Probiotics, the healthy bacteria in yogurt and supplements, could do more than help your digestive system -- a new review of studies show they could also help to stave off colds.
Chinese researchers analyzed 10 studies that gave probiotics, a placebo or no treatment for more than a week to a combined total of 3,451 study participants whose ages ranged from infancy to adulthood (40s). They found that taking probiotics could help reduce the number of upper respiratory tract infections by 12 percent.
"This indicates that probiotics may be more beneficial than placebo for preventing acute URTIs," researchers wrote in The Cochrane Library review. "However, the results have some limitations and there were no data for older people."
MedPage Today reported a possible reason why probiotics could help against colds:
Probiotics, which most commonly include lactic acid bacteria and bifidobacteria, may exert their immune-boosting effect by bolstering gut wall integrity and amping up activity of phagocytes, Dong's group explained.
Past studies have shown that probiotics could help relieve the symptoms from irritable bowel syndrome, though more research needs to be done on what kind of how many doses of probiotics are needed for a sustained benefit (since IBS is a chronic condition).
A Cochrane review also shows that probiotics could help to reduce the length of time people suffer from acute infectious diarrhea. But just as in the other study, more research is needed to find the right kind of probiotic to be used as a treatment.
Probiotics have also shown some promise for treating bad breath, reported HuffPost blogger Dr. Harold Katz.
Last year, a Pediatrics study showed that probiotics could also help stave off diarrhea in kids when they are taking antibiotics that can cause diarrhea as a side effect. However, there were many caveats to the study; for one, kids whose immune systems are compromised or who are using intravenous catheters shouldn't use probiotics because they could risk a serious infection, the Associated Press reported.
A recent animal study in the journal Proceedings of the National Academy of Sciences has also shown that probiotics in dairy could aid in treating anxiety and depression, the Daily Mail reported.