Here’s a media trend you’re guaranteed to notice next November: Lots of outlets will contrast current photos of President Barack Obama to pics of the president at his inauguration in order to illustrate how the stress of the job has aged him—or at least his hair. (George W. Bush and Bill Clinton’s manes got the same before-and-after treatment.) While being the most powerful person in the free world is undoubtedly a stressful gig, these stories don’t mention that pretty much every man in his 40s and early 50s undergoes a similar transformation.
“The way people are built, our hair is designed to have color for 45 or 50 years,” says Dr. Tyler Cymet, chief of clinical education at the American Association of Colleges of Osteopathic Medicine. While there’s some lingering debate about the underlying mechanism that causes hair to lose its pigment, most experts agree it has to do with your scalp’s color-producing cells—called melanocytes—switching off, according to Dr. Adam Friedman, an associate professor of dermatology and director of translational research at George Washington University.
For the average Caucasian, that switching off starts around age 35—give or take 10 years depending on your genes. The process begins a bit later for African Americans.
Your hair grows, hangs around, and falls out in cycles, each of which lasts anywhere from a few years to a decade, Cymet says. (These cycles don’t align, so some hairs are growing or in stasis even as others are falling out.) Once those first gray strands show up, more and more are going to appear with every new cycle. “Typically, if you’re 50% gray you’re going to be almost all gray by the end of the next cycle,” Cymet says.
And yes, stress can play a part in all this. There’s evidence stress may shorten the duration of your hair’s cycles, which would accelerate the spread of gray, Cymet says. Stress also creates systemic inflammation, which can switch off those pigment-producing cells, experts say.
“You see very young people with autoimmune disease who have patches of white or gray hair, and that’s because inflammation has turned off those melanocytes,” says Friedman.
Long story short, your hair (and probably the president’s) will naturally start graying sometime in your 30s or 40s, depending on your DNA. And if you’re perpetually stressed, the resulting inflammation can speed up your hair’s chromatic transformation.
The current presidential frontrunners are all well past their 60th birthdays. Unless a younger candidate makes a push—or a couple prominent candidates stop dying their hair—we’ll all have to go without those before-and-after pics when the next commander in chief leaves office.
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