know your body: what your nails say about your health

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nail abnormalities can include a curling or clubbing of the nail, spoon nails, white spots and swelling.

by nick beare

published jun 22, 2021

last updated feb 21, 2025

2 minute read

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2 minute read

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consult with a doctor or dermatologist if you are concerned about any nail abnormalities. getty

like all primates, humans evolved with fingernails — the flattened remnants of claws — to aid in the protection of our fingertips. we might not be spending much time in the trees, but most primates require a strong, durable grip to manoeuvre from branch to branch, especially since they don’t have claws like other animals.

humans actually have wider fingertips than our closest relatives like chimpanzees and orangutans when you account for size. some believe we evolved that way to be able to pick up large objects like rocks, as it became less important for us to scramble up trees to survive.

these days, well-kept fingernails are more about aesthetics than grabbing that next tree branch — though they do help with daily motor functions such as scratching and picking things up.

while important for everyday purposes, fingernails are also a window into potential health conditions. they might turn different colours, bend in odd ways or develop ripples, bumps and lines, clues of potential issues with the heart, lungs, liver or a variety of other bodily functions.

here’s a look at the connection between health and our nails.

do we really need fingernails?
humans don’t need fingernails to live. however, life would be much harder without them. according to one study, the tips of our fingers would actually start to bend backward if our nails weren’t so strong.

“it is generally agreed that nails serve as a stiff backing to the soft terminal pads, preventing the skin at the ends of the finger and toes from rolling backwards,” the researchers wrote.

fungal infections
proper nail care can help to avoid most fungal infections and nail-related issues. according to healthline, fingernails should ideally be “pink at the nail beds, slightly rounded, with small, shallow vertical lines.”

a fungal infection is one of the most common issues associated with fingernails. you are more likely to develop a fungal nail infection if you have diabetes, are over 65, wear artificial nails, have a weakened immune system, or have a disease that causes poor circulation, according to the mayo clinic.

fungal nail infections are also contagious, and you can catch them from someone else with an infection. some symptoms might include yellowing of the nail, a nail that starts to lift off the nail bed, an odour emitting from the nail, brittle or hardened nails.

fungal nail infections should be diagnosed by a doctor to make sure there aren’t other health issues involved. the infections can be treated effectively with antifungal medication.

other health risks
fingernails can take on many different forms when there are other health problems present. white nails with dark rims can be a sign of a liver problem like hepatitis. rippled nails can indicate psoriasis. and frequently cracking or splitting nails can be caused by a thyroid problem.

other nail abnormalities can include a curling or ‘clubbing’ of the nail (clubbing nails is a symptom of many different conditions), nails that turn concave or ‘spoon nails’ (iron deficiency, heart disease and others), white spots, transverse lines and depressions. swelling, bleeding, pain and changes in thickness can also occur.

although most nail abnormalities are harmless, it’s important to know some of the signs that there may be a more serious underlying issue. consult with a doctor or dermatologist if you are concerned.