NOTE: This is the transcript of my YouTube video response, with references.
DR. FUHRMAN: This YouTube video is in response to a series of videos by Jeff Nelson where he promotes his claims about dangers of taking DHA supplement for Vegans, and the worthlessness of doing so to prevent later life dementia.
I had already written an article (The Need for DHA by Vegans (and Near-Vegans) PART 1 published on my blog at DrFuhrman.com in response to his prior videos that discussed this issue and many of his incorrect assertions. My previous, full referenced article challenges the ideas he presented in a manner that I had thought was adequate.
However, since Dr. Klaper, a dear colleague, was featured on Nelson’s video as no longer recommending DHA supplementation, made it evident plant-based consumers may be more confused than ever. I think this is understandable, considering the one-sided information that was presented on this issue by Jeff Nelson. What happened since the filming of that video is that Dr. Klaper has reviewed the studies I am reviewing with you today, revised his thinking, and retracted the statements featured on Jeff Nelson’s video.
These complicated issues are made even more challenging due to the conflicting nature of some studies. The different conclusions of various studies enable people to choose whatever position they want and support it with some evidence.
This idea that whatever the facts show – and whatever I say – is invalid because I sell a DHA supplement is not a legitimate argument. A bias, if one existe, does not change the evidence and the facts. Everyone giving their opinion on this issue is biased, especially the few in the vegan community who have taken a strong stance against DHA supplementation. And especially that I claim they are taking needless risks with people’s later life brain health. That is not an accusation they will readily accept without attempting a robust defense.
I am all for a healthy debate on whether a vegan should take a DHA supplement. But this has not been a civil scientific debate. Jeff Nelson has added an element of character assassination into the debate against me and other leaders in the plant-based movement, which is uncalled for.
So, let’s try to unravel the confusion here.
The first claim made by Nelson, attacking the potential benefit of DHA for brain health, was discussing the lawsuit against CVS, who made a marketing claim that DHA supplements have been proven to improve memory. For some reason, he is associating that claim about improving memory with my assertion that long-standing DHA deficiency can shrink the brain and be a risk factor for developing dementia in later life.
Many observational studies have reported that higher blood levels or intake of omega-3 fatty acids are linked to better cognitive function or prevention of dementia. In the Framingham Heart Study, there was a 47 percent decrease in all-cause dementia in the highest quartile of DHA blood levels.1 This group had an average intake of 180 mg DHA per day, similar to the conservative dose I recommend. In the Rancho Bernardo Study of Healthy Aging, a 73 percent reduced risk of dementia was found for both the top third of DHA intake and a 65% reduced risk associated with the top third of DHA blood levels.2 The report from the Framingham Heart Study was partially industry-funded, but recent meta-analyses of all 21 studies on the subject have confirmed the association between DHA and prevention of cognitive decline and dementia.3 DHA and EPA are important components of brain cell membranes, and it is important to have an adequate supply of these fatty acids throughout life to maintain the health of the brain.
Not only do I not say that DHA can improve memory, but I also say that once you are in your eighties or nineties and have shrunk your brain to the point of dementia from long-standing fatty acid deficiency, and experience memory loss – you cannot regrow your brain and repair your dementia with supplements.
Nelson then criticized me for saying the shrunken brain cannot grow back by presenting a few studies that show that shrinkage of the brain can be slowed with exercise. That, in no way [negates] my assertion that brain shrinkage, to the point of dementia, induced from decades of fatty acid deficiency, cannot be reversed with a supplement used that late point in the disease process. The point I was making by this statement was that if you let a deficiency exist for decades. By the time you note a problem with memory, it will be too late to resolve it; in other words, we need to prevent it, not attempt to treat it later in life.
The fact that this 2012 meta-analysis shows DHA supplementation does not improve cognitive function, supports my assertion that you should not wait until after you develop dementia to think you can supplement with DHA to reverse the condition.4 That’s like waiting until you have lung cancer to quit smoking.
