DHA Supplements: A Good Idea, Especially for Older Vegan Men

My October 22 post about Doug Graham’s B12 claims garnered a lot of comments. Among them was one suggesting that I am alarmist at times. So, it is with hesitation that I report the following.

Background: If you are not familiar with omega-3 fatty acids, some of the conversation below might not make much sense. See Omega-3 Fatty Acid Recommendations for Vegetarians for background.

DHA in Elderly Vegan Men

I have been in dialogue with Dr. William Harris about DHA. Dr. Harris has been vegan for many decades and will be 80 years old this December. He has been concerned about making sure he has enough DHA, but in the past when he took DHA, he started bruising very easily. A more recent report from him is that he has been trying DHA again and the bruising has not reappeared.

Dr. Harris cc’d me on a discussion he was having with Dr. Joel Fuhrman and this led me to find out from Dr. Fuhrman that he has been seeing numerous elderly vegans with severe DHA deficiency, and he believes it may have exacerbated Parkinson’s disease and tremors in some of his patients. Upon more questioning, Dr. Furhman had the following to say:

“I have seen thousands of vegan patients, raw foodists, natural hygienists, McDougall and Ornish participants, as well as my own ‘nutritarian clients’ over the last 20 years. I test B12 on everyone, of course we are not talking about B12 [deficiency in regards to the patients with Parkinson’s and tremors], these individuals were well-educated about B12. I have seen some paralysis and other major B12 problems in hygienists and vegan raw foodists. Some that even died from hyperhomocysteine resulting from severe B12 deficiency. I have also seen vegans with balance and ambulation issues with B12 deficiency, unable to walk. One raw foodist who came to see me with this problem, who could not walk, made almost a complete recovery after B12 supplements and then he announced on his radio show that he recovered from M.S. with a raw food diet. ”

“Many of the visits were initiated by complaints. Many people who started or adopted vegan diets went back to eating meat after suffering from fatty acid deficiency symptoms from not eating sufficient seeds and nuts. I have performed fatty acid tests, B12, MMA, amino acid profiles and others on many people. I have seen significant DHA and EPA deficiencies even in middle aged women, but the most predictable pattern is the dramatically low levels in elderly vegan men. I do feel to err on the side of caution, either a blood test to confirm adequacy or a low dose of DHA is indicated, and, as was discussed, you do not need very much [200 – 300 mg DHA per day for one month] to fix the blood test findings.”

Because of the above conversation, I have tweaked my DHA recommendations for vegans, emphasizing that elderly vegans need to take more:

    Under 60 years old: 200 – 300 mg every 2-3 days
    60+ years old, pregnancy, or breastfeeding: 200 – 300 mg per day

This amount may be somewhat more than necessary, but until we know what level can sustain DHA levels long term, it seems like the most prudent amount. This is based both on what Dr. Fuhrman says above, as well as a 2003 study that showed blood levels of DHA to increase 48% in vegans taking 200 mg per day for 3 months (1).

Vegans Convert DHA Better than Fish Eaters

In other DHA news, a study from EPIC-Norfolk recently came out showing that while vegans have lower levels of DHA in their blood, they are more efficient at converting ALA to DHA than people who eat fish (2). This is not surprising, as an abstract by the same lead author was published in 2008 finding the same thing. You can see the EPA and DHA levels in Table 4 of Omega-3 Fatty Acid Recommendations for Vegetarians.

There were only 5 vegan men and 5 vegan women in this study. Despite the higher conversion rate, the vegan men still had significantly lower DHA levels than the fish-eaters. However, the vegan women actually had the highest DHA levels of any diet group (although the standard deviations was quite large indicating that some of the women had very high levels and some had very low). The authors did not address this unusual finding.

Omega-3 Lab Tests

If you are interested in getting your DHA levels tested, Dr. Harris has compiled a list of three labs he was able to find that test them. Dr. Harris was only completely confident in the results from Mayo Clinic.

