gut microbiota. In particular, people who ate a diverse diet that was rich in healthful plant-based foods and healthful animal-based foods, such as oily fish, had high levels of health-promoting, “good” microbes in their gut.“Given the highly personalized composition of each individual[‘s] microbiome, our research suggests that we may be able to modify our gut microbiome to optimize our health by choosing the best foods for our unique biology,” says Dr.