According to Mary Ellen Camire, associate professor of food science and human nutrition at the University of Maine, Orono, eating dried blueberries can relieve diarrhea. Apparently, certain compounds found in blueberries, like tannin, stop the proliferation of bacteria associated with diarrhea. It is important to remember, however, only dried blueberries can alleviate diarrhea; blueberries that are either fresh or frozen may actually compound the situation.