1. Mayo Labs – $394.60 for 29 different fatty acids including LA, AA, ALA, EPA, and DHA

2. MetaMetrix – $206 for 7 fatty acids

3. Genova – $188.65 for 4 Omega-3 and 6 Omega-6 fatty acids

I am not suggesting that all vegans need to get their DHA levels tested and I do not know anything further about these tests. I am just providing them for people who might be interested.


1. Lloyd-Wright Z, Preston R, Gray R, Key TJA, Sanders TAB. Randomized placebo controlled trial of a daily intake of 200 mg docosahexaenoic acid in vegans. Abstracts of Original Communications. Proceedings of the Nutrition Society 2003:42a. (No link available.)

2. Welch AA, Shakya-Shrestha S, Lentjes MA, Wareham NJ, Khaw KT. Dietary intake and status of n-3 polyunsaturated fatty acids in a population of fish-eating and non-fish-eating meat-eaters, vegetarians, and vegans and the precursor-product ratio of alpha-linolenic acid to long-chain n-3 polyunsaturated fatty acids: results from the EPIC-Norfolk cohort. Am J Clin Nutr. 2010 Nov;92(5):1040-51. Link

25 Responses to “DHA Supplements: A Good Idea, Especially for Older Vegan Men”

  1. Molly Says:

    Received this email from PCRM’s “Breaking Medical News” last week. Posting it not to disagree with you at all, Jack, but just to point out that there is unfortunately still some discord within the medical community.

    Omega-3 Supplement Has No Effect on Alzheimer’s Patients

    Omega-3 supplements do not slow mental decline in Alzheimer’s patients, according to a new study published in the Journal of the American Medical Association. In this trial conducted by the Alzheimer’s Disease Cooperative Study, Alzheimer’s patients who took an omega-3 supplement showed no benefit in cognition or brain atrophy. Researchers randomly assigned 402 participants to either a docosahexaenoic acid (DHA) supplement (2 grams per day) or a placebo for 18 months. Fish oil and other fish products are often touted for their omega-3 fatty acid—specifically DHA—content.

    Quinn JF, Rama R, Thomas RG, et al. Docosahexaenoic acid supplementation and cognitive decline in Alzheimer disease. JAMA. 2010;304:1903-1911.

  2. Jack Norris RD Says:


    Nothing would make me happier than to find out DHA has no positive effects on health. That said, it’s no surprise that DHA showed no benefit for people with Alzheimer’s. I can add more tomorrow.

  3. Jack Norris RD Says:


    There are a number of variables that make the study PCRM describes not relevent to the issue of vegans and severe DHA deficiency.

    Most omnivores have a food source of DHA and have higher levels than vegans. So if Alzheimer’s disease (AD) or Parkinson’s disease (PD) can be caused by severe DHA deficiency, then this will not show up in most omnivores.

    More likely than causing AD or PD, a severe DHA deficiency would present itself with a set of distinct symptoms. Only in the case of a misdiagnosis, where a case of severe DHA deficiency is mistaken for Alzheimer’s or Parkinson’s, would DHA supplementation be able to effect such symptoms, and that is assuming the damage is not permanent.

    That said, if a severe DHA deficiency were exacerbating AD or PD, supplementation could possibly help. According to Dr. Fuhrman, they did not help in the cases he dealt with.

  4. Molly Says:

    Very good information – thank you, Jack! I know I can always rely on you to provide the best, most thorough evaluation of the facts.

  5. beforewisdom Says:

    Hi Jack;

    What sources of DHA do carnists have in their diet? It seems like there are a lot of carnists who don’t eat fish and don’t go out of their way to eat various nuts,seeds.

    About the study you mentioned. Were those 10 vegans regularly eating sources of omega 3s? Were their “low” levels “low” or just “lower” ( than omnis ).

  6. Jack Norris RD Says:


    > What sources of DHA do carnists have in their diet?

