Trivia 8 of 10
8. Fingernails grow faster than toenails
Fingernails grow about 3.5 millimeters a month, more than twice as fast as toenails. Replacing a whole fingernail takes about six months; a toenail takes over a year.
A factory hidden under the skin
The nail is produced in the matrix, an area hidden under the skin at the base of the nail. There, cells are made nonstop, fill up with keratin, the same protein found in hair, and push the nail forward.
A 2010 study measured growth in volunteers and found about 3.5 millimeters a month on the hands and 1.6 millimeters a month on the feet. The difference seems to be related to circulation and use: hands receive more blood and suffer more small impacts in daily life.
Other factors affect the pace. Nails tend to grow faster in young people and in hot weather, and more slowly with age. Since the nail keeps a record of several months, sudden changes in the body can leave lines that move forward along with it.
Hair follows a similar logic and is also made of keratin. It grows on average a little over 1 centimeter a month, and each strand goes through phases of growth, rest, and shedding.
Did you know? The white half-moon shape at the base of the nail, the lunula, is the visible tip of the matrix, the region that produces the nail.
