#2 Changes to the lunula
The majority of nails have a lunula, or white half-moon shape, at the base, right above the cuticle. It is the largest on the thumbnail and gets smaller as you go to the pinkie. Additionally, a change in the size or color of this area could be a sign of an underlying illness.
For instance, cirrhosis, chronic renal failure, or congestive heart failure may be indicated if the lunula reaches almost the end of the nail, turning the rest of the nail white aside from a narrow band at the top. Aging can also be the cause of this condition, often known as Terry’s nails.
A blue-tinged lunula may be a sign of Wilson’s disease, a rare genetic disorder where copper builds up in the liver, brain, and other organs. Research indicates that a red lunula may be a sign of heart failure. And half-and-half nails, in which the white from the lunula stretches halfway up the nail bed while the other half of the fingernail is darker in color, are quite common in people with severe kidney failure.
