Doctor's Note

There is, however, a caveat to the use of chlorella. See my last chlorella video Treating Hepatitis C with Chlorella to make up your own mind if the benefits outweigh the risks.

Here’s the nutritional yeast study I mentioned: Preserving Immune Function in Athletes With Nutritional Yeast.

Here’s some other ways to decrease your risk of upper respiratory tract infections:

The cuddliest way to protect your immune function, though, may be found in this video: Are Cats or Dogs More Protective For Children’s Health?

What else can exercise do? See videos like Longer Life Within Walking Distance and Exercise vs. Drugs for Depression.

More on how to reap the wondrous benefits of exercise in:

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  • Noe Marcial

    seems That for a normal person if train as a maximum of vo2max until 86 %(very intense exercise )… the IgA levels only drop for 1 hour and then came back so that may be mean that one (normal person) it is particular vulnerable during the hour after gym and then the body came back to a balance state. as it was before :) even after 10 weeks of running training(not as an athlete..) . so seems that athletes have to stress much more to drop their antibodies levels :)
    http://europepmc.org/abstract/med/1487340

    • Noe Marcial

      I was thinking that may be to stress that athletes defence lower so Cortisol levels very high.. but i came across this study about Lavanda.. (and i remember the video for Lavanda headaches.. Lavanda sims that decrease cortisol leveles.. but at the same time create oxidative stress in the saliva.. i wonder how bad it is that. or it is just something to don’t worry about if we smell lavender for headache.
      http://www.sciencedirect.com/science/article/pii/S0165178106000114

      • agoscasamento

        I thought exactly like you in this one! I am not sure if we can say that extraneous exercise is responsible for lower athletes inmune system. Specially if we focus on the examples given. International competitions have a lot more into them than just training. Other than that, I just find the videos fascinating! Just the fact that they open an educated debate is awesome!!!

    • Noe Marcial

      maybe singing under the shower after sport may increase the Iga levels! that’s good news for shower singers :), (even do the effect was tested in chloral thingers..)
      http://link.springer.com/article/10.1007%2Fs10865-004-0006-9?LI=true

    • Toni Aparici Galindo

      It’s interesting that about the 1hour after the exercice, i always wonder the mecanism in geting a cold when the air dry your sweat, i think may be your toxins are going out while sweating and then you stop to sweat and some organisms take advantage of that to get in, what science say about it?

      • Noe Marcial

        apparently by some studies suggest that when you sweet the salive get lees and that’s may be one of the reasons for less IgA
        the other is that we have the virus slipping already in our body (virus latentes) and as soon as the antibodies go down they go up ..
        but i’m sure there are more rasons and interaction in this maybe what you says or maybe have to do with the stress of running too? i don’t know ..
        Hemodynamic have replied this :
        Very interesting question. So here’s what I found:
        No they do not know the mechanism yet.
        “One of the next steps is to clarify the mechanisms responsible for the chlorella ingestion-induced increase in salivary SIgA secretion.” Salivary Secretory Immunoglobulin a secretion increases after 4-weeks ingestion of chlorella-derived multicomponent supplement in humans: a randomized cross over study.

        And it appears that the reduction in IgA secretion after heavy exercise is because of reduced Salivary secretion which tends to happen because the body is trying to conserve fluids because you are sweating them out: “In addition, the camp-related decease in salivary SIgA secretion and its attenuation due to chlorella intake were due to changes in saliva flow rates.” Chlorella intake attenuates reduced salivary SIgA secretion in kendo training camp participants.

        Furthermore, “A greater transpiration of saliva during kendo practice than during rest may be a reason for the marked decrease in saliva flow rates. However, these are only speculations. Additional studies will be needed to account for the mechanisms responsible for these discrepancies.”

        What they are trying to say above is when you sweat (transpire–this word is somewhat incorrect because plants Transpire people Perspire/sweat) your body water is reduced and your saliva will decrease because 1. You do not need to eat when working out intensely and 2. Saliva is used for early digestion, so your body will conserve the water used to make saliva, to instead make sweat to cool the body.

        Interestingly it appears that Chlorella signals the Autonomic Nervous system [specifically the Parasympathetic Nervous system (Rest and Digest)] to secrete more saliva. “In the present study, the saliva flow rate reductions during the training camps were greater than the decreases in salivary SIgA concentrations. Thus, it is possible that the effects of chlorella intake on salivary SIgA secretion during the training camp may be more closely related to autonomic nerve regulation than to T-cell function.”

