Updated: Jan 7, 2020
Everything you need to know.
Going gray is caused by a massive build up of hydrogen peroxide due to wear and tear of our hair follicles. The peroxide winds up blocking the normal synthesis of melanin, our hair's natural pigment.
"Not only blondes change their hair color with hydrogen peroxide," said Gerald Weissmann, MD, Editor-in-Chief of The Federation of American Societies for Experimental Biology Journal. "All of our hair cells make a tiny bit of hydrogen peroxide, but as we get older, this little bit becomes a lot. We bleach our hair pigment from within, and our hair turns gray and then white. This research, however, is an important first step to get at the root of the problem, so to speak."
The researchers made this discovery by examining cell cultures of human hair follicles. They found that the build up of hydrogen peroxide was caused by a reduction of an enzyme that breaks up hydrogen peroxide into water and oxygen (catalase). They also discovered that hair follicles could not repair the damage caused by the hydrogen peroxide because of low levels of enzymes that normally serve this function (MSR A and B). Further complicating matters, the high levels of hydrogen peroxide and low levels of MSR A and B, disrupt the formation of an enzyme (tyrosinase) that leads to the production of melanin in hair follicles. Melanin is the pigment responsible for hair color, skin color, and eye color. The researchers speculate that a similar breakdown in the skin could be the root cause of vitiligo.
What Causes Hair to Lose Its Color?
According to Cleveland Clinic, gray hair is hair with reduced levels of melanin. Melanin is the pigment occurring in the hair, skin, and eyes of humans, and varies in level from person to person. Genes definitely play a role as they help control melanin production.
Can Going Gray Be Prevented?
Unfortunately, for now, no. Researchers are examining possible links between stress, radiation exposure, inflammation and premature gray hairs, proposing that they may be responsible for destroying melanin stem cells. However, there is no conclusive proof to date on it. A 2013 study determined the link between smoking and premature graying: on average, smokers went gray three years earlier than non-smokers did. Otherwise, premature graying is largely genetic.