    Eggs have some DHA. I just updated Table 4 on the omega-3 page, including the meat-eaters who did not eat fish. Vegans appear to be fine on EPA, having even more than lacto-ovo vegetarians and meat-eaters who don’t eat fish. But meat-eaters who do not eat fish have higher levels of DHA (for men).

    > Were those 10 vegans regularly eating sources of omega 3s?

    Their alpha-linolenic acid intakes were 1.0 g/day for men and .86 g/day for women, indicating that they were not making much of an effort to eat omega-3s.
    The non-vegans’ intake was 1.2 g/day.

    > Were their “low” levels “low” or just “lower” ( than omnis ).

    I have not been able to determine what a healthy level of DHA is. I’m not sure anyone knows.

  7. Ycuk Says:

    Dear Jack,
    I read article http://www.veganhealth.org/articles/omega3 and I have question: how do you calculated n-6/n-3 ratio? Did you use fields “18:3 undifferentiated” and “18:2 undifferentiated” from USDA database considering them as n-3 and n-6? It was difficult to understand that these fields may contain relevant data because in common case it is not so…

  8. Jack Norris RD Says:


    Yes, that is how I calculated it. It is true that those might not all be n3 and n6, but my understanding is that for the most part, that’s what they are. Do you know differently?

  9. Ycuk Says:

    Thanks, Jack!
    No, I see that they are main part now. I may only suggest to add some short notice about it to help understanding. Thank you for your articles and comments.

  10. Jack Norris RD Says:


    Done. Finally.

  11. Sara Says:

    I take a vegan capsule with algae-derived DHA + EPA every day. Since I want to have children in the near future, I don’t want to take any chances with my body’s efficeincy of converting ALA to DHA/EPA. Of course, I also eat flax seed oil, hemp and chia seeds to get ALA.

  12. Sherri Says:

    I was taking a dha only liquid supplement (purchased from Dr. Fuhrman’s site) last year and within just a couple of months my entire body began to bruise. When I would accidentally cut or even nick my skin my blood was actually watery and thin and took forever to clot. I told my doctor and he ordered a lipid panel which showed that my triglycerides were only 30! I immediately stopped the dha and have not taken it since. No brusing now whatsoever and my triglycerides are back up to 50, which is where they’ve been my entire life (I’m 47).I do know that naturally low triglycerides and high hdl (mine is 80) are the rule in my family so am I safe to assume that having such a genetic glitch is indication that dha supplementation is unneccessary? I get very large amounts of ala each day in the form of flax seeds, chia seeds, canola oil, and walnuts and I am vegan.

  13. Jack Norris RD Says:


    Thanks for posting this. How much DHA were you taking?

    Here is the the conversion process:

    ALA → STA → EPA ↔ DPA ↔ DHA

    DHA itself would not cause bleeding (to my knowledge), however too much DPA and EPA can cause bleeding. In your case, it appears that the DPA (and possibly EPA) created by supplementing with DHA is causing more bleeding than any EPA and DPA cause by the ALA (from flax, chia, etc.) in your diet.

    My concern is that you might not be getting enough DHA. I think it would be better to cut back significantly (but not entirely) on the ALA, to prevent EPA and DPA from being made from it, and add very small amounts of DHA (maybe 100 mg every other day). You should talk to your doctor about this first, though, since you have such an unusual situation.

  14. sherri Says:

    Hi Jack,
    Thank you so much for your reply. I was taking 75 mg of liquid dha per day. Your explanation of conversion makes sense and I am considering taking a dha supplement again (perhaps as you say every other day). I will discuss this with my doctor and also cut back on the other omega 3 sources in my diet. I have to admit I’m addicted to hemp seeds and toasted flax seeds on my cereal but maybe it’s time to indulge in a bit less of them. Also I just wanted to say that I use Vegan for Life as my main source of information on vegan nutrition. I have had many books over the years that address nutrition for vegetarians but yours is the most up to date and certainly the most easily understood. Thanks again for your assistance.