        I can see myself now taking the 30 Chlorella tablets daily (that’s what they used in the study) and being on one of my intense mountain bike rides with my friends as my drool flies up and hits them in their faces. They would say, “Gross, why are you drooling so much?” And I would say, “I’m just protecting you guys.”

  • HemoDynamic, MD – NF Volunteer

    Chlorella Deville chlorella Deville if she doesn’t help you nothing else will

    • lilyroza

      Ah, yes, Chlorella Deville, Cruella’s vegan sister.

      • HemoDynamic, MD – NF Volunteer

        Love it! ;-)

  • Noe Marcial

    do we know how it works the
    Chlorella to increase the IgA ?

    • fineartmarcella

      Check out the references then let us know please… :)

    • HemoDynamic, MD – NF Volunteer

      Very interesting question. So here’s what I found:
      No they do not know the mechanism yet.
      “One of the next steps is to clarify the mechanisms responsible for the chlorella ingestion-induced increase in salivary SIgA secretion.” Salivary Secretory Immunoglobulin a secretion increases after 4-weeks ingestion of chlorella-derived multicomponent supplement in humans: a randomized cross over study.

      And it appears that the reduction in IgA secretion after heavy exercise is because of reduced Salivary secretion which tends to happen because the body is trying to conserve fluids because you are sweating them out: “In addition, the camp-related decease in salivary SIgA secretion and its attenuation due to chlorella intake were due to changes in saliva flow rates.” Chlorella intake attenuates reduced salivary SIgA secretion in kendo training camp participants.

      Furthermore, “A greater transpiration of saliva during kendo practice than during rest may be a reason for the marked decrease in saliva flow rates. However, these are only speculations. Additional studies will be needed to account for the mechanisms responsible for these discrepancies.”

      What they are trying to say above is when you sweat (transpire–this word is somewhat incorrect because plants Transpire people Perspire/sweat) your body water is reduced and your saliva will decrease because 1. You do not need to eat when working out intensely and 2. Saliva is used for early digestion, so your body will conserve the water used to make saliva, to instead make sweat to cool the body.

      Interestingly it appears that Chlorella signals the Autonomic Nervous system [specifically the Parasympathetic Nervous system (Rest and Digest)] to secrete more saliva. “In the present study, the saliva flow rate reductions during the training camps were greater than the decreases in salivary SIgA concentrations. Thus, it is possible that the effects of chlorella intake on salivary SIgA secretion during the training camp may be more closely related to autonomic nerve regulation than to T-cell function.”

      I can see myself now taking the 30 Chlorella tablets daily (that’s what they used in the study) and being on one of my intense mountain bike rides with my friends as my drool flies up and hits them in their faces. They would say, “Gross, why are you drooling so much?” And I would say, “I’m just protecting you guys.”

      • HereHere

        I recently picked up a product that contains cracked cell chlorella. I presume this makes it more bioavailable – hopefully more than a marketing gimmick…
        If so, that might explain the research differences in chlorella studies with different results, though one would have to comb through the methodology of every study to confirm or reject my little theory.

  • 5 Grams of glutamine during training, dissolved in hot water and added to drink bottle, seems to prevent infections.

    I’ve read that glutamine is burned up during exercise and as the immune system runs on the stuff if you don’t put it back in then you are going to get ill. I believe there was a study done where they gave a load of marathon finishers a dose of glutamine at the end of the marathon. The ones that got the glutamine had significantly lower URT infections in the following few weeks.

    I’ve been dosing with glutamine during all extended exercise sessions and haven’t had any URT infections since i began doing so.

    Any thoughts on glutamine studies for this effect, Dr Greger?

  • guest

    “latent viral infections”, you mention. Interesting that when I take vitamin D pills my immune system gets suppressed and I get Epstein Barr type symptoms, as well as flu-like symptoms. VIT D suppresses immune system in some people, right? Differences between our innate immune system and the one we are evolving with.

    • Noe Marcial

      i dont think tat vitamin D suppresses Immune system in place it regulate the Immune system in some cases of autoimmune diseases like Sclerosis multiple or Hashimoto’s thyroiditis. but not suppressing it :)

  • John

    Did anyone read something about Parkinson’s being linked with chorella and/or spirulina consumption? I remember an article in the last couple years…

    • guest

      Chlorella could be messing with the immune system, in a bad way in some people.

    • VegCoach

      John is it possible that you are thinking about the video on ALS, Lou Gehrig’s disease and the connection to blue green algae initially found in Guam and then eventually associated with fish off of Miami?

