Your nails reveal a lot more about you than whether or not you take the time for a manicure. While not exactly the "windows to the soul" that eyes are said to be, your nails reveal a lot of information about your health.

Here are 11 clues to your health that are literally at your fingertips:

• Pitted nails. Nails with tiny ice-pick depressions that look like holes often indicate psoriasis, a skin disorder characterized by scaly or red patches on the skin. More uncommon causes could include the autoimmune disease alopecia areata, which causes hair loss, or a connective tissue disorder, such as Reiter's syndrome.

• Pale nails. Fingernail beds that are pale indicate anemia, a condition usually caused by low levels of iron, which leads to a low red blood cell count. However, they could also be early indicators of liver disease or diabetes.

• Clubbing. Low oxygen in nails can cause the tips of nails to enlarge and curve around the fingertips. It's associated with several types of lung disease as well as liver disease, heart problems, inflammatory bowel disease, and AIDS.

• Yellow, thick nails. Thick, yellow nails are usually the result of a fungal infection. Yellow nails, without thickening, could indicate serious pulmonary disease, such as chronic bronchitis, but yellow nails could also be stains from cigarette smoking or the result of using dark nail polish.

• Dark lines. Although dark skinned people can have darker, vertical lines in their nail bed, they can also be a sign of melanoma, a deadly form of skin cancer. Examine your nails regularly for changes, such as lines that change or darken, as carefully as you examine your skin.

• Spoon nails. Nails that looked scooped out leaving a depression indicates iron deficiency anemia or hemochromatosis, a condition where the body absorbs too much iron. Spoon nails can also indicate too little thyroid hormone, called hypothyroidism, or heart disease.

• Brittle, thin nails. Nails that frequently break and grow slowly can indicate your thyroid gland isn't producing enough thyroid hormone. A simple blood test can detect a thyroid condition which can be controlled with medications. But brittle nails can also be associated with aging or frequent, harsh manicures.

• White lines. Horizontal white lines if they cover the entire nail and are found on more than one finger are called Muehrcke's lines. They point to kidney or liver problems or to nutritional deficiencies.

• Blue nails. A lack of oxygen causes nails to turn blue, and indicates a lung disease. A more uncommon cause is a vascular condition called Raynaud's disease.

• Beau's lines. Horizontal indentations in the nail bed usually occur when nail growth is interrupted by illness or disease, such as pneumonia, heart attack, or uncontrolled diabetes. They can also indicate zinc deficiency.

• White spots. White spots are usually due to trauma, such as accidentally hitting your finger, and the problem will slowly disappear as the nail grows.