A reporter struggling to meet a deadline. A single mother juggling work and kids. A student cramming for exams. Could any of these folks justifiably fault their harried lifestyles when they notice a few gray hairs?
While we've all blamed our fading locks on stress, in reality, there is no proven link, said Jeffrey Miller.
"Hair grays when cells stop producing the color pigment, melanin," said Miller, associate professor of dermatology in Penn State's College of Medicine. "It's a natural part of the aging process."
There are three phases to the hair growth cycle, Miller explained: anagen, catagen and telogen. During the anagen or active stage, hair grows rapidly. Each strand grows for two to four years before entering the catagen phase, a transitional state. After about two weeks, hair reaches its final resting point, the telogen stage. After several months of rest, the inactive older hairs are pushed out by new hairs. "The telogen hairs are those that you find in your comb or at the bottom of the bathtub," said Miller. "The average person loses 50 to 100 of these strands during daily activities."
"As we age, each cycle gets shorter and shorter," described Miller. "And, in turn, the shortened cycles accelerate the breakdown of melanin." The faster hair falls out, the quicker pigment cells stop working.
Melanin is found in skin, eyes and hair. The amount of pigment produced by melanocyte cells determines color. Brunettes have more melanin than blondes, and white hair has no melanin at all. "Gray hair is a mixture of pigmented hair and white hair," Miller noted.
"The process normally begins in one's 30s, but gray hair may become visible as early as one's teens," said Miller. When it starts has much to do with genetics, he noted. "Look at your father, your mother, your siblings. If they went gray early, chances are that you will, too."
While Americans spend billions of dollars every year on hair dye products to cover gray, the breakdown of melanin is difficult to reverse. "Some medical treatments like radiation therapy have unexpectedly caused gray patients to go dark again," said Miller. "Scientists can't explain it, but researchers, especially in the cosmetic industry, are searching for an answer to the connection."
As for blaming the stress of daily life for the gray strands, Miller noted that there is limited research in the field. "Stress is an engineering term," he explained. "And the medical community does not yet fully understand its effect on the body."
Going gray is a natural part of growing old, and Miller advises adults to embrace the change. After all, 30-year-old singer Taylor Hicks didn't let his premature gray prevent him from winning "American Idol." Meryl Streep shook her silver locks with confidence in The Devil Wears Prada. So the next time someone notices another gray hair in the mirror, call it stylish salt-and-pepper or a badge of wisdom, and wear it with pride.
Source: By Emily Rowlands, Research Penn State
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