A recent study from Georgia State University found that mice that were pre-treated with a nasal application of a strain of heat-killed lactobacillus (lactic acid) bacteria and then infected with the influenza A virus recovered from the illness with mild symptoms. The mice were also later protected from other types of the flu. By comparison, mice that were not pre-treated suffered more severe symptoms, including significant weight loss.
"The lactic acid bacteria that was used [in the study] was isolated from kimchi, a Korean fermented cabbage,” says study author Sang-Moo Kang, Ph.D., professor in the Institute for Biomedical Sciences at Georgia State University in Atlanta. Although the study was done on mice, Kang speculates that with further research, a nasal spray containing lactic acid bacteria may one day protect against the flu in humans.
Until such a spray becomes available, adding more probiotic-rich foods to your diet, including fermented vegetables, may help you stay healthier this winter and beyond, says Kang. Try incorporating sources such as sauerkraut, kimchi, tempeh, miso, kefir, yogurt and fermented pickles.