Are Probiotics Safe? We Really Don't Know

Arefa Cassoobhoy, MD, MPH


August 06, 2018

Hello. I'm Dr Arefa Cassoobhoy, a practicing internist, Medscape advisor, and senior medical director for WebMD. Welcome to Medscape Morning Report, our 1-minute news story for primary care.

Have you been asked by patients about taking probiotics? What do you base your answer on? As supplements, rather than drugs, probiotics aren't subjected to the same degree of scrutiny by regulators.

It turns out that very few probiotic or prebiotic studies report any data at all on specific harms. In a recent meta-analysis of nearly 400 randomized trials, only 6% adequately reported safety data. This includes the number of participant withdrawals related to harms, and the number and type of adverse events.

This leaves clinicians in a difficult position. Although research shows promise for probiotics in preventing and treating some gastrointestinal conditions, it's impossible to tell patients that these products are completely safe.

In fact, from what we know so far, the only answer we can give with confidence is that we really don't know.

Follow Dr Cassoobhoy on Twitter: @ArefaMD


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