Graphic: Courtesy of Visible Productions

No matter how often you wash and sanitize, Dr. Oz says you can't get rid of all the bacteria growing on your skin. "Staph grows everywhere," he says. "It's in your armpits and all the folds."

Before you start scrubbing, remember that some types of bacteria are the "good guys" there to protect us from "bad guys" like MRSA.

If you're prescribed the wrong antibiotics to treat a bacterial infection, Dr. Oz says the good bacteria are killed, while MRSA lives on and begins to reproduce. "That cell loves it because it's not being killed," Dr. Oz says. "It starts to make the other cells around it become resistant to the other antibiotics that doctors like me would give."