Do probiotics help IBS?

What the evidence says

Probiotics are live bacteria or yeasts taken as supplements or in foods, meant to support a healthy gut. Some people with IBS, a common condition causing stomach pain, bloating, and changes in bowel habits, try probiotics to ease their symptoms.

The Canadian Association of Gastroenterology reviewed the evidence and suggests probiotics as an option worth trying for IBS, alongside things like peppermint oil, though it is not a strong recommendation. The UK's British Society of Gastroenterology and the Japanese Society of Gastroenterology give similar suggestions. However, the American College of Gastroenterology in the US actually recommends against using probiotics for overall IBS symptoms, showing how much disagreement there is.

When scientists pool together many studies (called meta-analyses), some find that probiotics can meaningfully reduce pain and bloating compared to a fake pill (placebo). Other reviews find the results are inconsistent, meaning some studies show a benefit and others show none. This is likely because there are many different probiotic strains and combinations, and researchers have not agreed on the best one for IBS.

Because the science does not point to one clear answer, and different expert groups reach different conclusions, this is graded as mixed evidence. That means probiotics might be worth trying since they are generally safe for most people, but nobody can promise they will work, and no specific strain or brand has been proven best for everyone with IBS.

If you are thinking about trying probiotics, it is a good idea to talk to a doctor or pharmacist first, especially about which product and dose might be reasonable to trial, and for how long.