Chipping, peeling, and smoothness are probably the first things you think of when it comes to fingernail health. However, your nails don’t just tell you how well your nails are doing: They might be able to tell you something about your entire body.
Any change in shape, texture, color, and even strength in the nail could be a warning sign for health problems or diseases, according to the American Academy of Dermatology (AAD). Some may signal a relatively minor nutritional deficiency, while others may point to a medical emergency (see “blue nails”).
These are some of the most common nail color changes to know about, according to the AAD:
White nails are known as “Terry’s nail,” which is when the half-moon at the bottom of the nail (known as the lunula) takes up almost 80 percent of the nail, according to a 2016 article from Journal of General Internal Medicine. This change in nail color could be a symptom of type 2 diabetes, heart failure, or a liver disease (like hepatitis C).
Pale nails are a telltale sign of iron-deficiency anemia. This condition means the body is low on healthy red blood cells due to inadequate intake of iron—which helps make red blood cells—according to the U.S. National Library of Medicine.
Half-pink, half-white nails are called “Lindsay’s nail” and are often associated with kidney disease. The lunula takes up a little more than half of the nail bed, and the remaining band at the top is a reddish-brown color.
This color change is linked to a higher concentration of the β-melanocyte-stimulating hormone. This hormone is involved in the production of melanin (the pigment in your skin).
Yellow nails are one of the most common fingernail color changes. Sometimes, the yellow nail completely obscures the lunula. Most of the time, it is linked to a fungal infection, but it may also hint at a lung disease or rheumatoid arthritis. Yellow-tinted nails can also be a health effect of smoking.
Blue nails are called cyanosis, and it won’t just affect the nails: The skin may turn a blueish gray all over. This bizarre hue change may signal that the blood circulating in the body is lacking oxygen. It’s often accompanied by shortness of breath.
In dark skin tones, cyanosis is more visible in the nails and mucous membranes—the lips, gums, and eyelids—than the rest of the skin, according to the U.S. National Library of Medicine.
A red lunula (the half-moon at the bottom of the nail) looks alarming, and it can be a symptom of a number of diseases, many of which are autoimmune or inflammation-based diseases:
A blue lunula may be the most confusing nail color change of all. It may simply be a side effect of certain medications, such as hydroxyurea (which is used to treat sickle-cell disease).
Blue lunulae are also a sign of argyria—a type of poisoning caused by excessive silver exposure. Argyria may cause a grayish, purple discoloration all over the skin.
Your fingernails aren’t the only clue to health problems: