Doctor's Note

Maybe the ice bucket challenge should be to not serve seafood in them. The story continues in my next video: Diet and Amyotrophic Lateral Sclerosis (ALS).

Diet may also play a role in other neurodegenerative disorders:

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  • Alex

    Spirulina (athrospira ..) wasn’t mentioned in the tests. Curious omission?

    • Julie

      Almost all blue green algae, including spirulina, can produce neurotoxins like BMAA. Not sure how much BMAA, but enough for Dr. Greger to recommend that we stay away from spirulina.

      • Alex

        I had understood that spirulina itself did not contain toxins (microcystins, BMAA, etc) but that other algae harvested alongside likely would.

    • sf_jeff

      I am wondering if this new information actually makes blue green algae look better because at least its BMAA hasn’t been bio-amplified.

    • Darryl

      McCarron P et al 2014. Analysis of β-N-methylamino-L-alanine (BMAA) in spirulina-containing supplements by liquid chromatography-tandem mass spectrometry

      In the current work, we have analyzed ten spirulina-containing samples for the presence of BMAA; six pure spirulina samples from two separate raw materials suppliers, and four commercially-available multi-ingredient products containing 1.45 g of spirulina per 8.5 g serving… BMAA was not detected at low limits of detection (80 ng/g dry weight) in any of these product samples.

      • e

        many thanks for posting this–I take spirulina tabs each day, and would not like to give them up–this research is reassuring

        • Alex

          Yeah, but that’s just BMAA. There may be microcystins and heavy metals which have been found in commercially-available products. The Doc’s suggestion is “it’s not worth the chance”.

          • shrillthrill

            Heavy metals don’t appear to be a concern in reputable brands (many of which do their own testing), see this study which tested 25 brands of spirulina:

          • elsie blanche

            What do you think about eating nori and other seaweeds? This concern you regarding BMAA or other microcystins/metals?

    • zm4jk0

      What aboult chlorela, kelp?

    • Zack Barkley

      Pretty much all cyanobacteria produce BMAA, so probably spirulina has it too. The interesting thing however is that it is a very very low amount. Accoding to a PNAS paper, the BMAA is concentrated over many thousand fold in some cycads and fish and bat brains which live in symbosis or consume large quantities or are futher up the food chain. It seems humans probably can tolerate the spirulina dose although if it is highly concentrated in animals up the food chain, that is more questionable. BMAA is definitely a neurotoxin. Whether the doses regularly consumed by humans are significant is an open question. There are plenty of other toxins in our environment, some of which induce Parkinsonism is extremely low quantities in lab animals…like the pesticide rotenone. The motor neurons and brainstem neurons that are effected in ALS and Parkinsonism are huge and metabolic power-houses which fire very rapidly and continuously (unlikely the slower firing neurons in the cortex). It is probably why they are so sensitive to environmental toxicities. Twin studies also support that most cauaes are Parkinsonism are environmental as well.

  • Ellen Lederman

    So what about taking algae pills since as a vegan I don’t eat fish/take fish oil for the omegas?

    • Arjan den Hollander.

      It doesn’t seem to be lipophilic so unlikely to accumulate in oils.

      • Dasaniyum

        So does that mean fish oils wouldn’t have significant levels of BMAA either?

      • Alex

        Good question, Ellen. Since as a fellow sentient being abstaining from Hg, DDT, and PCB I don’t take fish either. :)

        Arjan, that’s very interesting. “since BMAA is not lipophilic but water soluble, its biomagnification pathway must differ from that of the lipophilic agents” ( several sources: ). Though, I’d still sleep better at night with testing of all known/likely neurotoxins. It’s amazing to me that ‘supplements’ being neither foods nor drugs (right!?) are unregulated and poorly tested.

    • Ravi K

      There are many plant based sources for the Omegas. I use the Udo’s 3-6-9 Blend.

    • Gar Zuzik

      Great question: I speculate that the homocysteinemia resulting from not ingesting b12-rich sources would present a more acute and sever threat.

      I am a vegan that chooses healthier selections and also avoids high-methionine rich sources and also soy lecithin, but I ingest a normal b12 supplement from ‘nature made” or whatever is cheap and a good texture ect… due the minimal concentration of whatever I fixated on in the past (gellatin).
      (one does not want to become Orthorexic lol)

      • Alex

        Most “natural” vegan B12 is not bioavailable (aka analogues and snake oil).

        • jsarrick

          Could you explain what you mean here? Thanks!

          • Alex


            An analogue looks like a duck and quacks like a duck but may not in fact be a duck.


            One part of [B12 is the] corrin nucleus, which holds an atom of cobalt… The corrin plus other atoms make up the cobalamin part of B12… Only two cobalamins are active as coenzymes in the human body: adenosylcobalamin and methylcobalamin. The body has the ability to convert [other cobalamins such as] cyanocobalamin… Many corrinoids, and possibly even some cobalamins, are not useable by human B12 enzymes. These are considered inactive B12 analogues.

            Inactive Analogues: Worse than Useless — Carmel et al. (1988) “Patients with primarily neurological problems had significantly higher inactive B12 analogue levels… Some B12 analogues may be harmful to the nervous system.”


            Unlike animals, most, if not all, plants have no B12 requirement for any function, and therefore have no active mechanisms to produce or store B12… B12 activity actually decreased in people fed a combination of spirulina and nori. [and dozens of other studies demonstrating inactive B12 from plants, algae, and fermented foods].


