What Are The Causes Of Graying Hair?

As you age, your body performs cell production and cell processes at a slower rate than usual. Hair that falls out takes longer to return. Skin that once lasted hours in the sun now burns easily. Similarly, the melanocytes, or the cells that produce skin and hair color, no longer function like they used to. As a result, your hair grays as you get older, varying according to genetics, nutrients and the impacts of environmental toxins.

Hydrogen Peroxide Production

A Feb. 23, 2009, article in the Federation of American Societies for Experimental Biology suggests that graying is the result of hydrogen peroxide production that accompanies normal hair growth and development. Research shows that as you reach a certain age, catalase--the enzyme responsible for decomposing and removing excess hydrogen peroxide--weakens and allows for an accumulation of hydrogen peroxide to build beneath the scalp's surface. With time, this bleaches hair cells, causing a whitening effect that can appear gray during earlier stages.

Heredity

Although scientists disagree on which side of the family contributes most to early graying, it appears that gray hair occurs earliest for whites, then Asians and blacks, according to the "Journal of Investigative Dermatology Symposium Proceedings." A family history of early graying signals the likelihood of gray hair affecting you at an earlier age, with a history of tuberous sclerosis and neurofibromatosis increasing your odds. By age 50, half of Caucasians experience some form of graying.

Skin Ailments

Because hair follicles closely resemble the production of skin cells, any skin disorder or disease should have some effect on hair growth. In fact, DrGreene.com says thyroid conditions, disorders of skin pigmentation such as vitiligo, and viral illnesses that attack melanocytes can all contribute to unnatural graying. Nevertheless, these causes are rare and limited to a select group of people.

Nutrient Deficiency

Any deficiency of vitamin B12 can disrupt hair production, triggering the increased appearance of gray hair--although this is highly unlikely. Unless you follow a strict vegan diet, are malnourished or have an enzyme disorder, you should get enough vitamin B12 from a single serving of any animal-based food product.

Genotoxic Stress

Despite the common folklore, psychological stress doesn't lead to early graying. However, environmental toxins may deform your genetic coding, creating what's referred to as genotoxic stress. In a June 12, 2009, edition of Cell magazine, researchers explained that UV light and other forms of radiation may poison melanocytes and hair cells, causing a decreased production of hair pigment. Scientists have only studied the effects on animals, but the research suggests the possibility of the same stress causing graying in humans.