The Online Library of Knowledge

LET'S EXPLORE The human body

What are hair and nails made of?

A human hair with 70 times magnification A human hair with 70 times magnification Both hair, which feels quite soft, and nails, which feel hard, are made of the same chemical substance. This is called keratin. It also forms the tough outer surface of the epidermis, the upper layer of skin. And just like the surface of your skin, your hair and nails are mostly made up of dead cells.



A greatly magnified view of hairA greatly magnified view of hair


 

A cross-section through a hair follicleA cross-section through a hair follicle

Hair

Most of a hair, including the shaft that is visible above the skin, is made of dead cells. The living part of a hair is found at its root. This is fixed deep inside a pit in your skin, called a follicle. A tiny muscle is attached to each follicle. In cold weather, these muscles pull the hairs upright. This makes the skin bunch up around the hairs to form goose pimples. For our hairy ancestors, this helped to keep them warm. 

Each hair follicle will produce about 8 metres (26 feet) of hair over the course of a lifetime.

© 2019 Q-files Ltd. All rights reserved. Switch to Mobile