            I didn’t realise “Nature Made” was a brand name. One of their tablets contains 1 mg (1000 mcg) of cyanocobalamin which is fine bioactive B12.

          • Fruitopia

            The study that showed nori reduced b12 levels had only 12 subjects; 3 of these peoples’ b12 levels rose and one person whose levels fell had abnormally high b12 levels to start with, so IMO should have been excluded from the study. This study is too small and inconclusive to declare absolutely that the b12 found in seaweed is unavailable. I could just as easily post other studies showing that seaweed is a good source of b12.

            The bottom line is that a) more study is needed, and b) almost everybody should take a sublimgual b12 supplement, as the b12 in animal products has very low absorption, and it is not conclusive that the b12 in non-animal products is bio-available.

          • Alex

            A study with insignificant results (n=12) does not make the contra-position true. One can find numerous studies demonstrating B12 analogues in sea plants and algae, but as of 2015, I do not believe any study has found significant *bioavailable* B12 from sea plants or algae. To assume nori, fermented plants, or spirulina has bioactive B12 is, if long-term, a dangerous experiment (n=1) with potentially permanent negative neurological consequences on the test subject.

        • Fruitopia

          All vitamin b12, whether “natural” or created for supplements, is synthesised from bacteria. The vast majority of b12 supplements are made from bacteria from rice. But some specialist supplements source b12 from soil bacteria. I think this is what he was referring to.

      • Fruitopia

        Why? The bioavailability of b12 from red meat is just 0.1%. Nearly 4/10 non-elderly meat eaters have low b12 (rising to nearly three-quarters of the elderly), and nearly 1/10 have an outright deficiency. Consuming “b12 rich sources” to get b12 is unreliable at best, and not worth the risk to one’s health, the environmental destruction, and the animal abuse.

        I am sick of the obsessing over b12. For the majority of nutrients, we fare much better than meat eaters, so it is just propaganda and discrimination that everyone focuses on problem that affects many meat eaters. Everyone should take sublingual methyl- and adenosyl-cobalamin supplements, regardless of diet.

        Besides, it is a problem of modernity: unchlorinated fresh water from lakes and rivers contains so much b12 that the amount accidentally swallowed while bathing provides enough b12 for a whole week. Because our natural source has been lost to most of us, humans need to take a b12 supplement.

        • Alex

          It is true that B12 deficiency exists across all populations and diets and that the elderly have lower absorption of B12. It is also true that some meat shrills like to harp on the “vegans can’t get B12 from plants” fact as a reason to dismiss the vegan diet all together. However, more damaging to our cause than meat shrills are the disproportionally higher number of vegans who fail to obtain adequate B12. Yes, all vegans should take B12 supplements or fortified foods and not become another stupid vegan statistic or headline.

          • jeanie

            I’ve known eaters-of-red meat with LOW serum B12levels. Don’t guess, TEST!
            Just taking a high-quality supplement does NOT guarantee adequate absorption of B12 for anyone.
            I took Thorne brand B12 for a year; and after a blood test, I still needed intra-muscular injections of methylcobalamin, which finally corrected the anemia I had. I’m not vegan, I do eat some eggs, & rarely seafood.

          • Alex

            It’s a matter of degree and risk. Studies have shown B12 deficiency in 10% of the general population, 40% in those above sixty years, and 80% of all vegans. Test if you have reason to be concerned, but understand that the vast majority of the population responds well to cyanocobalamin supplementation, while other forms (hydroxo- and methyl-) may be more appropriate for those already deficient or who have an issue with absorption.

            Meat eaters are NOT guaranteed (80%) to become B12 deficient without supplementation.

          • Shayna Teicher

            So true Jeanie! Supplements aren’t always as simple that we’d like to think. :)

        • Vaughan Elphick

          Just drink coffee with a B12 supplement. It increases absorption. Thing is it decreases most of the others so at least allow 2 hours after you drink a coffee or any other caffeine to have your other multi if you take one.

    • Bruce Cropley

      I have a tablespoon of ground flaxseed (=linseed) on my muesli for the Omega 3 content (daily). I think that is what the experts here recommend. :)

      • Alex

        Sorry, commented below… Experts also suggest 100-300 mg DHA daily from algae (see below).

        • Vaughan Elphick

          Depends which experts. I’ve read DHA is pretty useless apart from you are a child. The assumption was made because there is a lot of DHA in the brain. Thing is EPA is a better anti-inflammatory and they both compete with each other. Also EPA shines a lot better in most studies (depression elevation, anti cancer, although so does DHA there, and neurological benefits).

          Plus EPA is converted to DHA a lot easier than the other way around if the body needs it.

          I’ve personally experimented with both and Pure EPA works the best heads and shoulders above for anti inflammatory / pain reduction and as an anti depressant and study aid.

    • tbatts666

      I would second comments about flax seed. I think it’s high in the omegas. Remember to grind it (Or buy it ground). I get mine on amazong, but most big grocery stores have flax in the baking section. Costco too.

      Works really great in stews and oatmeal and stuff.

      • Alex

        Ground flax (and chia) provide a large dose of ALA (essential omega-3). About 7% may be converted to EPA and a much smaller percentage again may be converted to DHA. Thus it’s reasonable to assume a strict vegan (and non-fish eaters) will not have adequate DHA even with a rich ALA source such as flax.

        Many experts (Dr Greger, Norris RD, Messina MPH-RD, Fuhrman) suggest 100-300 mg DHA daily from algae for vegans or those concerned about fish consumption.

