This talk explores how the modernization of global diets has reduced food diversity and displaced fermented foods, contributing to rising rates of chronic disease. Drawing inspiration from traditional Japanese diets, the research focuses on fermented foods and their impact on gut health and immunity. The speaker highlights the discovery of bioactive, bioavailable cyclic dipeptides in certain Japanese fermented foods, which enhance immune cell function while reducing harmful inflammation. The work suggests that affordable, traditional fermented foods can play a powerful role in supporting immune health and preventing disease.