The nails, like the skin from which they are derived, are a portion of the integumentary system. This system helps to protect the person from invasion by bacteria and viruses outside the body. Nails are a type of skin that is harder and located over the ends of the toes and fingers. While they are not necessary for life, nails can make life easier by facilitating gripping, scratching, and picking up very small objects. Nails are also good for getting leverage in small spaces such as under a piece of paper.

Many times, the nails can be used as a diagnostic tool of long term ailments of the body. Since nails take a long time to grow, only those infections and incidences of malnutrition which occur over many weeks or months will have visible evidence in the structure of the nails. Anemia or circulatory problems might be evidenced by very pale or bluish nails. A severe, long term iron deficiency can be spotted by nails which curve upward in a concave shape. Up to ten percent of the time, psoriasis is first seen in pitted nails and then spreads to the rest of the skin after that. Very dark lines beneath the nail bed could be a red flag for skin cancer. Anyone concerned about the appearance of their nails should visit their physician to rule out more serious systematic infections.

The nails themselves can also fall prey to infection. One of the most common is a fungal infection. This can result in yellow, brittle nails. Treatment is possible to alleviate the condition; it will not remedy itself. The use of antifungal oral or topical medications can help to kill the fungus causing the problem. Psoriasis not only affects the skin, but the nails as well. A physician can offer a patient suffering from nail psoriasis few options other than to ease the symptoms. If the nails are pulling up and causing problems for the patient, their removal might be suggested.

All parts of the body work together to keep a person healthy, and as with any other part of the body, when an infection invades, the nails can change. Changes in the nails should be discussed with a physician to get prompt treatment and find the underlying cause which may or may not be more serious.