  • Kirti Shah

    what about Omega from Algae source – do they also contain BMAA

    • Joevegan

      Sounds like a good question for the NF Research Fund.

      • Alex

        I vaguely understood that bluegreen algae (Cyanobacteria phylum) are of concern, while DHA producing microalgae are in the Myzozoa and Heterokontophyta phyla. EPA is sourced from various algae some of which are also in the Heterokontophyta phylum.

    • george

      Blue green algae and algae are not the same thing. Blue green algae are a subclass (may not be the correct biological term) of bacteria.

      • Alex

        Close enough. :) Class is more specific than phyla.

        Domain: Bacteria
        Kingdom: Eubacteria
        Phylum: Cyanobacteria

        Algae are in the Eukaryota domain.

    • Frankie

      Red algae contains kainate, a neurotoxin that can cause epilepsy. We also get long-chain omega-3’s from a red algae. I hope the pill we’re taking are purified from this nasty stuff.

    • Joseph Gonzales R.D.
      • Karen Harris

        Would this be considered safe from BMAA?

        • Joseph Gonzales R.D.

          Yes, golden algae doesn’t appear to contain BMAA and would be considered safe.

          • Freya Nielsen

            Makes me nervous that you say “doesn’t appear to contain BMAA”. The tank grown algae in Udo’s blend, is that sure thing? They say it contains “no ocean borne contaminants”

          • Joseph Gonzales R.D.

            I know what you mean I just cannot guarantee anything until it’s tested. Have you seen my post on it? I put a link above to Karen. I mention how you could get DHA form yeast, too. And note that DHA is not a required nutrient so you do not have to take any supplement if you don’t think it’s best. If you do choose to take it, I’d rather take my chances with algae over fish oil based on the research we do have.

        • Joseph Gonzales R.D.

          Hi Karen. Yes, it does appear safe. Check out my additional post about this here, if interested.

  • Sebastian Tristan

    Very interesting. However one question is imperative: since fish and seafood consumption is so widespread, why don’t people in the US and Canada, for instance, have the same rate of ALS and Parkinson’s similar to the inhabitants of Guam?

  • Susan Nevins

    Dr Greger..please clarify what type of algae/seafood we should avoid spirulina? OMEGA oils from Algae?…please offer some advice on this topic..Im sure we would all like to know…Thanks

    • Janie

      These were my exact question too. Would be nice to have further clarification on this topic.

    • Linda

      What fish should we avoid eating and should we stop taking fish oil supplements?

      • Alex

        All. Yes.

        All (some fish are worse than others). Yes (majority of fish oils are rancid before leaving the factory, nearly all contain toxins, very few are thoroughly tested with results published.).

        • Bill Coe

          Alex…I take “pharmaceutical grade” fish oil, prescribed by my doctor and sent to me by my insurance company. Is that product safe?

          • Alex

            Hi Bill, I certainly cannot say whether any specific product is safe. I have no idea. “Pharm grade” sounds like high quality stuff. Perhaps you could ask for test results.

    • Joseph Gonzales R.D.

      HI Susan. Super important questions thanks for asking. Golden algae is different from blue-green algae. Please note this sight is flooded with great information and most can be found by clicking the “HEATH TOPICS” button at the top of the screen :-) Here is a video talking about golden algae. And several videos on spirulina. Let me know if that helps?


      • Steve

        video discusses the connection between neurotoxin BMAA and ALS and Altzheimers,
        due to its spread by algae.

        Does this translate into a concern about sea vegetables in the diet?

        • Joseph Gonzales R.D.

          Good question. From what I am learning, it seems different kingdoms of algae produce different toxins. Perhaps the best thing to do is contact the companies that produce the seaweed and ask if they test for BMAA? A quick search and I did not find any information on edible seaweeds, like Nori (Porphyra dentata, a red edible seaweed) and BMAA. Nothing on wakame either. Someone tell me if I am wrong, or if they have searched the literature on this. Thanks , Joseph

    • MGC

      I come from a tropical island. The major source of protein there is sea food by far. Meat consumption was very low because meat was expensive and also for religious reasons. I’d never even heard of ALS until moving to the US.

  • David

    Lou Gehrig was known to eat large amounts of eels which he caught himself. He would go fishing a few times per week and his mother would cook them for him. Here is a newspaper article from 1927 talking about it:

    • Brynda

      I’ve always thought the heavy herbicide use on baseball fields would be connected to ALS. Maybe our ability to detox due to lack of methylating agents could play a part.

    • trent

      Thanks for link and archive with the past. Stunning article. Really poignant is Lou’s mom comment stating Lou would not have achieved his physical prowess eating spinach instead of eels.

      • Fruitopia

        Lou’s mum: expert on everything. Everything vegans say is now irrelevant. Science be damned!

        … If you don’t agree with this website, then why are you here? Necrotarians trolls are disgraceful. You have almost the entirety of western society, can vegans please have some peace in our own space?

        • HereHere

          I didn’t see that comment as a trolling one. He was just pointing out the motherly ‘advice’. Keep calm, and carry on!

        • 2tsaybow

          I do not think that trent is saying anything negative about this site, or about being a vegan. He is simply repeating what was said in an article written in 1927.

          It is nice that you want to help this website by keeping out unnecessary trolling, but it is not the case that trent is trolling here.

          Maybe peace can be found by being nice in our interactions, by giving everyone the benefit of doubt, and by seeing good in others, rather than “trolling”. I think meditation, exercise, and green tea can help as well, Fruitopia.