  15. Jack Norris RD Says:


    Wow – I cannot believe that only 75 mg of DHA per day could be the tipping point to cause you such problems. Be careful whatever you do. And maybe 50 mg every other day would be a better recommendation now that I know your dose was only 75 mg. I had assumed it was more like 300 mg. What else is in the Furhrman’s oil? Is there DGLA? I see his site is down right now.

    Thanks for the kind words about Vegan For Life!

  16. Sherri Says:

    Sorry, I have to correct myself. The dose was 175mg taken in 0.5 ml dropper once per day. It is pure algae oil with the addition of rosemary extract and a couple of other herbs. I’m sorry my info is sketchy but I no longer have the bottle. Thanks

  17. Jack Norris RD Says:


    Okay, that makes somewhat more sense. Still, 175 mg isn’t that much either…

  18. J Says:

    Speaking of tipping points related to the undesirable bruising effects of flax + DHA supplements, my query pertains to healthy n-6/n-3 ratios and DHA. I’m male, 40, active, vegetarian for the past… 20+ years.

    I’d been supplementing my vegetarian diet with flax oil for the past 2.5 years (1 tsp per day: 1733 mg n-3, 783 mg n-6, 690 mg n-9), no bruising. Last March (2.5 months ago) I reduced the flax by half (1/2 tsp per day: 1034 mg n-3, 201 mg n-6, 340 mg n-9) and added in an algae derived DHA supplement (250 mg per day).

    After two months of flax + DHA I began to notice an unusual level of bruising, many of the the usually minor, forgettable daily bodily bumps that wouldn’t normally show were registering as bruises. Being an avid reader of Jack Norris’ sites (thank you Jack!) I thankfully had a clue as to what was probably going on. I stopped taking the flax and DHA supplements 2 weeks ago and the bruises and bruising have gone. I’m not entirely certain why it took 2 months to reach this point.

    A confounding factor might have been nearly concurrent diet changes, mainly an extremely low level of refined sugars and no refined grains of any kind; a low glycemic-load vegetarian diet. So it’s possible my n-6/n-3 ratio from normal food sources was skewed away from n-6?

    Now the question I’m trying to figure out is what are likely beneficial flax + DHA supplement levels where I gain the benefits while not having blood so thin that easy bruising may occur? 1/4 tsp (1.75ml) of flax per day + 250 mg DHA 2x a week? Thanks!

  19. Jack Norris RD Says:


    Very interesting. DHA is probably not causing the bruising directly but rather after it is converted to EPA (at least, I haven’t seen any evidence that the DHA molecule would be involved). I would wait until your bruising goes down and then add back in as you suggest and see if the bruising comes back. If not, then that should be a good medium to make sure you’re getting enough, but not too much, ALA and DHA.

  20. J Says:

    From your breakdown (posted in above comments):
    ALA → STA → EPA ↔ DPA ↔ DHA.

    If I understand correctly: 1) Excess EPA & DPA levels can cause easy bruising. 2) Both flax oil and DHA are converted/retroconverted to some degree into EPA & DPA. When I supplemented with flax alone there wasn’t enough ALA converted to EPA to create easy bruising. Whereas with flax + DHA there was enough retro/converted to EPA & DPA to cause easy bruising.

    There may be less obvious side effects with excess EPA & DPA levels: http://www.ncbi.nlm.nih.gov/pubmed/16978661

