Every day, you lose about 50 to 100 hairs. You've seen them.
They swirl down the drain in the tub or get stuck on the back of
your sweater. Or, worst of all, one might get in your mouth.
Gross. Normally, when hair falls out, new hairs start forming in
the same place as the old ones. But when someone has hair loss,
the hairs may not grow back. Or they do grow, but there aren't
enough of them to take the place of what's already fallen out.
This often happens to men, who might start to go bald as they
get older. But anyone can have hair loss, even kids. The medical
name for hair loss is alopecia (say: al-uh-pee-shuh). The Hair-y
Story The hair on your head is made of keratin (say: kair-uh-
tin), the same protein that makes up your nails. Hairs grow from
follicles (say: fahl-ih-kulz), which are very tiny holes deep in
your skin. Each follicle contains a hair root, the part of the
hair that is alive and growing. The part of the hair you can
see, the part above the skin, is dead. (That's why it doesn't
hurt to get a