          You got your space, the internet is filled with “tubes” (That is a joke.) where you can rest, eat some sprouted lentils, and see goodness.

        • MarthaLA

          Perhaps you do not know what poignant means? Trent was not posing Lou Gehrig’s mother as an expert on anything. And she was speaking from what she understood, as did many of our mothers, to be a healthy diet (meat of some kind required). You might try for a little understanding of where people are coming from. Not all mothers were as enlightened as you apparently are.

    • Darryl

      Great find. Eel seems to bioaccumulate BMAA by an order of magnitude more than other species.

      Lage S et al 2015. Biotransfer of β-N-Methylamino-l-alanine (BMAA) in a Eutrophicated Freshwater Lake

      • psisai

        I hope they find out if that is the reason for all als cases. And if it is the reason, can it be reversed by clearing out the body of the toxin? Can tests be done to find out what one’s current level is in their body so they know what steps need to be taken to not get the disease? Save me science!

        • Darryl

          Unfortunately, BMAA appears to substitute for the normal amino acid serine during protein synthesis, and the proteins subsequently misfold, can’t perform their normal functions, and aggregate. There are some experimental treatments for neurodegenerative diseases that increase autophagy, may help clear misfolded proteins and slow progression to clinical outcomes, but the whole problem with protein aggregates is as they mostly appear after our peak reproductive years, our bodies never had the chance to evolve effective means to clear them.

          • psisai

            I guess its good and bad news then. We know how to prevent it, but not cure it.

    • Fruitopia

      So? He wouldn’t have known anything about fish and its dangers in 1927. It’s not what he was studying.

  • albert

    BMAA + Mercury seems like a cocktail I’d prefer to obstain from. This was an extremely important video, Dr. Greger, thank you! (Especially since I have both AD and PD in my grandparents!) BTW interesting topic – garlic fighting metylmercury toxicity (among thousand of other things of course, including beta amyloid neurotoxicity too).

  • As a way to avoid BMAA in concentrations that are harmful, it seems like a vegan diet will do it. As I understand it, it is the bioaccumulation of BMAA in food sources that causes problems, which does not occur in plants. Still, no sense tempting fate by taking blue-green algae supplements.

  • Jerry

    LOL! I love your revision of the Canadian flag!

    • HereHere

      I was thinking a bunch of us Canadian viewers (especially, though other readers too) would be laughing at that one! For sure, I laughed out loud.

  • If BMAA is produced by blue/green algae, is it known whether BMAA is produced by golden algae as well. Recall that golden algae is now being used as a bioconcentrator for long chain Omega 3 fatty acids.

    • Joseph Gonzales R.D.

      Hi salbers, Golden algae doesn’t appear to contain BMAA.

  • Dawn D’Haeze
  • Acreech

    So is cyanocobalamin sources of B-12 a potential source of excess BMAA?

    • Joseph Gonzales R.D.

      Good question, Acreech. No, the B-12 supplements do not contain BMAA it is only found in blue-green algae itself to my knowledge.

    • Alex

      Aside from trace cyanide, cyanocobalamin is the result of a clean synthetic process, produced from fermentation of Propionibacterium which contains no known toxins more or less in a test-tube.

  • UCBAlum

    “I ask about blue-green algae supplements. “Our official policy is that we do not test them,” she says, choosing her words carefully. She refers me to a 2008 paper by Dan Dietrich from the International Symposium on Cyanobacterial Harmful Algal Blooms; he found large quantities of BMAA in commercially sold supplements, including ones containing spirulina andAphanizomenon flos–aquae.”

    • elsie blanche

      Not sure if I’ve asked this before, but how about BMAA content in dried seaweeds like nori and kelp? Seems to me like it’d be a possibility.

  • This is very interesting – Duke ALS clinic may look at Lunasin (epigenetic food) to help combat this disease – hope they find an answer soon.

  • Sherrie

    What about vegan Omega 3 capsules made from algae? Do those contain BMAA? Should we then avoid any and all algae products?

    • Joseph Gonzales R.D.

      Hi Sherrie, Golden algae doesn’t appear to contain BMAA.

  • Robert Haile

    As I stopped eating pork, beef, chicken, etc. I increased my consumption of fish and other seafood. Over many years I developed numbness in my legs with clear progressive spinal stenosis benefited by surgery. When I last saw my neurosurgeon, he sent me to a neurologist for stocking/glove sensory loss. Heavy metal screening showed mercury toxicity after an EMG demonstrated polyneuropathy. After stopping all seafood consumption, not just my sensory problems but a host of vague symptomatology, including insomnia, fatigue, muscle weakness, etc. that I was attributing to aging(66), began to resolve. As an MD who prided himself on nutritional knowledge, I felt quite foolish, but I am now fully convinced that we must consume the very source of energy from our environment and the sun, plants and nothing but plants grown organically without the help of chemical ‘carpetbaggers.’

    • Psych MD

      Today is “Doctors Day.” Not sure if it is a national or local phenomenon. Our hospital is “honoring” the medical staff with a steak and lobster lunch. I respectfully declined, sticking with my daily noon routine of veggie sticks, apple slices and hummus.

      • psisai

        Wow! You go! That is so common in medical settings, whether for patients or others, to have horrible food being served. Food that often is the cause of many of the sick people.

        • jazzfeed

          Good to know the entire medical industry is ignorant (99.9%?), not just myopic docs. Avoid the allopathic conveyor belt, it’s difficult to get off and most don’t.

