Read more: What Happens If You Accidentally Eat Mold? Kefir has billions of live cultures in it, including 40 strains of bacteria that are good for your gut health. But that's also a lot of live ...

One way to increase the diversity of live bacteria in your gut is to eat fermented foods. Spector takes a shot of kefir every morning, along with home-brewed kombucha two to three times a week ...