    • fineartmarcella

      I agree with VegCoach. The nonedible blue green algae that was first suggested as a supplement years ago produced a toxin that is NOT ‘a good thing’, caused all sorts of problems including liver damage

      • fineartmarcella

        But the Chlorella used now as a supplement has many of the health benefits, it also is not the bluegreen algae, so it has never had the bad affects of the other bluegreen algae has, I think it was just confusing in the beginning as people thought all of the algaes were good, but, NOT….

      • guest

        Chlorella is not a blue-green algae.

        • fineartmarcella

          Correct, as I said above it is not

    • Joseph Gonzales R.D.

      Yes, I think you are referring to the videos about blue-green algae and BMAA toxins that VegCoach mentioned below.

      From today’s Doctor’s Note: “There is, however, a caveat to the use of chlorella. See my last chlorella video Treating Hepatitis C with Chlorella to make up your own mind if the benefits outweigh the risks.”

      There is also this post: Do algae-based omega-3 supplements contain beta-N-methylamino-L-alanine (BMAA) that has been found in blue-green algae? and everything you’d want to know about spirulina.

  • Shirley Jean Schmidt

    What’s the best source for Chlorella? Powder, tablet, or liquid? Are there brands that are especially high quality that you can recommend?

    • Joseph Gonzales R.D.

      Unfortunately we cannot recommend any particular brand. I simply don’t know of any brand that may be better over another.

    • Rebecca Cody

      I understand it should be broken cell chlorella, because if the cells aren’t broken it cannot be absorbed. Perhaps all the chlorella on the market is broken cell, but I don’t know.

  • Noe Marcial

    Last question! :) How it works IgA for allergies? more IgA it is correlated with more autoimmune response?

    • Noe Marcial

      https://www.google.com/trends/explore#q=vegan%2C%20paleo&cmpt=q&tz=Etc%2FGMT-1
      VEGAN VS PALEO DIET.. whats says google trends about it :)

    • Rhombopterix

      IgA is an antibody. When you have enough in your mucosa the IgA sticks to pathogens and marks them for destruction. If you do not have enough IgA then the bad bugs survive and can cause disease.

      • Noe Marcial

        thank you! my girlfriend have hashimoto’s thyroiditis. and not all antibodies are good for her. but this one you say that in low quantity increase some autoimmune disease , you know some study about this?

        • Rhombopterix

          nope, did not say that. association is not causation. you seem to be heals over head on this. Best wishes for your girl friend.

          There is a wiki page on selective IgA deficiency and consequences (with refs)

          • Noe Marcial

            Very interesting! thank you , because Celiac disease it is also related with Hashimoto´s so it is not prove or causation but may be a relation between the two thank you again! :)

            “Prognosis is excellent, although there is an association with autoimmune disease. Of note, selective IgA deficiency can complicate the diagnosis of one such condition, celiac disease, as the deficiency masks the high levels of certain IgA antibodies usually seen in celiac disease.[15] Selective IgA deficiency occurs in 1 of 39 to 57 patients with celiac disease. This is much higher than the prevalence of selective IgA deficiency in the general population, which is estimated to be approximately 1 in 400 to 18 500, depending on ethnic background. The prevalence of celiac disease in patients with selective IgA deficiency ranges from 10% to 30%, depending on the evaluated population.[16]”

          • Rhombopterix

            Just a thought Noe, if a person has a disease (Celica, cancer, autoimmune or anything) then they are at war. The battles tend to make the person weaker and their defences can degrade. IgA is a kind of defence. So in my tiny mind it seems logical that people who are coping with Celiacs would have reduced IgA. Further, low IgA in general may be an indication of a previously unknown problem.

  • Plant-Based Cyclist

    My question to Dr. Greger would be: Does eating Chlorella pose any risks similar to those associated with Spirulina?

    • Thea

      Plant-based Cyclist: It does not appear to. Dr. Greger addresses this question in this video:
      http://nutritionfacts.org/video/latest-on-blue-green-algae/

      • planto

        This was an interesting blog post, reading more about potential toxins in spirulina: http://nutritionfacts.org/2014/04/29/toxin-contamination-of-spirulina-supplements/ — it seems like it’s otherwise safe and healthy when grown carefully?

        • Thea

          planto: I agree with you in theory, but I have major trust issues. My take is that this sentence from the blog post you linked to is key: “Spirulina is often grown and collected in open lakes and we have no idea what other algae are going to crop up.” When it comes to spirulina, I just don’t trust that it will be “clean”. I don’t see how we can feel confident that is “grown carefully”. Also, spirulina just doesn’t seem like a necessary food. It seems so easy to get the nutrition and enjoyment that we need is many other ways. So, why do people feel so strongly about pushing the spirulina when there it has some potential significant downsides?