  21. S Says:

    Hi jack

    I used to know u back in my protesting days I’ve now been vegan for about 20 years. I thought everything was fine I look younger than almost anyone my age and such. But suddenly I got symptoms of like a diabetes or PD ….tremors migraines, numb feet and hands it’s very scary. I want to pinpoint any possible deficiency I have so do the above labs have any vitamin and mineral and trace mineral tests one can get ? I couldn’t find it on the mayo site but I emailed them too. Of course my instant fear was my vegan diet ….and the above doctor really scared me so that I considered taking some krill or fish oil and try to stay as vegan as possible and as non harmful to animals (especially the large very sentient mammals) as possible but also get healthy again somehow. However I also know we are easily scared and plenty of non vegans get diabetes and PD and such and we may discover it has nothing to do with dha…OR there may be MULTIPLE causes! The vegan dha may be one, my mind is not closed to that I just want to do whatever I can to help animals and the earth while I stay healthy as possible. Also implicated in many of our diseases I am finding may be the lack of trace minerals in our now deficient soil which could be easily remineralized with ocean or volcanic ash . So I’d love to test my levels on everything!!! Thank you 🙂 ps: I found research that they are shooting cows up with b12 and they are dying due to lack of b12 I believe this is due to a deficiency in the soil of cobalt (which is in ocean minerals) the naturally vegetarian cows are dying of b12 deficiency!! So some kind of scam there maybe. I wondered if you know any vegans who just take ocean minerals and/or cobalt and have not presented with any b12 deficiency

  22. Jack Norris RD Says:

    Hi S,

    It’s good to hear from someone from my past, though I don’t recall who you are. Your symptoms sound very similar to vitamin B12 deficiency. If it were me, I’d get some 1,000 µg cyanocobalamin tablets and take two per day, one in the morning and one in the evening, and chew them (or crush them) before swallowing. Vitamin D deficiency is probably another possibility. I doubt DHA is the problem. If it doesn’t start to improve within 3 days of taking the B12, you should definitely see a doctor (if not before then).

  23. S Says:

    Hi jack thanks ! It’s not that, I am very aware of b12

    I was anemic and upped my b 12 years ago

    But I’m learning all these diseases: ms, Parkinson’s, fibroglymania, ALS, diabetes, and more all have the same symptoms . To me they sound like the same disease. I researched it and the common link is Lyme disease. We may have a plague of Lyme disease in our country (not joking) and efforts should be put on curing this hard to kill bacteria rather than blaming our diets. I’m just saying its a possibility. I’m still not sure on the dha link perhaps the doctor above could be asked if the omegas ever cured Lyme in his opinion….Lyme is EXTREMLY misdiagnosed as Parkinson’s and more! Thanks!!!! *investigation of medical fraud*

  24. SS Says:

    Hi Jack,
    I just started reading your excellent and very informative website yesterday. I’m a long time ethical vegan 60 years old that has had some health problems that this year that have gotten much worse. In February I started having dry eye syndrome and couldn’t find any natural overnight ointment so I have been using Systane. I have stomach digestion problems and have had 4 or 5 upper and lower G.I. tests in my 30s and 40s. They couldn’t find anything and said I have a nervous stomach! Unfortunately having a stressful job I developed diarrhea (or close to it) almost every day. Because of this I started eating more and more processed foods, because cooked vegetables and fruit makes my condition much worse. Then a couple years ago I have lived almost entirely on this terrible diet relying on vitamins. Late last year I started to take Black Seed oil and this helped tremendously. Now I’m consuming 16 ounces a week because it’s effect is lessening greatly. Also I’m taking daily 2 probiotics veg caps that help quite a bit. I am thoroughly confused about omega 3, 6 & 9’s role in health and ratio because of all the vastly different opinions. Does ALA becomes EPA then DHA in the body? I would love to follow vegan nutritionalists recommendation to NOT use supplements and get all the nutrition needed from a plant-based diet. But with my current state of low energy and health problems what would you recommend?

    Thank you for all your time and compassionate help.

  25. Jack Norris RD Says:


    I’m very sorry to hear about your digestive problems. You might find some of these articles helpful:


    Here are my recommendations for vegans in general:


    I don’t think they would change much due to your condition.

    > Does ALA becomes EPA then DHA in the body?

    Yes, but the conversion all the way to DHA isn’t terribly efficient and is why I recommend a modest supplement to be prudent.

    I hope that helps and good luck!

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