10 nervous habits that are bad for your health

Nervous habits are usually more annoying to the people around you than to yourself, but some types of fidgeting and fussing can do real harm. Here, on Fox News channel, the experts reveal the reasons why nail-biting, hair-twirling, and other seemingly harmless habits can be hazardous to your health.

You bite your nails

It's one thing if you nervously bite your nails only during scary movies, but when it becomes a regular habit, it can damage both your nails and the skin around them, said Dr. Michael Shapiro, a New York City-based dermatologist. Germs from the mouth get transferred to the skin, and vice versa. "Bacteria under the nails may also be transferred to mouth, causing infections of the gums and throat," Shapiro said.

Painting your nails may discourage you from chewing. Try tape to break the habit.

You twirl and pull your hair

Twisting and twirling a piece of hair around your finger can lead to damage to the root over time, said Dr. Ariel Ostad, a dermatologist based in New York City.

"This can result in temporary or permanent areas of hair loss as well as infection," Ostad said.

Obsessive hair pulling may be a sign of a psychiatric impulse control condition called trichotillomania, which requires psychotherapy and medication.

You crack your neck

Twisting your head forcibly to one side releases gases built up in the the joints between vertebrae and creates a popping sound. Although this may feel good, repeatedly cracking your neck can make the surrounding ligaments hypermobile and more susceptible to injury, said Dr. Michael Gleiber, a board-certified orthopedic surgeon and affiliate assistant professor at Florida Atlantic University's Charles E. Schmidt College of Medicine.

You touch your face

Repeatedly touching your face or picking at acne can damage the top very thin microscopic layers of the skin, said Dr. Jessica Krant, board certified dermatologist and founder of Art of Dermatology and assistant clinical professor of dermatology at SUNY Downstate Medical Center in New York City.

"Treat them gently with topical creams and plenty of moisturizer," she said.

You grind your teeth

Clenching and grinding your teeth (bruxism) when you're under stress can wreak havoc with your oral health. Grinding can cause teeth to crack or break, which may require repair with crowns or root canals. It can also result in damage to the jaw joint in the form of temporomandibular joint disorder (TMJ), said Justin Philipp, who has a dental practice in Chandler, Ariz.

You suck on hard candies

Sucking on hard candies bathes your teeth in sugar, which can lead to cavities, says Philipp. Bacteria feed off the sugar, which creates a perfect environment for tooth decay. ucking on candies in moderation is fine provided the candies are sugarless and low in acidity

You lick or bite your lip

Nervously licking your lips exposes them to your mouth's digestive enzymes, said Dr. Whitney Bowe, a New York board-certified dermatologist.

"These enzymes chew away at the skin and can lead to dermatitis and cheilitis (inflammation), which make lips appear dry and cracked," she said.

Biting your lips when under stress can cause the development of fibromas, firm flesh colored growths, that may require surgical removal, says Coyle S. Connolly, MD, dermatologist and president of Connolly Dermatology in New Jersey.

You gnaw on the inside of your cheek

Over time this can result in chronic inflammation, possible bleeding, and scarring of the area.

You chew gum

All that snapping and popping does more than annoy your coworkers. It may also put you at risk for TMJ from overuse of jaw muscles, Philipp said. Sugarless gum presents a different set of problems, mainly digestive ailments. Sorbitol, an artificial sweetener, produces an unpleasant laxative effect when eaten in excess (18 to 20 sticks a day). Swallowing excess air while chewing also increases risk of a gassy stomach, according to the National Digestive Diseases Information Clearinghouse (NDDIC).

You nibble the ends of pencils and pens

Germs can lurk on the ends of pens so this habit can expose you to nasty pathogens including cold viruses, said Ted Myatt, director of research compliance at the University of Rhode Island.

And aside from the embarrassment of ink on your mouth from an exploding pen, chewing on writing instruments can damage teeth and dental work as well as injure the soft tissue and gums inside the mouth.

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