How does gray hair happen?
Each hair on our heads is made up of a few basic parts:
* a shaft - the colored part we see growing out of our heads
* a root - the bottom part, which keeps the hair anchored under the scalp
The root of a strand of hair is surrounded by a tube of tissue under the skin that is called the hair follicle. Each hair follicle contains a certain number of pigment cells. These pigment cells continuously produce a chemical called melanin that gives the growing shaft of hair its color of brown, blonde, red, and anything else nature decides.
Melanin is the same stuff that makes our skin's color fair or darker. It also helps determine whether a person will burn or tan in the sun. The dark or light color of someone's hair depends on how much melanin each hair contains.
The closer the pigment cells are together, the darker the hair/skin color. If there are very few cells, you have a blonde. Many large cells packed closer together - dark brunette.
As we get age, the pigment cells gradually stop producing. When there are fewer pigment cells in a hair follicle, that strand of hair will no longer contain as much melanin and will become a more transparent color - like gray, silver, or white - as it grows.
People can get gray hair at any age. Some people go gray at a young age - as early as when they are in high school or college - whereas others may be in their 30s or 40s before they see that first gray hair. How early we start to get gray hair is determined by a few factors - genes, stress, and health. Your maternal grandfather's hair is the one to access (especially for men worrying about hair loss).
Gray hair is also more noticeable in people with darker hair because it stands out, but people with naturally lighter hair are just as likely to go gray. From the time a person notices a few gray hairs, it may take more than 10 years for their entire hair to change.