Claire Corlett

Fish Food, Fish Tanks, and More
Should Vegans Take DHA to Preserve Brain Function?

Should Vegans Take DHA to Preserve Brain Function?

“Should Vegans Take DHA
to Preserve Brain Function?” We are all fatheads. About a half of the dry
weight of our brain is fat. Lower levels of the long-chain
omega 3 fat, DHA, in some areas of
Alzheimer’s brains got people thinking that
maybe DHA was protective. Since the level of DHA in
the brain tends to correlate with the level of
DHA in the blood, one can do cross-sectional studies
of dementia and pre-dementia patients, and they do tend to have lower levels of both
long-chain omega 3’s, EPA and DHA, circulating in their bloodstream. Now this doesn’t necessarily
mean that lower omega 3 levels cause cognitive impairment. It was just a snapshot in time, so
you don’t know which came first. Maybe the dementia led
to a dietary deficiency, rather than a dietary deficiency
leading to dementia. What you want is to measure long-chain
omega-3 levels at the beginning and then follow people over time, and indeed there may be
a slower rate of cognitive decline in those that start out
with higher levels. And you can actually see
the difference on MRI. Thousands of older men and
women had their levels checked and were scanned
and then re-scanned, and the brains of those with higher levels
looked noticeably healthier 5 years later. The size of our brain actually shrinks
as we get older, starting around age 20. Between ages 16 and 80 our brain
loses about 1% of its volume every two to three years,
such that by the time we’re in our 70’s,
our brain has lost 26% of its size, and ends up smaller
than that of 2 to 3 year old children. As we age, our ability to make the
long chain omega 3s like DHA from the short chain omega 3s in
plant foods such as flaxseeds, chia seeds, walnuts,
and greens may decline. And so researchers compared
DHA levels to brain volumes in the Framingham study and
lower DHA levels were associated with smaller brain volumes, but
this was just from a snapshot in time, until this study was published. Higher EPA and DHA levels correlated
with larger brain volume eight years later. While normal aging results
in overall brain shrinkage, having lower long-chain omega-3’s
may signal increased risk. The only thing one would need
now to prove cause and effect is a randomized controlled trial showing
we can actually slow brain loss by giving people extra
long-chain omega 3’s, but the trials to date showed no cognitive
benefits from supplementation until now. Double-blind randomized interventional
study providing evidence for the first-time that extra long chain
omega 3’s exert positive effects on brain functions in
healthy older adults, a significant improvement in executive
function after six and a half months of supplementation, and significantly less
brain shrinkage compared to placebo. This kind of gray matter
shrinkage in the placebo might be considered just
normal brain aging, but it was significantly slowed
in the supplementation group. They also described changes
in the white matter of the brain, increased fractional anisotropy, and
decreases in mean and radial diffusivity— terms I’ve never heard of, but evidently
they imply greater structural integrity. So having sufficient long-chain
omega 3’s, EPA and DHA, may be important for preserving
brain function and structure. The next question becomes what’s
sufficient, and how do you get there? The Framingham study found
what appears to be a threshold value around an omega 3 index of 4.4, which
is a measure of our EPA and DHA levels. Having more or much more
than 4.4 didn’t seem to matter, but having less was associated
with accelerated brain loss, equivalent to like an extra
two years of brain aging. That comes out to be about
a teaspoon less brain matter, so it’s probably good to have
an omega 3 index over 4.4. The problem is that people who
don’t eat fish may be under 4.4. Nearly two-thirds of vegans
may fall below 4, suggesting a substantial
number of vegans have an omega-3 status associated
with accelerated brain aging. The average American just exceeds the
threshold at about 4.5, though if your age and gender match for the vegans,
ironically the omnivores did just as bad— there’s not a lot of long-chains
in Big Macs either. But having a nutrient
status no worse than those eating a standard
American diet is not saying much. All we need now is a study that gives
those with such low levels some pollutant-free EPA and DHA
and see how much it takes to push people past the
threshold, and here we go. They took those eating
vegan with levels under 4, gave them algae-derived
EPA and DHA, and about 250 mg a day took
them from an average of 3.1 over the line to 4.8
within four months. And so that’s why I recommend
everyone eat a plant-based diet along with contaminant-free
EPA and DHA to get the best of both worlds:
omega 3 levels associated with brain preservation while
minimizing exposure to toxic pollutants.