I don’t want those who follow my advice – to eat a vegan diet, or near-vegan diet – to develop any problems due to my guidance. I want to make 100 percent sure nobody is hurt by such advice. I have a responsibility to warn people about the potential risk of DHA deficiency that can happen with a vegan diet.
Am I lying about having patients and vegan friends and mentors develop severe neurologic problems in later life just so I can make money selling a DHA supplement?
Let’s consider that accusation as well. I have been the primary care physician for over 30 years, caring for over 10,000 families including a broad community of vegans and other plant-based health enthusiasts. I think I may have had more experience with caring for elderly vegans and observing their medical issues than any other living physician.
Think about which other doctor advocating a vegan diet has had this much primary care experience treating elderly vegans – who have developed medical issues in their eighties and nineties. What if you were such a physician and had your patients and their families, who you cared about, suffer such a life-altering difficulty from your dietary advice? Wouldn’t you do what you could to make sure these problems don’t happen to you, your family, friends, and those who depended on you for advice. Shouldn’t you share your experience to help others here?
Conventional health organizations and conventional physicians, even those specializing in dementia, typically condone eating animal products, including fish. They have no expertise or experience in caring for elderly, long-term healthy-eating vegans, noting neurological problems and checking their blood work for omega-3 deficiencies. SAD eaters get dementia from their lack of phytonutrients and all the saturated fat and toxic food they consume. Later-life dementia in healthy-eating vegans is a different animal, with an entirely different subset of potential causes, and not an adequately studied phenomenon for them to have a worthwhile opinion on – so their position is meaningless. Especially since they have had no experience with this phenomenon.
In the 1950s – way before the plant-based movement became popular in America, Dr. Herbert Shelton, the founder of the American Natural Hygiene movement, was promoting a plant-based, largely raw food diet to his avid followers, my father included.
We had a connection with a movement of vegans and near-vegans eating a super healthy, whole foods natural diet for many years. I started going to those Natural Hygiene conferences in the early 1970s and became friendly with the leaders, who mostly have now passed away. Over more than 30 years of my medical career, I have cared for many of these long-term vegans, elderly natural hygienists, and some from the American Vegan Society, who ate extremely healthy, took vitamin B12, and generally lived into their nineties.
I am mentioning real names of well-known whole food plant-based health leaders to demonstrate these people and their neurologic problems were real. A significant number of people, including many leaders and doctors in this health movement, developed neurological problems – memory loss and dementia being the most common, like my friend Jerry Deutsch’s mom and Dr. Virginia Vetrano to name a few. But also Parkinson’s Disease, like Dr. Kiki Sidwa and Dr. Herbert Shelton. And my good friend, the famous artist Peter Max, also followed a vegan diet and developed dementia and is still living. When I had the opportunity to check on those patients of mine who had developed these problems, I found the levels of DHA and omega-3 index to be exceptionally low and sometimes even non-existent. Some who are still active in the vegan community do not want me to reveal the names of their parents who developed these same issues. These are not fictional characters, but real people who have suffered greatly. In fact, more of these vegan leaders I knew well, developed neurologic problems than did not.
Of course, it is well accepted that a whole foods, plant-based diet will reduce heart disease and dementia compared to a standard diet, and that taking fish oils or any type of omega-3 supplement on a standard diet won’t help. There are many more contributory causes of dementia besides low DHA, and I expect most people that have dementia do not have DHA deficiency as a cause. However, in healthy-eating vegans that changes, because they are doing so many things right, yet still developed these problems. And, if we can easily prevent this with a simple supplement, we should do so.
In fact, I was motivated to produce a DHA supplement years ago, after observing these problems arising, and there were no vegan DHA-EPA supplements around that did not have high rancidity scores.
