Dr. Oz's Beauty Book

One of the largest contributors to people feeling unattractive has nothing to do with their looks, but their breath. Dr. Oz says it can often be a sign of a serious health problem, but many people don't know they have bad breath since it's hard to smell yourself. "If someone comes up to you and gives you a mouth freshener, they're telling you you have bad breath," he says. "They're not being kind." 

Bad breath is often caused by stomach issues—bacteria or foods that don't agree with you. "Another common cause, besides gingivitis, is your tongue," Dr. Oz says. He suggests buying a tongue scraper to clean off bacteria and fight bad breath. "Don't ignore bad breath. Something is going on in there, which is why you've got that stench."