Nail-biting health issues

Biting your fingernails doesn’t only make your nails look bad. It can also make you feel bad.

Time magazine readers asked whether biting your nails was dangerous or just gross. The magazine went to the experts, who said nail biting is dangerous for a number of different reasons.

Nails harbor germs, in particular a family of bacteria that includes salmonella and E. coli. The bacteria thrive in the crevice between the finger and the nail, Dr. Richard Scher, an expert on nail disorders at Weill Cornell Medical College, told Time.

When you bite your nails, those bacteria end up in your mouth and gut, where they cause gastrointestinal infections that come with all sorts of lovely symptoms.

Long-term nail gnawing can lead to tears or abrasions in the skin of your fingertips where strains of bacteria or yeast get inside. Both can cause swelling, redness and puss under the nail, which has to be drained surgically and treated with antibiotics or antifungal medication, Scher told Time.

Nail biting can also cause dental problems.

“Constant biting can lead to poor dental occlusion, so the biter’s teeth shift out of position or become oddly shaped,” Scher said.

Biters also suffer from higher rates of gum disease and infection, he added.

So for the sake of your nails – and your health – stop biting those nails.

Marissa Harshman

Marissa Harshman

I'm the health reporter for The Columbian newspaper in Vancouver, Wash. I started at The Columbian -- my hometown newspaper -- in September 2009. Reach me at or 360-735-4546.

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