      • Joe Caner

        Cool, let’s call it the Lipitor/Metformin Lunch-In. We can tell all about our drugs while feeding you a diet that will ensure that you too will be future users of our products.

        • Psych MD

          Actually I take Metformin for its “multitudinous” benefits as far as anti-cancer and anti-aging. 13,332 Pub Med papers and counting.

    • elsie blanche

      Robert, this is very revealing. Do you eat any seaweed? If so, which kind of seaweed? My concern is that seaweed
      might contain some of the toxins and or heavy metals that present themselves in fish and shellfish. Makes a bit of sense.

    • Joe Caner

      “Chemical carpetbaggers,” isn’t that the informal nomenclature for those employed in the sales and distribution of Monsanto’s products?

  • Darryl

    Related videos on BMAA that should probably be linked in the Doctor’s Note:

    Is blue-green algae good for you? August 18th 2010
    Ciguatera poisoning & chronic fatigue syndrome December 31st 2014

    There may be a particular concern with farmed seafood.

    Holtcamp 2012. The emerging science of BMAA – do cyanobacteria contribute to neurodegenerative disease

    Species low on the food chain, including pink shrimp and blue crab—both of which are eaten by humans—had high BMAA levels, comparable to the bat skins from Guam (one crab had 6,976 μg/g). Brand wants to test farm-raised shrimp since, he says, they grow in ponds flush with cyanobacteria.

    BMAA is common at grocers:

    Jiang L et al 2014. Quantification of neurotoxin BMAA (β-N-methylamino-L-alanine) in seafood from Swedish markets

    BMAA was quantified as 0.01–0.90 μg/g wet weight of tissues in blue mussel, oyster, shrimp, plaice, char and herring, but was undetectable (<0.01 μg/g) in other samples (salmon, cod, perch and crayfish).

  • jerryatyoursevice

    Interesting detective story. But, since this mostly relies on epidemiologic data, here’s a outlier:
    who eats more fish than the Japanese? Yet a Nov, 2014 study showed a generally LOW incidence of ALS, especially compared to Europeans and Americans “This is the first report on the annual prevalence and incidence of ALS in the representative population of Japan. We identified some prefectures with a high incidence of ALS. However, the incidence of ALS in the Japanese population was much lower than in the Caucasian populations of Europe and North America.”

    But perhaps a favorable subset to the ALS/Algae Hypothesis may be higher incedense in coastal (greatist fish-eating?) populations:
    “Some prefectures had significantly high SIRs: Okinawa, Nara and Wakayama in the Kii Peninsula, and Niigata for males; Kumamoto for females.”

    • vegank

      very interesting point jerryatyourservice, those are mostly the coastal regions too. I’m wondering if they eat more of a certain type of seafood eg the preserved pink shrimps which is supposed to be a “delicacy” because of it’s sweetness. It also made me wonder again if it is possible for some nations to have a higher level of resistance to ALS, since beef was outlawed in Japan until around 1860’s so people ate mostly vegetables , rice, millet , Tofu and seafood if they could afford it for thousands of years. Mind you seafood was a luxury too so people mainly ate plant based unless they lived by the coast. We also have to remember that since the 1900s and particularly WWII the Japanese began to consume beef and dairy. When we see a video like this it’s rewarding in a sense that we are sticking to plant based whole food even if we go through a few learning curbs. I was concerned about taking algea based omega – 3 but hopefully being the golden algea it would do no harm, since I already have a memory problem without ALS !

    • fencepost

      My experience with Japan and the Japanese I’ve interacted with is that they eat much smaller portions of seafood than we do, and the mix of what kinds of shellfish they eat is much different also.

    • Charzie

      I know it isn’t in the same category but I wonder if it could possibly be a similar adaptation?

  • Matthew Smith

    Eating too much fish, ecosystem magnifiers, can lead to ALS. This site advocates for eloquently staying at eating the primary producers.

  • I guess so, but this is just an association between a modified amino acid and a disease. My friend, who has now passed, did not eat significant amounts of seafood. so if it was BMAA at cause where was it coming from over the 5 years he was eating or (injecting through a fistula) enterics? Has anyone stopped or reversed the disease by ensuring a BMAA-free diet…until now??? has anyone ever stopped ALS?

    • jrs1231

      There are very rare but credible documented cases of ALS remitting and even resolving, but no one understands why. The human mind abhors a vacuum, so when this happens people look around for a simple explanation. Must have been that rabbit’s foot Joe carried around! Richard Bedlack at Duke is now running a program to look more deeply into these cases. Search the web for “ALS Reversals Program”.

      • Thanks, I’ll follow up.

        Having lost my best friend and business partner this way, I will do whatever I can to fight this horror. It marks everyone. His wife, the nurse, the children. None of us can let him go. No one should go that way. I can’t stop trying to think up ways to help someone breath. He suffered so, but fought it with his sense of humor. I’ve never witness such …valor.

        I tried to get him to try the Roy Swank diet, but his digestion was so messed up it was un thinkable to try.

        It seems so impossible now, but I know good science will win in the end.

    • Arjan den Hollander.

      I’ve been inspired into a name change too Gregor :)
      Full circle actually too my first internet pseudonym Holden you know, immature and full of angst ^^, and being a parts collection of my actual name off course.
      Have been collecting personal points of interest on google+ and it just seemed a fitting thing to do, I just had to share that little tidbit with you.
      I tried to find you on google+ but only found two unlikely profiles, you active on + ?

