Diet Pills

Even though they may seem like a quick way to trim your waist, diet pills can also be a fast track to gum disease and tooth decay. Like many over-the-counter and prescription medications, diet pills decrease salivary flow, which causes dry mouth and puts you at risk for gum disease, tooth decay, cavities, and discomfort. Bottom line: A balanced diet and exercise are the safest way to lose weight and protect your smile.

Teeth Grinding

Teeth grinding, or bruxism, can affect your jaw, cause pain, and even change the appearance of your face. Stress and anger can increase nighttime teeth grinding. Finding ways to alleviate these feelings can help, but it's also important to see your dentist, who can recommend solutions like a custom night guard.

Sugar and Your Teeth

Contrary to what mom said, sugar won't directly rot your teeth—but the acid produced when you eat sugar and carbohydrates can. Naturally occurring bacteria in the mouth devour sugar, creating acids that attack tooth enamel, which can lead to decay and a host of other problems, including gingivitis and cavities.

The worst thing you can do is leave sugar lingering on your teeth and gums. Eating any amount of candy and brushing and flossing immediately is actually less damaging than not brushing after eating one piece before bedtime.