Taking probiotics has health benefits, but preventing childhood asthma isn’t one of them, according to published research led by medical scientists at the University of Alberta, Canada.

Researchers reviewed data from 20 clinical trials in Europe, Australia, New Zealand, and Taiwan that involved more than 4,800 children whose mothers either took probiotics during pregnancy or gave probiotics to their babies in the first year. The rate of doctor-diagnosed asthma was 11.2 percent among infants who received probiotics and 10.2 percent among babies who received the placebo.

“Taking probiotics had no effect on the asthma rate,” said principal investigator Meghan Azad, a Banting post-doctoral fellow in the Faculty of Medicine & Dentistry at the University of Alberta, who works in the Department of Pediatrics. “We haven’t shown there’s any harm in giving probiotics, but it can’t really be advised as a strategy to prevent asthma.”

That doesn’t mean probiotics aren’t good for other reasons, Azad pointed out. “There’s really good evidence that probiotics are beneficial to infants who are born preterm and suffer from a bowel condition,” she added. “There’s also good evidence that probiotics might prevent eczema.”

Her team made another finding that warrants more research: babies who received probiotics as infants or in utero had higher incidences of lower respiratory infections.

“This study identified a potential association between probiotics and lower respiratory infections,” Azad notes. “But more research is required to see if the two are indeed linked.”