Probiotics are live microorganisms that, when taken in adequate amounts, confer a health benefit on the host (that’s you). Probiotics are most known for their digestive benefits because the digestive tract is where they work. Not everyone is aware that probiotics also have important immune health benefits, primarily because up to 80 percent of the immune system resides in the digestive tract. The gut-associated lymphoid tissue (GALT for short) is situated in and around the intestines and is in constant contact and communication with the microbes (which includes the probiotics) living in the intestines.

Probiotics play as much a role on immune health as they do on digestive health. A recent study published in the journal Clinical Nutrition highlights the immune benefits of the probiotic Bifidobacterium lactis. The study involved 465 healthy adults average age 35 and found that those participants who took 2 billion CFUs (colony forming units) of Bifidobacterium lactis daily for 150 days had a 27 percent reduction in the risk of upper respiratory tract infections (that’s a fancy way of saying the common cold) than did those participants who took a placebo.

“This study adds important new information regarding the effects of probiotic supplementation for respiratory illness,” wrote the authors. “The positive effects of probiotic supplementation appear to extend beyond individuals considered to have a higher susceptibility to illness.” They also found that the time it took for participants to get sick was delayed by 0.7 months in those people taking the probiotic when compared to those taking placebo.

This study shows that daily supplementation with B. lactis has important immune benefits even for healthy people who want to ward off the common cold.