Ingrown toenails occur in both men and women. According to the National Health Services (NHS), ingrown toenails may be more common in people with sweaty feet, such as teenagers. Older people may also be at higher risk because toenails thicken with age.
Many things can cause an ingrown toenail, including:
cutting toenails incorrectly (Cut straight across, since angling the sides of the nail can encourage the nail to grow into the skin.)
irregular, curved toenails
footwear that places a lot of pressure on the big toes, such as socks and stockings that are too tight or shoes that are too tight, narrow, or flat for your feet
toenail injury, including stubbing your toe, dropping something heavy on your foot, or kicking a ball repeatedly
improper foot hygiene, such as not keeping your feet clean or dry