Many people assume that going gray is unavoidable. However, recent research from the French Government Institute, Paris Hospital, and the Phytosolba Laboratory has been exploring whether it’s possible to restore our natural hair color as we age—and perhaps even reverse some signs of time. In doing so, they’ve uncovered some surprising factors behind premature graying. And here’s a spoiler: hair dye might be part of the problem.
It all revolves around melanin, the body’s natural pigment responsible for the color of our hair, eyes, and skin. Everyone has melanin in varying amounts and combinations, which not only makes each of us unique but also offers added benefits like protection from UV radiation and sun damage. It may even support the immune system and help reduce inflammation.
Melanin—or the lack of it—is also what causes gray or white hair. While aging naturally slows or stops melanin production in hair follicles, lifestyle factors like stress and diet can affect it too. But according to this research, there’s more to the story.
Melanin and Hair Follicles
Hair actually starts growing white inside the follicle. As it develops, pigment-producing cells called melanocytes release melanin, which colors the strand. When a follicle ages or becomes damaged—slowing or halting melanin production, or causing the pigment cells themselves to deteriorate—new hair grows out without pigment, appearing white or gray.
How Hair Dye Affects Follicles
This is where it gets interesting: the research indicates that a buildup of hydrogen peroxide inside the follicle can contribute to white hair. When hydrogen peroxide accumulates, it oxidizes melanin, stripping the strand of pigment and leaving it white.
So what is hydrogen peroxide? Dr. Priscilla Wu of Ching-Yi University’s Department of Cosmetic Science explains that hydrogen peroxide (H₂O₂) is a highly reactive oxidizing compound, often stored as a 30%–60% solution. In hair coloring, stylists use products containing hydrogen peroxide or similar bleaching agents to lighten pigment.
If hair is frequently bleached or dyed with peroxide-based formulas, excess hydrogen peroxide can build up in the follicle. Over time, this oxidative stress may increase the likelihood of gray or white hairs. So if you’re dyeing your hair to cover grays, you might inadvertently be encouraging more to grow.
Too Much Sun
Free radicals can also cause hair follicles to oxidize prematurely—meaning everything from sun exposure to pollution can accelerate aging. UV rays from the sun generate free radicals that damage melanocytes, while airborne pollutants like particulate matter, heavy metals, and ozone create oxidative reactions on the scalp and around the follicle. Both of these stressors can disrupt melanin production, inflame the follicle, and speed up the loss of pigment-producing cells.
It’s one more reason to wear a hat outdoors—and perhaps reconsider peroxide-based hair dyes.
Curious about a beauty or wellness trend? We’d love to hear from you! Email Vogue’s senior beauty & wellness editor at beauty@vogue.com.
Frequently Asked Questions
Frequently Asked Questions Why Some People Go Gray Sooner Than Others
Basics Definitions
Q What exactly causes hair to turn gray
A Hair turns gray when the pigmentproducing cells in your hair follicles called melanocytes slow down or stop producing melaninthe pigment that gives hair its color
Q Is going gray just a normal part of aging
A Yes for most people it is Its a natural biological process but the timing of when it starts and how quickly it progresses varies greatly from person to person
Q What does premature graying mean
A Premature graying is typically defined as having significant gray hair before age 20 for people of European descent before age 25 for people of Asian descent and before age 30 for people of African descent
Causes Factors
Q Is going gray early mostly determined by genetics
A Yes genetics is the strongest factor If your parents or grandparents went gray early youre more likely to as well Scientists have even identified specific genes linked to the timing of graying
Q Can stress really turn your hair gray
A While chronic severe stress may accelerate the graying process by affecting stem cells in hair follicles its unlikely to be the sole cause The saying about worrying yourself gray has some scientific backing but genetics still plays the lead role
Q Do lifestyle choices like smoking or diet affect it
A Yes Smoking is strongly linked to premature graying likely due to oxidative stress damaging melanocytes Deficiencies in certain vitamins and minerals may also play a role in some cases
Q Can a medical condition cause early graying
A Certain conditions like vitiligo or autoimmune diseases can sometimes be associated with premature graying Thyroid imbalances and vitamin B12 deficiency are also known contributors If graying is sudden or patchy its wise to consult a doctor
Q Does race or ethnicity influence when you go gray
A Yes on average People of European descent tend to gray earlier while people of Asian and African descent tend to start graying later often in their