This study, and other works from Dr. Stappenbeck lab, brings home that in order to fend off infections, we must both be ingesting a plant pigment rich diet with abundant fiber and have a healthy microbiome. The result is that beneficial germs for whom we provide a home in our intestines will provide us with molecules which keep our immune system vigilant and able to destroy pathogenic invaders such as the flu virus. However, we must feed them (and ourselves) the right food. This is the ultimate symbiotic relationship in an ecological system.
An integral part of staying well is reducing the total load of factors that damage health.
In this case, this includes toxic foods that are devoid of fiber and bioflavonoids etc. In addition, to reducing the total load, we must provide essential nutrients which we are unable to synthesize (Vitamins, D, A, C, Zinc, Selenium, etc.) so we and our microbiome can stay well even in the face of pathogen exposure and invasion.