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The claim? Probiotics improve your digestive system, boost your immunity, and even ward off the flu. Now a new study launched by a Danish company that makes probiotic products says kids on probiotics had fewer flu symptoms than kids who didn't over the course of one winter.
In that study, only 18 percent of kids taking two kinds of probiotics had a fever over a six-month period, versus 66 percent of the kids taking none. And only one-third of the probiotics group had a cough or runny nose, versus more than 80 percent of the kids taking nothing.
"The majority of our immunity is actually centered in our gut. That's why it's not very surprising to me that we're seeing a role for probiotics in the prevention of flu and upper respiratory infections," said Dr. Tasneem Bhatia, medical director of the Atlanta Center for Holistic and Integrative Medicine.
Some doctors caution the new study, ordered by a company with a financial stake in its success, only tested two specific strains on children in China. Additional studies have also found illness-fighting benefits in probiotics, but other studies have questioned whether they have any value.
Doctors say this flu season, parents should still focus on the basics.
"Namely, getting vaccinated, washing hands, avoiding people that are sick and if you're sick yourself or your child is sick, keeping that child at home," said Dr. William Shaffner, Vanderbilt University.
Infectious disease experts note that since the study was conducted on children in China, researchers really need to do a larger scale study here in the United States.