Those things at the tips of your fingers--you call them fingernails--are made from the same structural building blocks as horses' hooves, bird talons, bear claws, and rhinoceros' horns, as well as hair and skin. No one is quite sure how these cells differentiate to form structures as diverse as the elastic outer layer of skin, the stiff scales of fish, or the softness of feathers.

As children, your fingernails and toenails grow an average of two inches per year. But as you age, your nails grow more slowly. The average adult fingernails grow about an inch in eight months.

The biggest enemies to healthy fingernails are overexposure to soap and water says Marta VanBeek, MD UI Dermatology. "Your nails, like your skin can dry out, so rub a thick skin moisturizer into your nails to keep them healthy, or you might consider wearing protective gloves."

If you use polish, the pigment and dyes in the polish can penetrate your nails so they take on a yellowish color. An occasional break from using nail polish can restore nails to their natural color.. In addition to nail polish, nicotine stain from smoking causes fingernails to turn yellow. If you use nail polish, use nail polish remover sparingly because the acetone can damage your nails.

Nail care tips:

• Keep nails clean and dry.
• Don't bite your fingernails.
• Cut your nails straight across and rounded slightly at the corners. Don't file them to a point. That makes them weaker.
• Use a fine textured file to keep nails shaped and free from snags.
• Eat plenty of protein and biotin which can be found in meats, fish, milk, and eggs.
• If you have an ingrown toenail, don't try to "dig it out" yourself, especially if your nails are already infected or sore.