin E on heart disease risk in the whole population. However, one study reported that vitamin E reduced heart disease risk in the subgroup of women who were post-menopausal (when the risk of heart disease skyrockets). The other study found that vitamin E reduced heart attack risk in the subgroup of women who had pre-existing heart disease at the beginning of the study.

Finally, if you look at the diagram closely, you will notice a red circle in the middle. When two or three of these factors overlap, that is the “sweet spot” where supplementation is almost certain to make a difference and it may be a good idea to use supplements for cardiovascular health.

Is This A Question Of “Garbage In, Garbage Out”?

supplements for cardiovascular health garbage in outUnfortunately, most clinical studies focus on the “Does everyone benefit from supplementation question?” rather than the “Who benefits from supplementation?” question.

In addition, most clinical studies of supplementation are based on the drug model. They are studying supplementation with a single vitamin or mineral, as if it were a drug. That’s unfortunate, because vitamins and minerals work together synergistically. What we need are more studies of holistic supplementation approaches.

Until these two things change, most supplement studies are doomed to failure. They are doomed to give negative results. In addition, meta-analyses based on these faulty supplement studies will fall victim to what computer programmers refer to as “Garbage In, Garbage Out”. If the data going into the analysis is faulty, the data coming out of the study will be equally faulty. It won’t be worth the paper it is written on. If you are looking for personal guidance on supplementation, this study falls into that category.

 

Should We Use Supplements For Cardiovascular Health?

 

If you want to know whether supplements decrease heart disease risk for everyone, this meta-analysis is clear. Folic acid may decrease the risk of stroke and heart disease. A B complex supplement may decrease the risk of stroke. All the other supplements they included in their analysis did not decrease heart disease risk, but the analysis did not include vitamin E and/or omega-3s.

However, if you want to know whether supplements decrease heart disease risk for you, this study provides no guidance. It did not ask the right questions.

I would be remiss, however, if I failed to point out that we know healthy diets can decrease heart disease risk. In the words of the authors: “The recent science-based report of the U.S. Dietary Guidelines Advisory Committee, also concerned with [heart disease] risk reduction, recommended 3 dietary patterns: 1) a healthy American diet low in saturated fat, trans fat, and meat, but high in fruits and vegetables; 2) a Mediterranean diet; and 3) a vegetarian diet. These diets, with their accompanying recommendations, continue the move towards more plant-based diets…” I cover the effect of diet on heart disease risk in detail in my book, “Slaying The Food Myths”.

 

The Bottom Line

 

You have probably seen the recent headlines proclaiming: “Vitamin and Mineral Supplements Don’t Lower Heart Disease Risk.” The study behind the headlines was a meta-analysis of 127 randomized control trials looking at the effect of supplementation on heart disease risk and mortality.

  • The headlines qualify as “fake news” because:
    • The study found that folic acid decreased stroke and heart disease risk, and B vitamins decreased stroke risk. Somehow the headlines forgot to mention that.
    • The study found that multivitamins, vitamin D, calcium, and vitamin C had no effect on heart disease risk. These are nutrients that were unlikely to decrease heart disease risk to begin with.
    • The study did not include vitamin E and omega-3s. These are nutrients that are likely to decrease heart disease risk when the studies are done properly.
  • The authors of the study stated that a major weakness of their study was that that randomized control studies included in their analysis were short term, whereas longer duration studies might be required to fully capture chronic disease risk.
  • The study behind the headlines is of little use for you as an individual because it asked the wrong question.
  • Most clinical studies focus on the “Does everyone benefit from supplementation question?” That is the wrong question. Instead we need more clinical studies focused on the “Who benefits from supplementation?” question. I discuss that question in more detail in the article above.
  • In addition, most clinical studies of supplementation are based on the drug model. They are studying supplementation with a single vitamin or mineral, as if it were a drug. That’s unfortunate, because vitamins and minerals work together synergistically. What we need are more studies of holistic supplementation approaches.
  • Until these two things change, most supplement studies are doomed to failure. They are doomed to give negative results. In addition, meta-analyses based on these faulty supplement studies will fall victim to what computer programmers refer to as “Garbage In, Garbage Out”. If the data going into the analysis is faulty, the data coming out of the study will be equally faulty. It won’t be worth the paper it is written on. If you are looking for personal guidance on supplementation, this study falls into that category.
  • If you want to know whether supplements decrease heart disease risk for everyone, this study is clear. Folic acid may decrease the risk of stroke and heart disease. A B-complex supplement may decrease the risk of stroke. All the other supplements they included in their analysis did not decrease heart disease risk, but they did not include vitamin E and/or omega-3s in their analysis.
  • If you want to know whether supplements decrease heart disease risk for you, this study provides no guidance. It did not ask the right questions.
  • However, we do know that healthy, plant-based diets can decrease heart disease risk. I cover heart healthy diets in detail in my book, “Slaying The Food Myths.”

 

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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