      • ‘‘… and you, Marcus, you have given me many things; now I shall give you this good
        advice. Be many people. Give up the game of being always Marcus Cocoza. You
        have worried too much about Marcus Cocoza, so that you have been really his slave
        and prisoner. You have not done anything without first considering how it would affect
        Marcus Cocoza’s happiness and prestige. You were always much afraid that Marcus
        might do a stupid thing, or be bored. What would it really have mattered? All over the
        world people are doing stupid things … I should like you to be easy, your little heart to
        be light again. You must from now, be more than one, many people, as many as you
        can think of …’’
        – Karen Blixen,
        The Dreamers from Seven Gothic Tales (1934)


        • Arjan den Hollander.


  • jrs1231

    The BMAA line of inquiry is interesting and should be continued, but it’s not the whole story on ALS. There are very likely a number of environmental triggers, including common herbicides and pesticides, according to several epidemiological studies. Too much strenuous exercise may be another trigger. Most ALS researchers believe that the disease involves genetic predisposition plus environmental triggers. A growing number of gene mutations, many of them involved in RNA processes, have been identified as causes of ALS. A recent study in the UK concluded that it takes six steps/events to create a case of ALS – we just don’t know what the steps are.

    I suspect we will soon see genetic screening as standard procedure during the ALS diagnostic workup. Treatments under development for one variety of ALS might not work for others.

    As for the questions about spirulina, the ALS specialists that run the ALS Untangled website wrote a report that can be found on their website. Here is a quote:

    “Some types of blue-green algae contain toxins (10); these include microcystins that are toxic to the liver, heavy metals, neurotoxic alkaloids, and the chemical BMAA, which may even be an environmental trigger for ALS (11). Vendors of Spirulina state that their product is free of most or all of these toxins, but assurance of this supplement is up to the manufacturer or vendor, unlike FDA regulated pharmaceuticals. Even if it is toxin free, there are other real and theoretical and safety concerns related to the use of Spirulina in patients with ALS. One website reports possible adverse reactions to Spirulina including upset stomach, diarrhea, and rash and that there is a potential for more serious allergic reactions (12). Spirulina contains pro-vitamin A, and too much vitamin A can be toxic. Worse lipid profiles may be associated with slower ALS progression (13); thus, the purported lipid-lowering effect of Spirulina could theoretically accelerate ALS progression. Similarly, decreasing macrophage phagocytic activity may slow ALS progression and is now being pursued in treatment trials (14); by activating macrophage phagocytic activity Spirulina could theoretically accelerate ALS progression. ”

    10. Dietrich DR, Fischer A, Michel C, Hoeger SJ. Toxin mixture in cyanobacterial blooms: a critical comparison of reality with current procedures employed in human health risk assessment. Adv Exp Med Biol. 2008;619:885 – 912.


    So what % of vegans have ALS?

  • My late husband died of ALS, and he loved fish. He ate a lot of it, especially tuna, salmon, and catfish.

  • Charzie

    One of the big appeals to me of the plant based diet is the simplicity of it, eating food from the earth as it comes from nature with minimal fuss. So besides the critical supplements, I could never see the point of complicating the issue and wasting money on questionable unregulated supplements and vitamins that can’t measure up to what nature can provide by eating a balanced diet. (Most “average” people seem to use them as insurance for a diet that’s sorely lacking in any real nutrition in the hope that it will rescue them…as if it will!) I get that we all want optimal nutrition, but sometimes wonder if the unknowns of the supplements isn’t almost as scary as some pharmaceuticals…and nearly profitable?

  • Tim Quirynen

    i am taking red algae for the calcium, since a few weeks, maybe i shouldn’t ?

  • Christopher

    So blue-green algae = ALS!?!? #FreakedOut

  • Lana

    What about e3live that’s a blue green algae,touted to be good for you I use that :(

    • Joseph Gonzales R.D.

      I’m not sure about specific brands. Hopefully we can raise enough money through our NutritionFacts Research Fund and test if there is BMAA in certain brands of blue-green algae if that is something site users are asking for. See my comment above for more information on BMAA. Thanks, Lana.

  • What about Chlorella? Does it typically contain notable levels of BMAA?

  • MickG

    I was going to start taking a couple of spirulina tabs daily but after reading this, I’ve decided not. However I probably can’t overcome my addiction to seafood. Oysters, Sardine, Salmon and Shrimp, yum yum!

  • Marlon

    in regards to stuff building up in the brain. what is the significance of the pineal gland becoming calcified? It sounds like something you don’t want to happen. what is the significance of it? apparently fluoride is the cause. fyi , I’m not anti-fluoride. I do think it strengthens teeth. I’m not sure how beneficial it would really be to consume reverse osmosis water or something. so idk..

    • Joseph Gonzales R.D.

      Interesting thought. Definitely something you do not want to happen! I didn’t find anything on BMAA and pineal gland calcification, although many studies are available looking at pineal gland and calcification on diseases that effect the brain like stroke and intracerebral hemorrhage, but I am not seeing any link to fluoride. Share more studies if you find any! Thanks, Marlon.

  • Lawrence

    A small error spoken at about 30secs. Dr Greger says about 3,000 while the screen is showing 30,000.

    • Joseph Gonzales R.D.

      Thanks Lawrence. He does say 30,000 I made sure. Think he just slurred it a bit ;-)

  • James

    so vegan DHA from algae is out or in ?

    • Joseph Gonzales R.D.

      Hi James. Not sure, it a different kind of algae altogether. I wrote more here
      see if this helps?