Non-supplementing vegans have a broad range of DHA omega-3 index levels: some adequate, many borderline, some marginally deficient, some severely deficient, and some with almost no measurable DHA at all. And this is well documented, at this point. Our non-profit research foundation funded a study on 166 non-supplementing vegans to better understand the percentage with very low measurable omega-3, and the results reinforced my clinical findings. The average omega-3 index was 3.7 percent. A significant number – 64 percent – were below 4, and 27 percent were even below 3, and some were even below 2. Only 9 percent had an omega-3 index greater than 5. And these number did not corelate well with ALA intake; that means eating more flax seeds and walnuts did not fix the problem. Genetic differences in conversion enzyme was found to be the most likely critical factor.5 The scientific consensus is that conversion from ALA to EPA and DHA is limited,6 and according to the Office of Dietary Supplements of the National Institutes of Health: “Consuming EPA and DHA directly from foods and/or dietary supplements is the only practical way to increase levels of these fatty acids in the body.”7
The often-touted notion that the VITAL study proved fish oils are not helpful for protection against heart disease is misleading.
When the details of that study were published earlier this year, it showed that when a subgroup of people who ate little or no fish was analyzed, dramatic benefits were observed. In this study, the 25,871 participants either took a fish oil capsule or placebo, and median follow-up time was 5.3 years. Even though overall there was no significant decrease in cardiovascular risk in the omega-3 group, they found this was because those individuals were already eating fish.
In participants who ate less than 1.5 servings of fish per week, there was a 40 percent reduction in heart attack rate in the omega-3 group. And in participants who ate fish less than once per month, there was a 57 percent reduction in heart attack rate, for those supplementing.8
Large doses of fish oil may have negative health effects – almost any type of supplement can cause harm in excess. However, the fact that excess may cause harm has nothing to do with permitting and condoning deficiencies.
What I would say to those leaders advocating a vegan diet without supplementation is: You’ll gamble with people’s lives and brains and won’t even grant the possibility of low levels increasing risk?
In other words, if you were presented with someone with an omega-3 index below 3, you would not do anything? Below 2? This position cannot be defended – and if you are unsure about your convictions, you check labs and err on the side of caution.
To be absolutely clear, my recommendations,based on a comprehensive review of all the corroborating evidence, is for vegans (and non-fish eaters) to supplement with about 250 mg, which is a low-dose of DHA-EPA – or instead, confirm with a blood test that their omega-3 index is above 5 without supplementation.
Maybe this debate is good, so more people are informed about this critical issue and are not tricked into thinking a low-fat vegan diet without DHA is without risk.
Since the only way to disagree with my findings and the findings of many confirmatory studies is to claim [that] I am lying, and the scientists who run the studies are co-conspirators that have been paid off to fake the results. I don’t care that much about Nelson’s name-calling and trying to smear my character, but the problem is, he is doing that so people won’t believe anything I say, thus the outcome can damage lots of people. Let’s look at the evidence to see who is being honest or dishonest here.
Here is a sample of some of the claims Nelson has made:
So, if you believe Nelson and think I am a liar, criminally faking data and paying off scientists to publish false information to promote my DHA supplements, then I will not likely convince you otherwise, though I sincerely wish I could. I suggest that Nelson is not making careless mistakes, but is intent on destroying my reputation and career. But there is always the possibility he, too, will be influenced by the evidence and decide to remove all the videos with unfair and incorrect accusations and assertions.
One thing we know for sure is that being severely deficient in almost any nutrient causes disease.
And excessive amounts cause disease too, by the way. And I warn against taking high-dose fish oils to drive your omega-3 levels into what may be a high-risk zone. I recommend just a low dose of about 250 mg of total EPA and DHA from an algae-derived supplement. People can overdose with almost any supplement such as vitamin D, iodine, or B6. Too much of certain nutrients can be harmful, but neither should we ignore the problems from deficiencies.
