The lunula—Latin for “little moon”—is the whitish half-moon at the base of the nail, above the cuticle. “It’s the visible part of the nail matrix, which produces the keratin that makes up the nail plate.” Its pale color comes from fewer blood vessels than the rest of the nail. Some people see it clearly, especially on thumbs, while in others it’s faint or absent—“age, skin tone, lighting conditions, and genetics all play a role.”

While variations are usually harmless, sudden or consistent changes can signal health issues. Enlarged lunulae may relate to “hyperthyroidism, high blood pressure, [or] cardiovascular strain.” Disappearing lunulae could indicate “chronic tiredness, iron deficiency, [or] vitamin B12 deficiency.” Color shifts—bluish, gray, or red—might reflect circulation, inflammation, or medication effects.

Nails mirror lifestyle: a visible lunula often shows a “nutrient-rich diet…balanced hormone function [and] manageable stress levels.” Fading can result from poor diet, stress, or hormonal changes.

Seek professional advice if lunula changes persist across multiple nails, especially with fatigue or pale skin.

The lunula is “a subtle but powerful messenger about your inner health.”