      • elsie blanche

        Confused. What about Nori seaweed? Is this an algae that might contain the BMAA? Should we
        be concerned about ingesting seaweeds intended for human consumption such as Nori? Thank you,

  • Deitra Jones

    According to Could It Be B12? : An Epidemic of Misdiagnoses by Sally M. Pacholok and Jeffrey J. Stuart, Japan has the lowest rates of brain diseases and the highest rates of B12. NIH says Japan has one of the lowest rates of ALS, yet some areas were high. Are these the areas where the most fish are consumed? The Japanese consume way more fish than U.S. So, is their high B12 negating the BMAA? What do you think is going on here?

    • Joseph Gonzales R.D.

      Does that study address ALS and B12? I didn’t see any mention in the article. Thanks for sharing the book reference I am sure that is what you are referring to when you mention the B12 ALS connection but I have not read the book or know what studies the author references. Link some of them if you get time! Thanks, Deitra Jones.

  • Diana

    My former partner has ALS and does not eat fish nor does he take any type of blue green algae products. Just sayin’.

  • GodBlessAmerica

    Fabulous to know! Thanks Dr. G You’re awesome

  • Darryl

    There’s perhaps a curiously related story. Dr. Oliver Sacks, who hypothesized the connection of BMAA to ALS-PDC, first came to fame for describing his treatment of post-encephalitic patients with the then new drug L-DOPA. In a similar fashion to BMAA, L-DOPA can be mistaken for tyrosine and incorporated into human brain proteins (1, 2, 3, 4). Some foods, notably velvet and broad (fava) beans, have pharmacologically active doses of L-DOPA, enough to improve symptoms in Parkonson’s patients and cause withdrawal symptoms when discontinued (5, 6,7, 8, 9). While there’s plenty of longer term adverse effects with L-DOPA, there’s no evidence to date that either L-DOPA or fava beans contribute to chronic neurodenerative disease (a genetic syndrome favism occurs with fava consumption in a few). But the whole proteomimetic amino acid story is a fascinating one, and this space may be worth watching.

    • And what about your beets? Are you eating them? Why or why not?

      • Darryl

        I was scarred by childhood exposure to beets was canned beets in cassaroles, and haven’t reintroduced them to my diet yet. I get plenty of betaine from the other good source, spinach.

        I hesitated

    • elsie blanche

      Darryl, a couple questions here for you. You mentioned in an earlier post that the ideal diet for the amino acid profile proper balance issue might include a bunch of potatoes a day. Why not just eat a bunch of bananas instead of the potatoes, no need to cook. Is it a sugar/fructose issue? Nannas have good amount of calories and B vitamins as well.

      Also, I am wondering how you feel about the possible detrimental and causative factor that cooked proteins might play in manifestation of brain disorders. I have read over these pages, studies that I am posting here, and some of them make a bit of sense to me but not sure how valid this really is. But it does seem relevant enough to look into. I do not agree with the “diet” regimen that is being suggested by this source, but his/her points seem to carry logic. Hmmmm….wondering if you have any thoughts. Thanks.

  • Dina

    I have been eating Eden brand beans, as recommended on this site, for their iodine from seaweed. Is BMAA high in seaweed?

    • Joseph Gonzales R.D.

      Hi Dina. I am not sure I did not find anything in the literature about kombu and BMAA. I did write a post on this a while back. See if this link helps?

      • Dr Greger/Joseph: Based on this study,… sufficient amounts of serine help to block bmaa from being incorporated into the amino acid chains. I am not sure if having serine is sufficient or if the RATIO to all proteins is more relevant. I reviewed several foods, grains, beans and nuts had higher percentages of serine like 5% to 6%, animal proteins, 3% to 4% and finally fruits and vegetables 3% to 4%. Obviously, you normally get less protein from fruits and vegetables. However if you are a fruitarian and you get a large portion of your protein from fruits and vegetables, you may want to supplement with serine. The animal proteins, being lower in % serine to total proteins may explain why parkinsons is more prevalent in people who consume animal products. (Note animal products do contain higher percentages of glycine that can be converted to serine if there is a presence of sufficient amounts of vitamins B3 and B6 and folic acid along with the required enzymes and coenzymes.

        • Joseph Gonzales R.D.

          Thanks for sharing. Can you repost that study I cannot seem to access it. Serine is not an essential amino acids, so I am not sure how necessary it is to supplement because the body makes enough.

          • Serine may not be essential, but if it is deficient and bmaa is present then it can be introduced in to amino acid chain. if you still have trouble seeing the study I will get you more info

          • Joseph Gonzales R.D.

            Looks like a complex review! Thanks. It seems they are just proposing a hypothesis based on cell and animal studies. At any rate, it’s important to have a well-rounded diet and take steps to avoid BMAA. Eating enough protein (which isn’t a problem here in the States) provided all the serine one needs.

          • The Non-Protein Amino Acid BMAA Is Misincorporated into Human Proteins in Place of l-Serine Causing Protein Misfolding and Aggregation
            Rachael Anne Dunlop,1 Paul Alan Cox,2 Sandra Anne Banack,2 and Kenneth John Rodgers1,*
            Gilles J. Guillemin, Editor

  • Joel

    Would buying ‘farmed’ mussels avert any risk?

  • Rodrigo Cardoso

    Great insight into this subject! Motivated me to translate and spread it. Subtitled in portuguese here:

  • tom

    how about vegan DHA suppliments

  • gardenchild

    Regarding the blue green algae danger, there are several popular kelp products used for japanese cooking, like kombu and Nori. Are these in the blue green algae family? Could they also carry the toxin?

