As early as the fifth century BC, Hippocrates, a Greek physician who is widely considered to be the father of Western medicine, taught his students the importance of examining the patient’s fingernails. He wasn’t just looking for lapses in hygiene – Hippocrates believed that the fingernails reflect the condition of the inner body. He had discovered that abnormalities of the nails can provide clues about health conditions, both simple and more serious. In fact, he found that a certain deformity of the nail called “clubbing,” a.k.a. drumstick fingers, indicated inadequate oxygen in the blood, a sign of respiratory disorders. So important was this discovery that doctors, even today, often refer to clubbed fingernails as “Hippocratic fingers.”
If you’re skeptical that fingernail abnormalities could be an early sign of poor health, you have good reason to be, says Ramzi Saad, MD, a board-certified dermatologist at South Shore Skin Center and Spa in Massachusetts. Routine exams and lab testing might very well detect signs of illness prior to nail changes, but this is only if you visit the doctor. “If a person gets regular health care, this can show problems,” he explains. “But many people don’t go to the doctor regularly, so nails can be a good indicator of health conditions. Nails are at the end of your visual pathway. You can see your nails, but you can’t see your liver or kidneys.”
Why do fingernails reflect health problems? It’s not entirely understood, says Charles E. Crutchfield, III, MD, a board certified dermatologist practicing in the Minneapolis, Minnesota area. “However, in generalized inflammatory diseases, there is inflammation in the nail matrix (where the nail is being formed), and that can cause a weakness and pitting. And abnormalities in electrolytes and/or proteins in the blood can cause discoloration.”
If you examine your unpolished nails under a good light, you can get a good look at their color, shape and texture. Healthy nails are typically smooth, without ridges or dents. The area under the nail should be a uniform light pink without spots or discoloration. What nail symptoms might indicate health problems? Dermatologists weigh in on nail changes that might indicate a need for medical attention:
Terry’s Nails is a condition where the nail plate turns white and the lunula (the half moon at the base of the nail) disappears. It can occur in one or more fingers and is associated with hepatic (liver) disease.
Half and Half Nails, or Lindsay’s Nails, are characterized by the distal edge of the nail turning brown, dark red or pink. This is specific for underlying kidney disease. In more severe cases of kidney disease, the proximal part of the nail turns white.
Beau’s Lines may have been an olden day palm reader’s best friend. “When there’s a real bad systemic illness, shock, surgery or accident, the nail matrix will temporarily shut down and not produce nail,” Crutchfield explains. “Once it resumes, there’s a horizontal ridge that grows out with the nail called a Beau’s line. Because fingernails take six months to grow out, if the line on your fingernail is halfway down, you could tell the person, ‘Something very, very traumatic must have happened to you three months ago.’ And the person will say, ‘Absolutely. How did you know?’ ‘Well, because you can see that in the fingernail.’”
Splinter Hemorrhages are thin red or brown longitudinal lines that occur beneath the nail plate. They occur due to a clotting phenomena in the capillaries below the nail bed. While the hemorrhages or leaks may be due to nail trauma or other problems, they are a classic sign of endocarditis, an inflammation of the inner layer of the heart, especially when coupled with other signs of endocarditis, such as fever and chills.
Oil Drop Sign is a translucent yellow-red discoloration in the nail bed beneath the nail plate that resembles a drop of oil. “Once I see that, I need to know nothing else to know the patient has psoriasis,” says Crutchfield.
Clubbing is a change in the angle of the nail, a rounding of the nail bed. It can indicate a problem with oxygenation through the lungs, such as seen with smoking or chronic lung diseases, such as asthma, or chronic obstructive pulmonary disease. It can also be a sign of lung cancer.
Thickened, Rough Nails with crumbly debris under the tip of the nail usually indicates a fungal infection. While this can occur in people with normal immune systems, it may indicate an im-munodeficiency, such as occurs with HIV.
If you see any of these or other unusual nail changes, don’t panic – but do visit your physician for a check up. Fingernails usually are just one piece of the puzzle.