Fingernail moons are the rounded shadows at the base of your nails. A fingernail moon is also called a lunula, which is Latin for little moon. The place where each nail begins growing is known as the matrix. This is where the new cells are made that will make up the nail. The lunula is part of the matrix.
Not being able to see your fingernail moons doesn’t always mean that something is wrong with your health. Sometimes, you may only be able to see lunula on your thumbs, or possibly not on any fingers at all. In these cases, the lunula is most likely hidden under your skin.
Though the connection is not completely understood, an absent lunula can indicate anemia, malnutrition, and depression. Make an appointment with your doctor if you’re experiencing any of the following symptoms along with an absence of lunula:
- lightheadedness or dizziness
- unusual cravings, such as dirt or clay
- loss of interest in your favorite activities
- significant weight gain or weight loss
Azure lunula describes the phenomenon where the moons of the fingernails take on a blue discoloration. This may indicate Wilson’s disease, also known as hepatolenticular degeneration. Wilson’s disease is a rare inherited genetic disorder that causes an excess amount of copper to accumulate in the liver, brain, and other vital organs.
Symptoms other than azure lunula that occur in Wilson’s disease include:
- lack of appetite
- abdominal pain
- jaundice (yellowed skin)
- golden-brown eye discoloration
- fluid buildup in the legs
- problems with speech
- uncontrolled movements
Pyramidal lunula occurs when the moons of your fingernail form in a triangle shape. Most often, this is caused by an improper manicure or another kind of trauma to the fingernail. The moons may stay this way until the nail grows out and the tissue fully heals.
Moons that are red in color, called red lunula, can indicate a number of different conditions which may significantly affect your health. Red lunula can appear in those with:
- collagen vascular disease
- heart failure
- chronic obstructive pulmonary disease (COPD)
- chronic hives
- carbon monoxide poisoning
These conditions should be treated by a doctor, so contact your doctor if you develop lunula with red discoloration.
In most cases, having no moons on your fingers isn’t a sign of something serious. However, if you’re not seeing moons, or if you’re seeing changes to the shape or color of your moons along with other symptoms, you’ll want to visit your doctor. They’ll make sure you don’t have an underlying health condition that needs to be treated.