White spots on your fingernails? Calcium deficiency! Longitudinal grooves? Wrong manicure! Brittle nails? Biotin helps! – None of that is true. There are all sorts of myths surrounding fingernails, which are actually a simple part of the body. A research team from Fulda University wanted to know what is really behind spots and grooves. And above all, whether our fingernails can be used to find out how healthily we eat.

She was attracted to a special property of the dead matter at our fingertips. It’s a kind of diary: Skin cells on the nail bed harden into keratin and advance three to four millimeters per month, storing minerals and trace elements from the body. Couldn’t you tell how healthy someone is and how balanced their diet is – without any blood tests? They only ever show a snapshot. The fingernail, on the other hand, is an archive.