Probiotics and Diarrhea

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Probiotics & Diarrhea

Probiotics have slowly moved from the field of alternative medicine into the mainstream, particularly for the prevention of antibiotic-associated diarrhea and the treatment of gastroenteritis.

After taking antibiotics, up to 40 percent of people experience diarrhea. Administering probiotics along with the antibiotics, though, may cut this risk in half. Which kinds and how much? Lactobacillus rhamnosis and Saccharomyces boulardii appeared to be the most effective strains, and studies using more than 5 billion live organisms appeared to achieve better results than those using smaller doses. For example, taking 100 billion organisms seemed to work nearly twice as well as 50 billion in preventing antibiotic-associated diarrhea.

Of course the best way to avoid antibiotic-associated diarrhea is to avoid getting an infection in the first place. See, for example:

We can also try to avoid consuming antibiotics in our diet: Lowering Dietary Antibiotic Intake and More Antibiotics In White Meat or Dark Meat?

The second well-established indication for the use of probiotics is in the treatment of acute infectious diarrhea, shortening the duration of symptoms by about a day. We still don’t know the best probiotic doses and strains. Studies have used between 20 million organisms a day to 3 trillion, and there are thousands of different strains to choose from. Then, even if we wanted a particular strain, odds are the label is lying to us anyway. Less than a third of commercial probiotic products tested actually contained what the label claimed. About half had fewer viable organisms than stated, and half contained contaminant organisms–including potentially pathogenic ones–as well as mold.

The mislabeling of probiotic supplements will come as no surprise to those who’ve been following my work. For example:

Ideally, we’d repopulate our gut with the whole range of natural gut flora, not just one or two hand-picked strains. This has been attempted for serious infections, starting back in 1958. Patients were given a fecal enema. Gut bacteria was taken from a healthy colon and inserted into someone else’s unhealthy colon. Or we can go the other route and administer the donor stool through the nose. Evidently, this route of administration saves time, is cheaper, and less inconvenient for the patient.

Preferred stool donors (in order of preference) were spouses or significant others, family members, and then anyone else they could find (including medical staff). Doctors picked a nice soft specimen, whipped it up in a household blender until smooth, put it through a coffee filter and then just squirted it up the patient’s nose through a tube and into their stomach. Don’t try this at home!

How receptive were the patients to this rather unusual smoothie recipe? None of the patients in this series raised objections to the proposed stool transplantation procedure on the basis that it “lacked aesthetic appeal.”  However, since production of fresh material on demand is not always practical, researchers up in Minnesota recently introduced frozen donor material as another treatment option.  All described in great detail in the latest review on the subject out of Yale entitled, “The Power of Poop.”

Another mention of frozen “poopsicles” can be found in my video Relieving Yourself of Excess Estrogen.

Preventing and Treating Diarrhea with Probiotics is the first of a four-part series on the current state of probiotic science. See also:

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 – 2015 presentations Uprooting the Leading Causes of Death, More than an Apple a Day, From Table to Able, and Food as Medicine.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

21 responses to “Probiotics & Diarrhea

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  1. Aloha Dr. Greger,

    How is it that fecal matter can be taken through the nose and travel into our stomachs without causing us to get sick?


  2. This is just gross! I shake my head at silly SADs, when they say, ‘I could never do that.’ However, I would rather die than eat…..fecal matter.

    1. Even if it could save your life? Gut bacteria can get so out of balance that this could actually save you. Just a thought, tho I agree that it would be “hard to swallow” hahaha.

    2. I share your view, though it is interesting to note that many animal species do not regard this subject the same way and, in fact, regularly practice coprophagia.

      Quoting Wikipedia, “Human perception of the odor is a subjective matter; an animal that eats feces may be attracted to their odor.”

  3. My fish-eating friends say that selenium binds to mercury and therefore if you eat seafood with selenium rich foods then mercury is not an issue. Is this true? I show them your videos and they are not convinced. What does the science suggest?

  4. The human microbiome is plays a crucial role in health and is tightly linked with diet and genetics as a health determinants.

