Probiotics, or beneficial bacteria, have been studied for a number of health conditions, but one of the most exciting benefits of probiotics is their effect on the common cold. A number of studies have looked at probiotic treatment and prevention of upper respiratory tract infections (cold and flu, most notably). A recent systematic review evaluated data from twelve randomized, controlled trials in children and adults and found that those people who had taken Lactobacillus and Bifidobacterium probiotics experienced fewer days of illness, shorter illness episodes, and fewer days absent from daycare, school, or work when compared to those participants who took a placebo.

“This paper shows that with the addition of live lactobacilli and bifidobacteria to your diet, the duration of upper respiratory tract infections (e.g. colds) could be shortened,” stated Sarah King, PhD. “Combined with results from a 2011 meta-analysis published in the Cochrane Database of Systematic Reviews, which demonstrated that probiotics can reduce the incidence of upper respiratory tract infections, the implications of these findings are significant and could translate into cost savings and quality of life improvements.” The economic impact of colds is estimated to cost the United States $40 billion each year, so any reduction in the common cold is welcome.

Probiotics impact the immune system in a number of ways. Up to 80 percent of the immune system resides in the gut. The gut bacteria help to educate the immune system so that it responds appropriately. So it’s no wonder that probiotics have a beneficial effect on the respiratory tract.