Diet Changes Gut Bacteria Within a Day, Harvard Study Finds

A change in diet quickly alters the types of bacteria living in the human gut, a finding that suggests this rapid adaptability to different foods can be used to control illnesses tied to stomach microbes, researchers said.

Switching to an animal-based diet increased the number of microorganisms that process protein, while a plant-based diet increased the number of bacteria that help process starch and cellulose, according to a study led by Harvard University researchers published today in the journal Nature. The change in the bacteria populations occurred within a day.