100 comments on “Should Vegans Take DHA to Preserve Brain Function?

  1. Dr. Greger, every day I eat about: 1 table spoon of milled flax seeds (kept air tight in a freezer), 1 table soon of chia seeds, 1/2 cup of assorted nuts (almonds, walnuts, pecans, cashews), and about 7 pumpkin seeds. I understand this is all considered short chain Omega 3. I understand that my body will convert some of this to long chain Omega 3. Given that I eat all this short chain Omega 3every day, how much algal oil should I take daily?

    Also, other doctors have told my wife, who is nursing our daughter, that anything with algal oil is dangerous for her to have. What do you think about that?

  2. The only problem with this is that moving from contaminated fish to contaminated supplements isn't really an improvement. There's is zero regulation of vitamins and supplements in the U.S. and independent analysis done by Consumer Reports consistently finds higher than safe levels of arsenic, lead, cyanide, etc. and often much less if any of the stated ingredients.

  3. I need HELPPPPP!!! I'm in a nutritional dilemma!! I'm 5'11 130 lbs and trying to gain weight on a vegan diet. The best and easiest way for me to gain is to eat a ton of peanuts, cashews, and almonds. However, doing this throws my Omega 6:3 ratio out of wack (so much Omega 6 in nuts)! Is this okay considering the main source of Omega 6 is whole foods or must I change something???

  4. So gorillas don't need DHA? I know they just eat leaves and stems. First b-12 we need, then iodine now DHA, Been a vegan 8 years, maybe I'm doing the wrong thing. Evidence is showing maybe we supposed to be eating fish. I don't care to spend my money on factory made pills.

  5. Awesome video!!! Helped me soooo much! I was in doubt as to should I keep taking my EPA DHA algae omega or not. Thank you.

  6. Question! Hopefully somebody will respond. I have been taking 2 Nordic Naturals Algae Omega Soft Gels each day for the past 2 months (as long as I've been vegan). The amounts per serving (2 gels) are:
    Total Omega-3s: 715mg
    EPA: 195mg
    DHA: 390mg
    Other Omega-3s: 130mg

    Given these amounts, do I need to take 2 every day? Can I take 1 per day or two every other day? Does the 250mg of L-C O3FA's mean any as long as the total is 250mg?

    I appreciate the input.

  7. The conversion of the plant-based omega-3 ALA to the long-chain EPA and DHA may be increased in vegans and vegetarians who do not eat fish, suggest results from the European Prospective Investigation into Cancer and Nutrition (EPIC).
    Omega-3: ALA intakes enough for EPA/DPA levels for non-fish eaters?
    By Stephen Daniells, 08-Nov-2010

  8. Despite the more efficient delivery of DHA from algal derived DHA than conversion of ALA from flax seed, I still prefer the flax seed as it seems less likely to be adulterated than processed algal inserted into capsules. Could be wrong of course.

  9. I been taking 10-20 grams of hemp/chia or flax seeds 4-5 days a week for 5+ years and i feel great. My mind is actually much sharper now than its been when i was eating meat, fish, dairy and wheat.

  10. Where is the evidence that short chain omega 3s are ineffective? Vegans may have lower DHA and EPA, but how many vegans have a steady and abundant daily intake of walnuts and flaxseed? If you can show me that such vegans have low DHA only then will I be convinced.

  11. There needs to be a method of planning to ensure people consume what's needed. Counting macro nutrients won't do it. And that's hard enough to do. Everyone should eat 250 mg of pollutant free long chain omegas to protect brain function. That's pretty important. Along with everything else he says. If we don't have a structure that supports implementation (similar to counting macros) no one will do it and then what good is all this doing?

