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Skin Health

Your Nails and Your Health

Although we often think of nails primarily in terms of cosmetics, they often reflect a number of health conditions. According to the American Association of Dermatologists, changes in the nail, such as discoloration or thickening, can signal health problems including liver and kidney diseases, heart and lung conditions, anemia and diabetes. And nail growth is affected by nutrition, fever, chronic illness and aging.

Nail problems make up about 10% of all dermatological conditions, and about half of that number is caused by fungal infections. These are more common in toenails, the AAD says, because the toes are confined in a warm, moist, weight-bearing environment.

Although rare, melanoma, the deadliest form of skin cancer, can grow under the nail. Such melanomas may be mistaken for an injury, so a dermatologist should be consulted if a dark-colored streak appears within the nail plate, if the nail discoloration does not gradually improve, or if the size of the streak increases over time.

The AAD lists other common nail problems:

White spots after an injury to the nail.

Vertical lines, known as splinter hemorrhages, under the nails caused by nail injury or certain drugs or diseases.

Bacterial infections, most often due to injury, poor skin hygiene, nail biting, finger sucking, or frequent exposure to water.

Ingrown toenails, caused by improper nail trimming, poor stance, digestive problems, or tight shoes. The AAD cautions against self-treating toenails, especially if they are infected.

In general, the association says, nail problems are more frequent if you have diabetes or poor circulation. They recommend seeing a dermatologist if you spot a problem.


Keep nails clean and dry to prevent bacteria from collecting under the nail.

Cut fingernails and toenails straight across and rounded slightly in the center. This keeps your nails strong and helps avoid ingrown toenails.

When toenails are thick and difficult to cut, soak feet in warm salt water (one teaspoon of salt per pint of water) for five to 10 minutes, then apply urea or lactic acid cream. This softens the nails, making them easier to trim.

Wear proper-fitting shoes and alternate shoes on a regular basis. Tight shoes can cause ingrown toenails.

Do not bite your fingernails. You can transfer infectious organisms between your fingers and mouth. Also, nail biting can damage the skin around your fingers, allowing infections to enter.

Apply a cream to moisturize your nails, especially after removing nail polish;  most removers contain chemicals that dry the nails.

If you want to wear a bright red or orange polish, prevent discoloration by applying an extra layer of base coat. If your nails become yellowed and discolored from the polish, they should return to normal color over several weeks if the same color is not reapplied.