Why does hair grow?
The Hair Factory
Why does hair grow?
Your hair is growing right now. Not fast enough to watch, but if you could see inside your scalp with a microscope, you'd witness thousands of tiny factories working around the clock, pushing new hair up through your skin like grass through soil.
Each strand of hair grows from a follicle — a small pocket in your skin shaped like a tube. At the bottom of that tube sits a cluster of cells called the root, and those cells have one job: divide and multiply. When a cell divides, it makes a copy of itself. The new cell pushes the old one up. The old cell gets shoved higher, hardens into a strand of hair, and you get a little bit taller on top.
