Probiotics found in yogurt or dietary supplements contain potentially beneficial bacteria or yeasts.

A systematic review of the efficacy of probiotics in IBS included 19 randomized controlled trials that involved 1,628 IBS patients found that probiotics are effective in IBS. However, they found there was not enough information to be sure whether there is one probiotic that is particularly effective or whether combinations of probiotics are required.

Study leader Dr. Paul Moayyedi and colleagues at the Mayo Clinic in Jacksonville, Fla., and Rochester, Minn.; McMaster University in Hamilton, Ontario; University College in Cork, Ireland; and Montefiore Medical Center in New York City, conducted the meta-analysis.

The findings were presented at the American College of Gastroenterology annual scientific meeting in Orlando, Fla.