Probiotics are all the rage right now, claiming benefits that range from balancing gut bacteria, curing diarrhea and other digestive system issues, improving muscle performance, boosting the immune system, improving cardiovascular health and mental health, decreasing inflammation, and aiding in fat loss. But how many of these claims actually ring true?
When it comes to muscle performance, research does not show any direct effects, positive or negative, from probiotics. There is also no significant evidence (at this time) supporting the benefits for heart health, mental health, or inflammation, although research continues on this topic. We don’t even know for sure how probiotics can aid in various digestive problems.
There are, however, findings to support that probiotic use has some benefits in regards to upper respiratory infections in elite athletes. The graph shows respiratory infection incidence in sedentary individuals, recreationally active individuals, and elite athletes (Helms 2019). These infections are more common in elite athletes, and this is believed to be due to the large amounts of intense exercise increasing the risk of infection by decreasing gut perfusion and increasing gut permeability- something that could possibly be improved by probiotic use.
Overall, although we know the body’s microbiome is important, there is still so much that we don’t know about it. Therefore, there are no specific, evidence-based recommendations for probiotic use/dosage at this time. Remember that probiotic products can vary greatly in included strains, amount of colony-forming units, and results. In general, probiotics have not been shown to be harmful in healthy populations, but it’s definitely good to be wary of hyperbolic claims and marketing.
Takeaways? If you want to take care of your gut health, ensure that you are consuming at least 25 grams of fiber per day and drinking plenty of water. It is likely that if you choose to use probiotics that you will see no benefit or a small benefit. If you are an elite athlete (ex: deep in contest prep) it may be beneficial for you to take a probiotic.
-Katy Hair, RD, LDN, CNSC
Helms, E. Probiotics: Is the Hype Real? Monthly Applications in Strength Sport. 2019 Mar; 3(4):57-64.
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Kerry RG, Patra JK, Gouda S, Park Y, Shin HS, Das G. Benefaction of probiotics for human health: A review. Journal of food and drug analysis. 2018 Jul 1;26(3):927-39.
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