  12. Is it enough to eat wakame and nori on a regular basis? In your book you recommend algea omega 3 supplement. You only mention eating algae regarding iodine intake.

  13. Your channel is great, but please learn how to use a microphone. It clips in nearly all of your videos. Clipping is when the audio signal is greater than what your recording medium can handle and so results in an unpleasant distorted sound. Turn input levels down a bit and compress audio after recording if you want it to be an even loudness.

  14. Controls 3.5% were US soldiers in Iraq??? That's not a good gender and age match …just sayin. Have you seen what soldiers get fed ?


    Generally, none, although we suggest that you consult with your physician before taking our fish oils if you are allergic to iodine."

    Obviously, at least Nordic Naturals contains iodine, even after extensive purification and molecular distillation. What if the effect is actually from the iodine, not the fish oil? After all, iodine is definitely associated with intelligence and brain function. The absolute #1 factor in low IQ is lack of sufficient iodine in prenatal diet. AND high IQ is associated with high prenatal iodine diet as in Japanese.

  16. I don't want to supplement. Where's the study for using flax to raise low levels? He mentioned that ALA conversion rates worsen as we age, but couldn't we just eat a little more of it?

  17. Its a good idea to take a vegan omega 3 supplement, when I went vegan at first I felt great, and I was taking 4 tablespoons of ground flax every day for my omega 3, but several months down the road I had severe stress and depression, so I bought vegan omega 3, and as soon as I took the dose within hours my stress and depression went away, and I was feeling mentally great, some people just cant convert ALA to DHA., even young people like me, at 22.

  18. It seems unreasonable that vegans who consume plenty of ALA should supplement with EPA. It would be nice to know how much DHA is beneficial provided sufficient ALA and EPA.

    In the final study highlighted in the video, participants went from below 3 to 4.8 within four months. One might expect levels to continue going up. What is a reasonable dose to maintenance 4.4? What units?

  19. Interesting, another Nutrient Vegans need to supplement. Add it to the list containing: Vitamin K2, Vitamin B12.
    Any more we need to know about?

  20. I found this vegan omega 3 from algae.  Does it do what we need?

  21. I recently watched all the Omega 3 series on NutrionFacts. This one gives you the only reason to supplement Long chain Omega 3. But IMO, unless you are strict Vegan for ethical reason, you can just get your Long Chain Omega 3 from one single fish oil capsule/day to save a lot of money. Yes there are some trace PCBs, but it's an infinitesimal amount compared to what you would get eating a serving of fish, or any animal product. If you eat a plant based diet and take 1 fish oil capsule, your PCB exposure will be MUCH lower than the general population. Dr Greger, is too alarmist about PCB content of a single capsule without backing it with any kind of scientific info, like he does for mercury in Tuna.

    I'll never eat Tuna again, but to switch from fish oil to ultra expensive algae sourced, I need to see some science, not alarmist rhetoric.

  22. Mate, I have to say, that was the best video I think I've watched all year. Absolutely bang on, in terms of coherence, references, and just all in all enjoyable to watch. Thank you so much for your efforts and enlightening me on the topic, now I'm off to buy some algae based omega 3s!

  23. His answer is YES.I have been taking a plant-based omega DHA/EPA from JUICE PLUS+ which is great for brain function as well as anti-inflammatory. The algae is grow in a protected farm in Hawaii.

  24. In the video, you say 250+mg of EPA/DHA, but what are the ratios to look for? There are many different ratios of EPA/DHA in the brands I'm looking at, so blanketing both supplements together in a recommendation is really throwing me off! Confusion aside, your videos are great! Keep up the good work.

  25. There is a home test kit available on to find if your level of Omega-3 is above the 4.4 mark mentioned in this video. So, instead of buying expensive algae oil supplements, I bought the test first to see if I need the supplements- I take two tablespoons of ground flax seed most days. I scored 4.9 and my lady friend got 5.1. No need for either of us to supplement. But not everyone who eats flax regularly should assume that they're okay. Could be that some people don't convert ALA to DHA very well. In fact, I plan on retesting every 10 years or so to see if my ability diminishes with age.

