what causes grey hair?

Answer 1

The stem cells of hair stops producing melanin (natural pigment) therefore the hair turns transparent. They seams to be gray because it get mixed with other colored hairs.
The stop of melanin producing can be caused by age, stress, smoking and some others factors that i can remenber right now.

Answer 2

Gray hair is typically a result of natural aging. Pigment in the hair shaft comes from special cells at the root (base) of the hair. These cells are genetically programmed to make a certain amount of pigment (melanin) at specific ages. At some point in the aging process, these cells make less and less pigment until the hair has very little pigment. White hair has no pigment, and gray hair has some but not as much as a red, black or brown hair.

Not all hairs respond in the same way or at the same time. So the graying process usually is gradual. You can't prevent graying. Some people start graying in their 30s, and some not until their 60s. Genetics likely play a strong role in graying.

People rarely go gray overnight. If they do, it's typically due to alopecia areata. This condition causes the thicker, darker hairs to stop growing before it affects the growth of gray hairs — giving the impression of graying overnight. Alopecia areata eventually

Answer 3

"If you've got 'em, flaunt 'em!"

Personally, I have been going gray since I turned 17. I've always loved it. Back then, it was a sign that I was getting older. Now, I just feel that just like I've earned every laughline, I have likewise earned each and every gray hair, and I embrace them. When my grandmother died at nearly 92, she had less gray hair than her son--my father. In fact, in their 70's, both of my parents are only salt and pepper, rather than true gray. So, more than likely, I will not get my wish for a full head of silver or white hair. Shucks!

Sometimes, however, people dealing with illness or a great deal of stress can go grey rapidly. I believe that their condition is causing the otherwise natural progress
to speed up. Therefore, it appears that they turn grey almost "overnight."

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According to answers.com, grey hair is caused by the following:

"Effects of aging on hair color

An elderly man with grey hairA change in hair color typically occurs naturally as people age, usually turning their hair from its natural color to gray, then to white. More than 40 percent of Americans have some gray hair by their fortieth birthday, but grey hairs can appear as early as the teens and twenties for some, or even in childhood. The determination of when someone begins graying, whether it comes with aging or prematurely, seems to be almost entirely based on genetics. Sometimes people are born with gray hair because it is passed down genetically.

The change in hair color is caused by the gradual decrease of pigmentation that occurs when melanin ceases to be produced in the hair root, and new hairs grow in without pigment. Two genes appear to be responsible for the process of greying, Bcl2 and Mitf. The stem cells at the base of hair follicles are responsible for producing melanocytes, the cells that produce and store pigment in hair and skin. The death of the melanocyte stem cells causes hair to begin going grey.[2]

There are no special diets, nutritional supplements, vitamins, nor proteins that have been proven to slow, stop, or in any way affect the graying process, although many have been marketed over the years.

Many people use hair dye to disguise the amount of gray in their hair.

A 1996 British Medical Journal study conducted by J.G. Mosley, MD found that tobacco smoking may cause premature graying. Smokers were found to be four times more likely to begin graying prematurely, compared to nonsmokers in the study.[3]"
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There are other answers from MayoClinic.com, AskYahoo.com, 101lifestyle.com, DisabledWorld.com, and VirtualHairCare.com.
Please check the links below.

Answer 4

Grey hair is caused by the body inability of the body to manufacture pigment cells. Although, teenagers are a close second. ;)

Answer 5

age

Answer 6

age

Answer 7

stress, genetics, lack of pigment in the hair. and age.

Answer 8

Divorce attorneys.

Answer 9

All I can think of is stress/aging

Answer 10

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