Is DHA some unique substance that it is impossible to have too little of? Is it possible that a deficiency of this important brain nutrient just does not exist on a vegan diet? That is what is being claimed here. There are two studies I know of evaluating brain volume with respect to omega-3 index (a measure of red blood cell EPA and DHA levels) and they are both credible, with many reputable scientists involved and these studies were federally funded, not industry funded.
In the first study there was a threshold effect for brain volume, showing a lower brain volume when then the omega-3 index was lower than 3.9%10 The second study showed a linear association: a 3.2% increase in omega-3 index was associated with a 4.2 centimeter cubed increase in total later life brain volume. A much larger brain volume was reported in quartile 4 with a mean omega-3 index of 7.5% compared to quartile 1 with a mean omega-3 index of 3.4%.11 The KORA study is another important study including 720 participants that demonstrated a 77% increase in cognitive impairment with omega-3 index below 5.7%.12
That’s 3 separate studies all corroborating that a lower omega-3 index is associated with smaller brain volumes or cognitive decline. We can’t say exactly what the ideal omega-3 index would be, but 5 seems a reasonable goal, but clearly it is risky to have a omega-3 index below 4, and that is where about 60 percent of non-supplementing vegans were on the study funded by the Nutritional Research Foundation noted above.13 Only 9 percent of non-supplementing vegans tested in this study had blood levels above 5, which is likely the safest place to be.
Let’s go on to the idea that taking a low-dose DHA supplement can cause prostate cancer and that is why we must avoid this, according to Nelson.
This study appears to be how he first convinced Dr. Klaper to stop taking or recommending DHA. First of all, the study in question did not look at DHA intake, fish intake or algae DHA supplement intake. They only looked at plasma phospholipid levels of omega-3, not the standard acceptable research test. An omega-3 index, because it is a measure taken from red blood cells, is more accurate and reflective of longer-term DHA status.14
Nevertheless, the two blood samples used were not drawn decades before and do not reflect years of omega-3 levels or intake, just likely how much fish they were eating in the days or weeks before their blood was drawn.
Keep in your mind that the major finding in this same study was that low levels of trans fat were associated with more cancer, and the lowest levels were found with more aggressive cancer.15 Trans fat, as you might have heard, is outlawed; it is the most dangerous fat a person can eat, yet this study showed higher amounts in the blood was protective against aggressive prostate cancer. If the results of this study are to be taken seriously, we should be eating margarine and Crisco oil to protect ourselves from prostate cancer.
Remember, cancer causes accumulate for decades before diagnosis. The researchers only had two blood draws, and only the first was drawn before the men knew they had cancer. The second one, drawn a few years later, may have included men who found out they had cancer or had at least noted a rising PSA, so they could have modified their diet as a result.
All we know from this study is that men with more advanced or aggressive prostate cancer ate more fish. Men noting a rising pre-cancerous PSA or prostate cancer typically try to eat healthier, with less meat and more fish. So we don’t really know the significance of this trivial finding that found a very slightly higher plasma omega-3 level in this group with more aggressive cancer. It may be from high fish intake causing a problem, or it may just reflect the timing of the second blood draw. Nevertheless, it has nothing to do with vegans using a small dose of DHA to prevent deficiency.
These results can only make sense if some were informed that they were at heightened risk and then started to eat better, with less trans-fat and less junk food and started to eat more fish instead of red meat. The fact that trans fats were so low in those with aggressive cancer indicates that some men who developed these cancers likely were aware they had some problem brewing. There is no way higher levels of dangerous man-made trans fats could be protecting against prostate cancer, so we know these findings must be a red herring. If we think the findings from this study indicates DHA causes cancer then we should be eating margarine and more potato chips and fried fast food to protect against prostate cancer. Obviously, the findings in this study are meaningless.
Prostate cancer is a slowly growing disease taking decades to manifest and advance to those advanced stages.
If this study reflected an actual effect of omega-3 fatty acids, we would see more prostate cancer in Japan where they eat so much fish throughout life, taking in eight times the amount of fish oils compared to Americans and their DHA levels are double the levels compared to the US. But they have less than a third of the prostate cancer we see here.