          That’s just my 2 cents. I have no problem with people eating spirulina once they understand the practical risks. It’s green and sounds pretty powerful for a food…

          Thanks for including that link. I remember that article and think it is a good one for people to see in this conversation.

          • planto

            >his sentence from the blog post you linked to is key: “Spirulina is often grown and collected in open lakes and we have no idea what other algae are going to crop up.”

            It seems like growing Spirulina in an isolated GMP-certified laboratory environment with regular testing of each batch would provide a decent level of safety. In the comments thread from that blog post, there’s mention of a company “Nutrex” which does just this.

            http://www.nutrex-hawaii.com/blue-green-algae-and-microcystin-toxins

            In the past, I’ve thrown chlorella / spirulina into smoothies for the deep color it provides, viewing it like any other plant — perhaps it’s better removed from the diet.

          • Thea

            planto: More great info.

            re: “perhaps these are better removed from the diet” I think you seem very aware of the risks and potential benefits. So, I don’t see a reason to leave those out of your smoothies if you enjoy them (or enjoy the color) and you feel you can trust the Nutrex or similar company. I agree that if they are following the protocol that they list, it seems like it would be pretty safe…

            One more thought: I checked that FAQ page for Nutrex. They do say that spirulina offers better nutrition, but they don’t post any data to back up that claim. It may be true, but it seems like they would want to back up that statement with some solid studies? If it’s not true, what else might they be fudging on?? (That’s my inner sceptic (or inner paranoid depending on your opinion) coming out.) Note: They may have that info elsewhere on their site. I didn’t check.

    • Joseph Gonzales R.D.

      And to back up Thea. See Doctor’s Note above: “There is, however, a caveat to the use of chlorella. See my last chlorella video Treating Hepatitis C with Chlorella to make up your own mind if the benefits outweigh the risks.”

      • Thea

        Ah, I forgot about that one. Thanks.

  • Noe Marcial

    i couldn’t buy the Kindle version of how not to die :( amazon uk says it not my place and amazon america says error..)

    • Toni Aparici Galindo

      i brought the book version because the kindle version said it wouldn’t be available until february, i’ll get the book by 23 of december, i can’t wait shame on living in Spain

      • Noe Marcial

        que bueno verte por aca :)
        cuanto te salio el envio?

        • Toni Aparici Galindo

          Gratis aproveché lo del premium gratuito por 1 mes

  • Whit22

    What about radiation from the Fukushima disaster? How can we know the source is not from the Pacific? Even then it won’t be long before all the oceans are tainted with it.

    • Rebecca Cody

      Doesn’t Dr Greger say chlorella is a fresh water algae?

  • Panchito

    Last year, a new study came up about a chlorella virus that makes people less smart

    ATCV-1 = Acanthocystis turfacea chlorella virus 1

    http://news.sciencemag.org/biology/2014/10/algal-virus-found-humans-slows-brain-activity

    • Kartoffelmao

      Interesting, but i doubt its of any relevance to dried (dead) chlorella. Ive been taking chlorella for 7 years and i still have a mensa level IQ. ;)

  • Rhombopterix

    If youre an athlete who trains so hard that it harms you is it correct to term that as athleticism? Enter flames below:

    • It’s not that an athlete trains so hard that it harms them, it’s that some don’t bother with, or correctly understand, correct nutrition and recovery. If i did my training without bothering to consider what nutrients by body requires and replace them accordingly then i would do more harm than good.

      The other thing to consider with athletics is that it is about pushing the boundaries. As a species we have never done some of things that some people are now doing and our bodies never evolved to do them. Tour de France is a prime example of this. So it’s important to bear in mind if you are an athlete and pushing the boundaries that you need to take nutrition very seriously indeed.

      • Rhombopterix

        Would you like a little Edgar (as in erythropoetin) with that salad? cheap shot i know…I just read “The Secret Race”.

        Aren’t you assuming that the athletes in the studies, the ones with low IgA, were not taking nutrition seriously? The one who are serious have normal immune function? I hang with some serious cyclists. When i pushed the subject they told me that many (sounded more like most) use epo to boost hematocrit. (This is not USA btw/ but I think it is the same amongst athletes around the world). What would you say about that? How much doping goes on?

