The microbes in your body that you couldn't live without

Vitamin source

You probably didn’t think you’d see escherichia coli on this list, but some strains actually hold therapeutic value. “Among the beneficial things you’ll find in the body are certain strains of E. coli in our digestive tracts, which help control and keep dangerous bacteria at bay, and produce K and B complex vitamins, which the human body is unable to manufacture enough of on its own,” says Taft.