10 Nervous Habits That Hurt Your Health

twirl-hair
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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, says Ariel Ostad, MD, a dermatologist based in New York City. "This can result in temporary or permanent areas of hair loss as well as infection," Dr. Ostad says. Obsessive hair pulling may be a sign of a psychiatric impulse control condition called trichotillomania, which requires psychotherapy and medication. Related: 21 Reasons Why You're Losing Your Hair

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