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Probiotics for Weight Loss

Problems with the good bacteria in the intestines have been correlated with everything from obesity to cardiovascular disease. However, correlation does not mean causation, and certainly does not mean we have successful treatments. So what about microbiota and weight gain? Can we manipulate the microbiota with probiotics or prebiotics to achieve weight loss? The answers might surprise you.

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Dr. Michael Ruscio, DC: Hi, this is Dr. Ruscio, and I want to take a minute to talk about a recent study that looked at the efficacy of probiotics as a treatment for obesity, and then maybe go on a little bit of a rant regarding the microbiota and its implications for potentially being a therapy for weight loss.

DrMR: The paper I wanted to cover briefly here is titled “The Development of Probiotic Treatment in Obesity: a Review“. So, it’s a review paper from 2014 looking at the potential therapy of probiotics for weight loss. If you look in the study you’ll see some exciting and encouraging language being used by researchers…things like “this probiotic was successful at inducing weight loss” or “this probiotic yielded reduction in body fat” or what have you. That could make someone excited, reading that. If you go and pull each one of these papers individually, with a review, researchers will analyze the results of multiple studies. So if you go and actually pull those different papers and look at how much weight loss was actually elucidated by using a probiotic, the best weight loss we see was a little bit over 2 pounds. Is that really something that we can justify spending 50-80 dollars for a bottle of probiotic on? It depends. In my opinion, I think it’s quite an expensive investment to gain, at best, 2 pounds of weight loss. I think that’s really important to mention. Maybe something, along the same lines that’s also important to mention, we could say this: We have strong evidence of a weak effect. We have strong evidence, in the sense that we have randomized clinical trials, the scientific gold standard, of a weak effect. Maybe 2 pounds in some of the best trials. I don’t really think that probiotics are something that can be used to really garner much in the way of weight loss. I think they can work great for a lot of different conditions, but I don’t think weight loss is one of them.

Microbiota in Weight Loss

This also ties into another topic, which is the topic of the microbiota in weight loss. This is something I have to admit I have a bit of a pet peeve regarding, because I see labs and I see other clinicians, or health experts, touting the ability to treat the microbiota in order to achieve weight loss. I really think those claims are either misguided or really, really inflated. Maybe one of the best supports for my position on that would be something known as firmicutes bacteroidetes ratio.

Early animal data showed that if you had this imbalance in your healthy gut flora or bacteria, that imbalance was correlated with weight gain. This created a lot of excitement, and some labs even started reporting this ratio on their analyses. Later, human studies were done, and that relationship was not found to be valid in humans. Unfortunately, that update didn’t really seem to get out in some of the lab and supplement company communities. If you watch my presentation from the Ancestral Health Symposium in 2014 (and I’ll link to that), I did an exhaustive review of the human data looking at the firmicutes bacteroidetes ratio and obesity and weight gain, and there’s really no solid association. We can’t really look at the microbiota in that context and say it’s something we can look at as a treatment for obesity. Not only that, but as I follow the work being continuously published on the microbiota, I’m looking for something that may be an exciting treatment for weight loss.

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Every time I see a certain bacteria associated with being able to help induce weight loss or “high levels lead to weight loss” or “low levels lead to weight loss”, or “we can manipulate this certain bacteria in such a way as to allow weight loss”, I cross check that to see if there are any other studies that reinforce or contradict that. Every time, I have found, if there’s one study showing a benefit, there’s another study showing that there’s no benefit. Meaning: we really don’t have any solid data showing that we can manipulate the microbiota to induce weight loss. Now, that is not going to sit well with some people, I get that, but I think that if you really have an honest look at the literature, you will see that we really do not know nearly enough about the microbiota, and I doubt we’ll ever really be able to manipulate the microbiota to induce weight loss.

I’ll link to that video at AHS here, and I’ll do further videos in the future that go into that in a little bit more detail, but to zoom way out and see the big picture, we have good data looking at probiotics and their ability to garner weight loss. We have nothing to go on there…two pounds. The microbiota and weight loss: exciting data’s being published, interesting associations are being uncovered, but is it something that you should spend money on in terms of testing your microbiota in attempts to find an imbalance that you can treat to allow to you get to some sort of weight loss or body composition gain? I would say absolutely not. If anyone says that, I would really challenge the data they’re using to support that, because I think that is a little bit misguided. Again, I understand and appreciate trying to look through that data and come up with solutions for people, but I take issue with that when there’s not great evidence to support that, and these things can be costly and waste people’s money. I’m all about experimenting if can be done in a cost-effective manner. As soon as you start wasting money, then I think we should be a little bit more conservative.

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Anyway, that’s this video, sorry for being a little bit soapbox-ish there, but hopefully that will help some of you who are trying to figure out what you can do with your gut, your microbiota, and how that relates to body composition and/or weight gain and obesity.

This is Dr. Ruscio, hope this helps! Thanks.

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