Causes of Premature Gray Hair

Silvery strands are one of the more conspicuous signs of aging. That said, getting gray hair doesn't necessarily mean you're closer to the end of your life span than anyone else your age.

Early gray hair may not mean anything other than your genetics are kicking in. Different people gray at different rates—and that's normal. However, graying can happen for other reasons as well, including stress.

Here's how and why graying hair happens, plus what you can do if you want to potentially reverse it.

What Causes Gray Hair

Gray hair comes down to melanin, or rather the lack of melanin. Melanin is the pigment that gives hair its color. It also determines your eye and skin color—and it's why you get freckles.

Scientists believe the stem cells that mature to become melanin-producing cells may wear out, become damaged, or lose the support systems meant to keep them working. The factors listed below may also cause hair to change color:

• Age
• Body distribution
• Climate
• Chemical exposure
• Genetic defects
• Hormones
• Pollutants
• Toxins

White Hair vs. Gray Hair

The cells that produce melanin are called melanocytes. The melanocytes that give your hair its color are found in the hair follicle, where a strand of hair grows.

Over time, melanocytes produce less and less melanin and eventually stop producing it entirely. The lack of melanin causes your hair to lose its color. Gray hair has reduced melanin, while white hair completely lacks it.

What Causes Premature Graying

If you think you're going gray unusually early, there are several possible reasons why. It could be due to your ethnicity or your lifestyle and environment.

Your age and ethnicity will help determine whether you fall into the category of premature graying. Here's when you would be considered to have early grays based on your ethnicity:

• Whites: before age 20
• Asians: before age 25
• Blacks: before age 30

Smoking may cause gray hairs to show up earlier than you hoped. The longer you smoke, the more your risk of premature graying increases.

Environmental factors—like ultraviolet rays and air pollutants—could be partially to blame.

Stress is another possible reason for gray hair. Researchers examining gray hair have suggested that "free radicals"—damaging chemicals caused by stress, smoking, inflammation, or radiation exposure—might be responsible for destroying pigment-producing melanocyte stem cells.

A June 2021 study in Cell Biology from researchers at Columbia University Vagelos College of Physicians and Surgeons found evidence linking psychological stress to graying hair in people.

In rare cases, premature graying can be a sign of a medical issue, such as vitiligo (a condition that causes the skin to lose its pigmentation), pernicious anemia (in which the body has difficulty absorbing vitamin B12), or problems involving your pituitary or thyroid glands.

Genetic Causes

Some genetic diseases can also cause premature graying:

• Albinism: This group of genetic conditions causes people to be born with light-to-white-colored skin, hair, and eyes. Again, melanin is to blame—or, rather, a lack or absence of this pigment.
• Chédiak-Higashi syndrome: This rare immune disease can cause fair skin and light-colored hair that may have a metallic look and other health conditions.
• Griscelli syndrome: This rare condition appears in infancy and includes light-colored skin and other abnormalities. Elejalde disease seems to be a form of Griscelli syndrome.
• Waardenburg syndrome: Signs of this condition include a white patch of hair above the forehead and a lack of skin pigmentation.

Check with your healthcare provider if you have concerns about premature graying.

Can It Be Reversed?

All the worrying over encroaching grays can cause stress, which may speed up graying and could even cause hair loss. If you're just starting to see grays, there's good news: Research shows once your stress has been eliminated, your hair may return to its original color, at least temporarily.

If you've been gray for a while, you likely won't see your hair reverting to its former color by reducing stress levels. Graying is a natural aging process; eventually, you reach a point when it can't be reversed. Regardless, you can still reap other health benefits when you keep your stress in check.

A Quick Review

As you age, your hair slowly starts to lose melanin—the pigment that gives hair its color. Gray hairs show up at different times in people depending on age, ethnicity, stress, and other factors.

Genetic diseases can cause graying or whitening of the hair but tend to be relatively rare. People who are just starting to go gray may see some color return by reducing stress levels. Otherwise, graying is a natural part of aging, and, at some point, it can't be reversed.