What kids should know about how nails grow
You've had nails for a long time. In fact, you started growing nails before you were even born! Here are the different parts of your nails and how they grow:
The matrix: Each nail begins growing out of a little pocket under your skin. This is the root of the nail, and it's called the matrix. The matrix constantly makes new cells. These new cells force the old ones to get packed together and pushed up through the skin. By the time the nail pokes out of the skin (where you can see it), those cells are dead. That's why it doesn't hurt to cut your nails.
The cuticle: You might have heard about other parts of the nail, such as the cuticle. This is a tiny sliver of skin where your nail grows out of your finger. It protects the root or the matrix from germs.
The lunula: The small, whitish, half-moon shape that you sometime see at the bottom of your nails is called the lunula(pronounced loon-yoo-la). It's actually part of the matrix. You might be able to see it only on your thumbs, or maybe not at all. Don't worry if you can't see a lunula on any of your fingers. It's no big deal. It's there, just under your skin.
Some interesting facts about nail growth are:
Fingernails grow very slowly, and your toenails grow even more slowly.
A fingernail will take half a year to grow back if you lose one because of an injury. If you lose a toenail, it might take a year and a half to grow back!
Fingernails grow faster on your larger fingers and on your right hand if you're right-handed, and your left hand if you're left-handed.
Fingernails also grow faster during the day and in the summer.