If we are considering something so surprising and unlikely that even a low dose of DHA would cause prostate cancer, at least the person presenting that position should review all the studies looking at this question and see where the totality of the evidence points.
A fundamental aspect of quality research is consistency and repeatability.
Reputable studies looking at this question show the opposite: They show higher DHA levels are associated with lower risk of prostate cancer. A recent meta-analysis of fish and prostate cancer showed fish had a protective effect on prostate cancer mortality.16 There are many studies, and the results have not been consistent.17 There are some theories about possible reasons for the increases in risk seen in a few of the studies. It could be the accumulated heavy metals or other pollutants in fish.18 And very high doses of EPA and DHA from fish oil can have an immunosuppressive effect.19 There is also the possibility of detection bias, where health-conscious men are more likely to eat fish or take fish oil and have PSA screening, making a diagnosis of prostate cancer more likely.20
My advice for those eating plant-rich diets has always been to avoid high-dose fish oil supplements and instead take a small dose of vegan EPA-DHA instead. The fact that there may be some small potential risk from high-dose fish oil or from eating lots of fish, has no bearing on the recommendation for non-fish-eaters to take a small insurance dose of algae-derived EPA and DHA to prevent insufficiency and protect brain health with aging.
Dr. Ornish showed his nutritional program reversed prostate cancer – and his program included 3 grams of fish oil supplement a day. The idea that a well-designed vegan diet with just a low dose algae supplement (250 mg) to avoid a deficiency in DHA would cause prostate cancer is not only unsupported, but ludicrous. And, mentioning Dr. Ornish – his recent review of much of this science had him change his prior advice, and now he recommends not only DHA, but also that his heart patients and others consume some nuts and seeds in their diet.
Of course, all of you are free to have your own conclusions and beliefs without being attacked.
Nelson’s attacks on Dr. Greger are also without substance; they are false and devious.
He suggested that I am funding Dr. Greger’s salary or work, so that would make him beholden to me to promote DHA. I think it was about 6 years ago when Dr. Greger was first starting up Nutrition Facts, I donated $1000 to help his website get started. Many thousands have donated money to help Dr. Greger’s noble work, and that wide base of support removes conflict of interest and does not create them. And many scientists serve as advisors for our non-profit research studies, none of them are paid anything. They exist so we can get their opinion on studies to financially support. A smear campaign attacking Dr. Greger is beyond belief, considering Dr. Greger’s authenticity, dedication and being so independent of influence, and being so helpful to many thousands of people. I guess Greger’s major crime (according to Nelson) is agreeing with me. The facts are we both review the science carefully – and have no predetermined agendas to protect.
The profits in my business are not dependent on DHA sales and selling more DHA is not my agenda. Protecting people is my agenda.
Yes, I am saying that Nelson and the very low-fat plant-based colleagues who exclude nuts and seeds, or only allow trivial amounts without DHA, are placing some people at needless increased risk. That does not mean that these individuals have not helped lots of people too, by getting them off their oils, meats and junk food. But I don’t take needless risk lightly, and I am not going to take a chance with the people depending on my advice to even have a small chance of being damaged from such low-fat extremism.
I’m sure this won’t stop them and their loyal followers from denying the preponderance of evidence here. But at least you now know important information to an informed decision about your health. And maybe some of these doctor-gurus will actually be influenced to modify their recommendations with all this hard-to-deny evidence.
What is so ironic is that there is a false concern about a tiny dose of DHA to protect the brain being prostate cancer-causing, when there is irrefutable evidence from numerous corroborating studies showing that diets omitting nuts and seeds and eating so little fat dramatically increase both cardiovascular death and cancer deaths, but that does not seem to be a concern to these low-fat extremists. Correct science always prevails in the long run, as more evidence accumulates.
Wishing you all great health and much happiness.
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