    Building on this article by Dr. Greger is the National Academies Press book on The Human Microbiome, Diet and Health. In particular, starting from page 92 there is an extensive discussion on probiotics and prebiotics.

    This is a must read book for anyone interested in obtaining the latest understanding of how gut microbiota affect health. I learned so much from this book, including such topics as:

    – the connection between the microbiome and obesity as well as nutrient metabolism;
    – the difference between prebiotics and probiotics,
    – why breast milk is safer than infant formula;
    – risks associated with Caesarean sections;
    – how bacteria evolve resistance to antibiotics through horizontal gene transfer;
    – dangers associated with antibiotic use and unsanitary conditions in factory farming.

  5. Interesting how some people claim to be horrified at the thought of eating animal “secretions” (eggs, milk products) , yet would not hesitate to scarf down human…um, sheeeyet.

    1. Kitsy: I know you are trying to be funny, so I don’t know if you were deliberately misunderstanding the post in order to make a joke (in which case you can stop reading here), or if you really missed the content of what the post is saying.

      For you or anyone who might have missed the point of the post: Those people who are getting fecal transplants are not vegans per say, but people with severe gut problems who desperately need help. And as the above post points out, you are far, far more likely to avoid being in such a situation in the first place if you avoid eating those animal secretions and flesh. Thus, you can hopefully avoid having to “scrarf down human…um, sheeeyet” by eating whole plant foods!

      Hope that helps.

      1. Thanks for responding, Thea. I admit my little “joke” was pretty yucky. :-) But as far as recommending a whole plant foods diet, you’re pretty much preaching to the choir here. I don’t eat animal “secretions” either — I just find it hilarious for such foods to be referred to in that way.

        Yup, a healthy diet is very important — it’s too bad so many folks have to learn things hard way.

        1. :-) Ah. Now I see where you were coming from.

          I agree with your last sentiment too. But since I’m one who often takes the hard way on about any topic, I can hardly judge.

  6. I’ve recently joined an IBS forum where people are discussing something called ‘SIBO’ – and FMT is one of the treatments people say can ‘cure’ IBS, particularly those with this proposed condition ‘SIBO’ – which is gaining recognition from various available breath tests. I see there is no mention of this condition on this site but I wondered if Dr Greger or NF people had heard of it?

    My ‘IBS’ became so debilitating recently I was forced to investigate it. I am experimenting with some herbal anti-microbials and experiencing improvements but I think the real problem is my Colon and this article and FMT I find intriguing, yet without any other diagnosis other than ‘IBS’ I feel I won’t be offered FMT here in the UK. Anyone have any information?

    1. Dear Mike, You have had enough tests, you don’t need to waste any more time on ineffective diets. You NEED FMT! The Taymount clinic in the UK provide this service. They also supply the NHS with pre-screened fecal matter. If you can afford it, go to the clinic and get your life back. Option 2, The Taymount clinic also supply pre-screened fecal matter to the general population for self treatment. Option 3 (this is not a joke) Coprophagia.
      Donor fecal matter can be inserted into delayed-release capsules and consumed orally. All three methods of bacterial repopulation are highly successful, side-effect free, and most importantly, they will actually cure you.

  7. I have a hiatial hernia….I am not sure if ghis is causing my ibs symptoms…so fmt could be a waste of money? Anyone have experience with surgery? Is it dangerous?

    1. FMT can be self administered, at home, for very little money. Donor fecal matter is free if you have any healthy friends or non-mentally ill family members. Screening of donor material is also free, send your donor to their GP and ask for an comprehensive health check including a stool sample. The route of administration is key to a lasting cure. IBS responds well to retained fecal enema, however if you’ve got SIBO this will be ineffective. The only way to get to the small intestine is via the mouth. The choice is yours, spend the rest of your life in misery listening to doctors bullshit (they don’t want you to get better, they want to maintain your disease), or take matters into your own hands, cure yourself, start living again.
      P.S. I have studied the work of Dr Mark Pimentel, Alison Siebecker and read well over 200 medical papers on this subject over the last 15 miserable life destroying years. Its not in your head, its got nothing to do with food, your hernia is not the problem, and the NHS is 10 to 20 years behind the curve. This shit actually works, pun intended.

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