  • Dr Greger/Joseph: Based on this study, sufficient amounts of serine help to block bmaa from being incorporated into the amino acid chains. I am not sure if having serine is sufficient or if the RATIO to all proteins is more relevant. I reviewed several foods, grains, beans and nuts had higher percentages of serine like 5% to 6%, animal proteins, 3% to 4% and finally fruits and vegetables 3% to 4%. Obviously, you normally get less protein from fruits and vegetables. However if you are a fruitarian and you get a large portion of your protein from fruits and vegetables, you may want to supplement with serine. The animal proteins, being lower in % serine to total proteins may explain why parkinsons is more prevalent in people who consume animal products.

  • Mike Grudzien

    Dr. Greger, why is there a cover picture of shrimp and spaghetti on:
    How Not To Die (Plant Based) Diet Cookbook:: Recipes to Help Give You a Prolonged Healthy Lifestyle Free From Disease. Paperback – Large Print, December 12, 2015, by Steve Collins (Author)
    Shrimp are not plants and spaghetti is processed. I don’t get it?

  • Jane

    They say Lyme disease causes ALS,Parkinson’s, and MS…..and Alzheimers !

  • Lou Gehrigs favorite food was eels he caught in Echo Bay New Rochelle, They were highly contaminated with PCBs. PCBs are notorious for causing ALS (see Agent Orange). The oceans are full with plastic, as plastic decomposes it absorbs PCBs. It was recently discovered that phytoplankton is ingesting marine micro-plastic. But there may be an even more devastating effect. Phytoplankton supplies over half the worlds oxygen, and both plankton and oxygen levels are in decline. I have studied this issue for twenty years and my findings are published in my book, The Evolution of Pollution.

    • mich run

      Do you think that eating seaweed, even those listed as “organic”, might now be a bad ideal? I do not see how these seaweeds would not somehow be adversely affected by the plastic in the ocean, and thus absorbing PCBs. Thank you for any thoughts.

      • I’m sorry to say yes. Even fish raised in captivity have PCBs due to the fact they are generally fed fish meal from the oceans. By the way beef and other sources of meat are generally fed fish meal containing PCBs. PCbs are in every living thing on planet earth because they do not degrade but bio accumulate. Even breast milk is bad, a mother dumps up to 80% of her body burden into her new born baby because PCBs have an affinity for fat.

        • mich run

          I am referring to “seaweed”, not farmed raised fish as far as PCBs. My thinking is that seaweed has become toxic as well. Who knows what sort of junk it too is accumulating in the ocean’s sewer. Maybe not PCBs but what about plastic residue, chemicals, etc. that we are not even testing for in seaweed? So, just trying to figure out if seaweed is safe to eat or not, at this point in time (nori, kelp, dulce, et.)

          • All I would do absent any real tests is to assume it is simply because PCBs are found in land vegetation. Its found in marine micro plastic so it is entirely possible. It volatilizes and falls back to earth in rain another possibility that is how it gets into land plants. One must limit things that would likely contain higher concentrations but we must eat. Avoid fat, all fish, and dairy and meat. the government published a 5 volume book describing how toxic PCBs in meat is but it may not be photo copied because it would harm the meat industry. I have all five volumes, its not good. Be safe.

          • mich run

            Thank you. Do you have big concern with plant-based fats such as coconut, palm, large intake nuts and seeds, avocados, olive oil and such as far as PCBs, other toxins in fat? Do you limit plant-based fats for this reason?

          • Not much because they bio accumulate. As fish eat other fish they assume all the body burden of all the previous fish. Not so in plants. As I said we must eat.

          • mich run

            This is an interesting topic, indeed, but one of the things that keeps me curious is the steady, consistent consumption of certain fish/shellfish by lots of Japanese and other asian locals, as well as fish consumption by some of the longest lived populations. Yeah, it makes me wonder how bad occasional, weekly one or two servings of fish really is. I do not think this has been settled, but would like to know your thoughts.

          • The predatory fish bio-accumulate more and as you know the top predator Shark is immune to cancer. Eels are a good indicator because they spend most of their lives in one area. The area itself may be relatively free of toxins depending on what flows into it off the land.

  • Shlomit & Kim

    Question about ALS figures in the US. The video states a 1 to 400 chance of getting ALS. The numbers don’t add us with a prevalence of ALS in the USA at 30,000 among a population of over 300 million people. Also, the percentage of people that get ALS as I understand it is about 1 in 10,000. I’d be grateful for an explanation of the numbers.

  • Jefferson

    I am curious about the contamination one would receive from eating cattle and other animals which are watered at troughs and water-holes filled with floating algae. I work in a number of cattle areas where I see these as the sole sources of water for meat and dairy cows. Is there information regarding cattle as a vector for this type of toxic contamination and resulting medical conditions?

  • Belinda Turner

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    My Husband died of same disease some 3 years back, I become depressed with my own conditions, all I could think was that I have come to the end of my road in life until I got in contact with Dr Osojo through the help of my daughter who searched for an ALS remedy online.
    He and my daughter talked for a couple of day, he also talked with me twice, I got the herbal medicine which he really sent to me. I used for just 3 weeks and, believe me I became better than ever. Am really happy now that I have been confirmed cured some weeks ago by the doctors here in Texas. Thanks to God and you Dr Osojo for your help. I love you.
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  • Kayla

    Does this mean we should avoid algal oil omega supplements?