  26. Keyword 'may' that's how all scientists cover their asses.
    May do this, may do that, may help, may screw you.

  27. THIS IS WHAT WAS WRONG WITH ME. I’ve had so many problems after I went plant based: I had dandruff all my life even before I was vegan: I’ve always felt likenshit. My hair was horrible. Blood pressure was high and i ate flax seeds everyday! I took an algae supplement and I felt better in like less than twenty minutes

  28. there is theory that when you consume DHA that supresses the enzime that converts ALA to DHA and EPA…/ahiflower-oil-how-it...
    what is your opinion about that?

  29. Thank you very much for ending this debate! I'm young but my parents are 50 and eat plant based so I'll definitely get supplements for them!

  30. The trial had a much higher dose, over 2 grams combined EPA+DHA. The lower dose you recommend is not backed up by the trial.

  31. I'm lost. Meat seems to cause cancer, heart disease etc. Vegan diet is unsustainable without supplementing B12, zinc, iodine, vitamin D2…..
    What am I supposed to eat? Seems like whatever I do will cause some problem.

  32. For those of us that can't afford such a supplement (which would include my husband and I, as my husband is on disability), just eat freshly ground flax seeds. Your body can convert ALA to DHA and EPA, so if you eat enough, you can get enough of all three (whereas sea vegetables cannot supply you with ALA at all). If you're worried that your ability to convert ALA is impaired for some reason, just be generous with the flax seeds. My husband and I take 3-3.5 tablespoons a day. Some recommend as much as 4-5 tablespoons. Since the research shown in this video demonstrates no negative effects from going over the 4.4 threshold, might as well eat as many as you can afford. Even the amount we eat is far less expensive than algae oil, and provides other nutrients besides. 🙂

  33. Nowhere does he mention oil – He just recommends a 250 mg DHA and EPA supplement, is there an oil free version of this?

  34. Ive been taking vegan algae based oil gelcaps. They are horrible. They stink. They taste aweful and the fish burbs n quesy stomach is exactly like horrible ol fish oil.

  35. The control for the study talking about the EPA and DHA of, in your words, the average American diet vs that of a vegan is actually US soldiers deployed in Iraq. I suspect that their diet is actually quite different (for better or worse) than the average American.

  36. Personally I have just kept up with taking krill oil while vegan. I guess call me plant based or whatever. Astaxanthin has a lot of benefits and it’s a good source of phosphatidyl choline and DHA. Not sure how many vegans would put krill in the sentient cognizant animal category.

  37. Even your vegan master guru says you must take dha epa supplements and some of you guys keep saying noooooo you're fine b eating flaxseeds. What a bunch of brainwashed fools you vegans are. Ridiculous!

  38. Frankly, there are a lot of places where Dr. Greger weighs in on O3s and here he says he recommends them, but in other places he says they are worthless. The sad fact is, as he notes here and as is noted all over the place about B12, you can recommend all you want, if a diet is producing 70+% or more people with shrunken brains, it's got some obvious real world downsides that should be addressed since the recommendations are not working.

  39. Does algae-derived omega 3 contain the neurotoxin BMAA (found in blue-green algae and linked to ALS, Alzheimer's)?

  40. Sardines on Sunday for me. 1190mg of 3, for 4 oz. Being tiny fish, wild sardines have not been around long enough to become toxic. plus flax meal daily.

  41. Idk… I avoid the supplement aisle because it's an unregulated money pit. But I'll try to remember this one if I become pregnant and/or old.

  42. how does it fit into the "no oil"-strategy? All supplements, i found so far, are oil-based. are there alternatives?

  43. Watch out there are researches that showed omega 3 supplement has no benefit or worse can cause prostate cancer. Can Dr Gregor willing to discuss about it? I bet NOT. Please read yourself other many available studies before ordering omega 3 supplement.

  44. What’s the bottom line please? Do I need to supplement or not? As a vegan I take 2 tablespoons of mixed ground flax and chia daily 🌟

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