        • Yes i do say that they aren’t taking nutrition seriously. You just have to see what pro cycling team riders are being fed by their dieticians to realise that they’re not taking it very seriously. Fish, meat and eggs are not healthy foods. And all those gels, pure maltodextrin and fructose and other chemicals and shit that they take while riding isn’t exactly taking nutrition seriously either – it’s making the best of a bad world. The teams don’t give a fuck about the later life health problems of their riders, they’re just out to make as much money as possible winning races right now, tomorrow be damned. And let’s face it, most athletes don’t care about future health problems, they just want to win now and to hell with the future as well.

          I suppose it’s two schools of thought. Those who train to win and will do whatever it takes to win, and those who train to stay fit and healthy. The former do not do nutrition for health and fitness for life, they do it for the momentary gains now, and that’s not taking nutrition seriously in my book, that’s abusing nutrition.

          I have no idea how much doping goes on. I don’t, never have and never will use PED’s. But i do realise that when websites like Strava running KOM and QOM competitions on every sector being heavily fought over by all and sundry the temptation to cheat and take PED’s must be incredibly tempting for those kinds of peoples who only care about beating others whatever the cost to their later health.

          I think the problem is that in amateur athletics there is no ban on doping, so inevitably it will be rife. But i don’t give a toss about winning anything and i’m not competing against anyone but myself so i have no desire or need to cheat.

          Ergo, don’t paint all athletes with the same brush. There are some who are in it purely for the health and fitness benefits, not just to win at any cost.

          • Rhombopterix

            so how are your IgA levels after you push these evolutionary boundaries? Do you wear that collar when you do the pushing? heh who is that?

    • Was that flamey enough? :-D xx

  • TimX

    So how much chlorella should I take to get immunity benefits? 30 tablets per day (as one of the studies in the video did) seems obnoxious to me.

    • Brux

      On seller on Amazon sells them for $0.10 cents per tablet … so 30 would be $3.00 a day. They probably taste nasty too, so maybe have to get the chocolate covered ones … I hope! ;-)

    • Kartoffelmao

      30 x 200mg is only 6grams. You can buy it in powderform also, and just take a tablespoon.

  • Timar

    I initially read this as “Preserving Athlete Immunity with Cholera”…

  • Fred

    The IgA charts seem to correlate highly with blood O2 levels which tend to drop similarly after strenuous exercise and other stressful events? What’s the connection?

  • planto

    Are heavy metals a concern with chlorella? Are there any brands or sources that are particularly clean and healthy?

    • Kartoffelmao

      Yup, clean chlorella from naturalnews is tested for contaminants like that.

  • Stefan Lang

    How much Chlorella should we consume on a daily basis?

    • Thanks for your question Stefan!

      To get similar benefits as the one reported on this study mentioned by Dr Greger, take 30 chlorella tablets per day (15 tablets × twice, after breakfast and dinner). The mass of each tablet described in the study was 200mg.

      Hope this answer helps!

      • Thea

        Thanks Darchite. I was wondering that too. I bought some chorella tablets after seeing this video. But I was sort of taking 5 a day. And I don’t even know if they have 200 mg or not. Obviously I might have to up my intake to see much benefit.

  • Brux

    A lot of innuendo here … OK, what are we supposed to take, and how much of it do we need … and what is the cost of all of this stuff. And how would we know if we are getting good chlorella or bad chlorella … that is what all the supplement makers claim, organic, screened for heavy metals, ours is the special chlorella from the special part of the unpolluted world that if you do not take you will get worse instead of better. Just curious, as usual?

  • Brux

    Wikipedia says that – “Chlorella, too, was found by scientists in the 1960s to be impossible for humans and other animals to digest in its natural state due to the tough cell walls encapsulating the nutrients, which presented further problems for its use in American food production.[3]”

    What does that really mean. Are chlorella pills or edible chlorella processed in some way to be digestible?

  • adam

    Does Spirulina produce the same results?

    • Thanks for your question Adam!

      This short summary explains why Spirulina should be avoided, regardless of its potential benefits.

      Hope this answer helps!

  • Tom Pavant

    How do IgA levels influence reactivation of EBV or any viral reactivation (which occur intracellularly) ?

  • newjumpswing

    Aloha,How many mgs is 30 tablets? Back in the day the tablets were very small about he size of aspirin if not smaller.

    • Thanks for your question!

      In the study mentioned by Dr Greger, each chlorella tablet had a mass of 200mg.

  • Jason

    Is there a brand of Chlorella that is recommended?

    • Kartoffelmao

      I use clean chlorella from naturalnews. Its tested for contaminants like heavy metals and radiation.