Weight Gain after Fecal Microbiota Transplant

FMT, or fecal microbiota transplant therapy, is a procedure where you can recolonize your gut with the microbiota from another person. This therapy can literally be a life-saver for reoccurring clostridium difficile infection. But there are important side effects to be aware of with FMT, like weight gain.

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Weight Gain after Fecal Microbiota Transplant

Dr. Michael Ruscio: Weight gain after fecal microbiota transplant.

Hi. This is Dr. Ruscio, and perhaps you’ve heard of a very interesting new therapy called fecal microbiota transplant therapy. This is essentially where we take the bowel movement of one person, the feces of one person, and transfer that into the intestine of another person to help recolonize the bacteria in the colon. This therapy has turned quite a few heads—and rightfully so—because it is quite a bit different, I guess, you could say, but it does have a somewhat long history of use, going way back to ancient days in China as a therapy that helps with certain gastrointestinal conditions. It’s been receiving more attention lately, especially in the treatment of recurring Clostridium difficile infections, which can be quite problematic. It’s also been recommended for many other gastrointestinal conditions… or I shouldn’t say “recommended,” but people have been wondering how helpful it could be with other gastrointestinal conditions. There is a little bit of evidence for inflammatory bowel disease, that it may be helpful for Crohn’s and also colitis, and there is some experimentation going on with other conditions. The best evidence we have is really for recurrent Clostridium difficile infections.

Recently a case report study (1 Trusted SourcePubMedGo to source) was published showing how a woman gained weight—in fact, she became obese—after receiving a fecal microbiota transplant from a healthy donor. An overweight, but healthy donor actually caused this woman to become obese. Now, this woman had recurring Clostridium difficile infection. She received the fecal microbiota transplant therapy, and that recurring infection went away, which was good, but she also became obese/overweight, likely because of the effects from the transplant that she had.

Of course, when using a donor, we want to try to find the healthiest donor possible. This study is interesting because it highlights how important the donor is and perhaps highlights another reason for being cautious with this therapy unless it’s the only option, because we may find in the future there are other interactions that we’re not aware of until someone has a negative side effect from the therapy.

Certainly I’m supportive of this FMT therapy if there is no other option, but because it’s so new, if there is another option, I would exercise and exhaust all my other options first because God forbid you had some sort of reaction to the particular microbiota transplant that you had. You may end up with some side effects that may be fairly hard to get rid of because there’s a vast world of bacteria within a microbiota and we still don’t completely understand how one bacterial microbiota interfaces with the genes of another person. So, again, until we know more about it, we probably want to be a little bit cautious.

So you can potentially gain weight from a fecal microbiota transplant if you’re not careful with who your donor is.

All right. Hope this helps. Thanks.

If you need help assessing the connection between your gut and your weight, click here.

What do you think? I would like to hear your thoughts or experience with this?


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