Grey hair has very little melanin, while white hair has no melanin at all. As you go through the aging process, your hair might turn grey before going completely white. For some, this process is so drastic that the hair simply turns silver and then white.
Genetic factors, stress, hair dyes, and other factors may contribute. The human body has millions of hair follicles or small sacs lining the skin. The follicles generate hair and color or pigment cells that contain melanin. Over time, hair follicles lose pigment cells, resulting in white hair color.
In time, everyone's hair turns gray. Your chance of going gray increases 10-20% every decade after 30 years. Initially, hair is white. It gets its natural color from a type of pigment called melanin.
Scientists still don't know why some people turn gray early, late, or not at all, although they suspect genes, nutrients and possibly the immune system play a role in depleting melanocyte stem cells.
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. As people continue to get older, fewer pigment cells will be around to produce melanin.
Gray hair comes down to melanin, or rather the lack of melanin. Melanin is the pigment that gives hair its color. Gray hair has reduced melanin, while white hair completely lacks it. This occurs because of a gradual decline in the number of stem cells that mature to become melanin-producing cells.
Blonds get white hair just like brunets, but some blondes only appear to get a lighter blond while others experience their blonde hairs getting darker and duller as the white hairs begin to appear. Still, blondes can, over time, have a full head of white hair.
"This is a predestined thing—it's genetic and can happen at any age." With that said, she cites the late thirties as the time at which pubic hair typically begins to gray. Some health factors, however, may accelerate the graying process, says dermatologist Joshua Zeichner, MD.
"People usually notice their first grey hairs in their early 30s," says Anabel, "and on average, over half of our hair will be white (unpigmented) by our 50s. However, women and men can begin to turn grey as early as 18, while others experience their first white hairs much later in life," she adds.
Gray hair is one of the universal signs of advanced age. More likely than not, at some point in your life, your hair will start to go gray. Some individuals can maintain hair color well into their older age, but most do not.
Most people start noticing their first gray hairs in their 30s—although some may find them in their late 20s.This period, when graying has just begun, is probably when the process is most reversible, according to Paus.
A new study shows that stress really can give you gray hair. Researchers found that the body's fight-or-flight response plays a key role in turning hair gray. Your hair color is determined by pigment-producing cells called melanocytes.
"While it's a natural part of aging for most of us, not everyone automatically turns gray when they hit the age of 50," she says. "Some people in their 80s don't have gray hair yet, while others get white hair in their late teens," she adds.
However, the rate of hair colour loss is largely determined by your genes. The chances are that you will experience premature greying if your parents do. However, certain nutritional deficiencies and underlying medical conditions may play a role. In these cases, yes, white hair can turn black again.
While the study concluded that the average age for a woman to go grey is 33, it found redheads lose their colour at 30, brunettes at 32 and blondes at 35.
Don't assume that grey hair makes you look older
Hair naturally loses pigment as we age, but stylist Paul Falltrick points out that the notion that grey hair makes you look older is increasingly becoming a misnomer: "Grey shades can be stereotyped as ageing, but a clean-looking grey is stunning" he says.
However, vitamin B12 may give you the appearance of fuller and thicker hair because the increase in oxygen to hair follicles can help stimulate the replacement of lost strands. Vitamin B12 may also help give your hair an overall healthier appearance since intake of enough B12 is responsible for stronger hair shafts.
Premature graying may be reversed with vitamin B12 supplementation only if vitamin B12 deficiency is the cause. If you are graying due to other factors, such as genetics, zinc deficiency, and medications, your gray hair cannot be reversed.
The hair follicles contain melanin. As people age, these follicles begin to die off, and there is less melanin in the hair. As the follicles die and melanin decreases, the color of the hair fades to silver, gray, or white. This process happens with hair all over the body, including pubic hair.
Pubic hair and hair on the body doesn't usually grow back after the menopause, this is due to levels of estrogen and progesterone remaining low as we continue to age.
One of the many facts about redheads is that their hair will never turn grey. The pigment in their hair that causes it to be red will just fade over time, causing their hair to turn blonde or white, but never grey.
As of today, there does not seem to be any correlation between the various hair colors vs. the rate of hair turning grey.
THE SKIN on the temples is derived from facial skin and as the face develops some of the skin is left up on the temples. Thus the hair on the temple goes grey when the facial hair (ie, a beard in a male) goes grey rather than when the hair on the head goes grey.