My third favorite X-Man is a character named Rogue. If you don’t know, her power is siphoning the powers away from anyone she touches. Rogue’s trademark is a big shock of white hair right in the middle of her brown mop. Depending on where you get your X-myths (comics, cartoons, movies), this bit of premature gray came from either kissing a boy named Cody, choking out Ms. Marvel, or soaking up some of Wolverine’s healing factor. Whatever it was, the experience traumatized her, bleaching her bangs.

Stories of stress turning hair gray abound in popular culture, from Marie Antoinette’s hair turning white the night before her beheading, to Barack Obama’s rapid first-term graying. But, is there actually a mechanism in your body that translates anxiety into silver locks?

Scientists have looked into it, but despite several promising results they haven’t yet nailed down a solid link. In fact, they aren’t exactly sure what causes hair to turn gray in natural aging. What they do know is that it has something to do with the pigments that give your hair its hue.

Hair color comes from two naturally occurring pigments, called melanins. Eumelanin produces the darker shades, from brown to black. Gingers and towheads get their shining locks from pheomelanin. As you age, something interferes with these pigments. But, what could that be?

There are two prevailing hypotheses. The first is that aging wears down your DNA, somehow inhibiting the production of the cells called melanocytes that produce melanin. Most of the studies supporting this hypothesis have been done in mice, however, and so far haven’t closed in on a complete explanation of how this would work.

The second hypothesis says that your hair gets bleached from within, rather than depigmented. The culprit is hydrogen peroxide, the same stuff you used in 10th grade to complete your “Eminem” look. Your follicles make it in small amounts, but normally this bleaching compound is kept in check by another enzyme called catalase. A 2009 study showed that catalase production falls off as we age, letting hydrogen peroxide build up and whiten your hair. It’s another intriguing hypothesis, but there still isn’t enough evidence to back it up.

Scientists have no idea how stress would prematurely trigger either of these processes. The best, and most recent, answer goes through a different pathway—your body’s fight or flight response. When you get stressed or anxious, your body turns on its sympathetic nervous system, causing your heart to beat faster, your body to tense up, and your senses to heighten. It’s basically like when KITT from Knight Rider goes into Super Pursuit mode, and is great for short bursts of focused effort.

However, maintaining this state is pretty bad for your body. In 2011, a team led by Nobel Prize winner Robert Lefkowitz showed that the negative effects of prolonged stress reach all the way into your DNA, affecting genes that control hair pigment.

But even this link hasn’t been totally confirmed. That would take longer, broader studies conclusively linking cause and effect. This means someone would have to convince an ethics board to allow purposefully put a group of volunteers into prolonged states of panic. Good luck with that.

But even though there’s no conclusive link, you should still try to avoid getting stressed out. Lefkowitz’s 2011 study also showed that stress was linked to a miscarriages, premature aging, and a variety of cancers.

You may not be able to stave off your unpaid bills, nagging ex, or impending deadline, but you can address some of the behavioral baggage that accentuates your anxiety. When stressed, you tend to eat worse, exercise less, drink more, and toss and turn through the night. Tack on that stone face expression and hunched shoulders, and you’ve added muscular tension to the mix. Start the process by giving yourself some quiet time. Research has shown that even ten minutes of controlled breathing, or mindfulness, can lower your heart rate, blood pressure, and breathing, as well as increase circulation to your skin.

So maybe there’s no definite link between stress and gray hair. Marie Antoinette might have already been gray beneath her wigs, and President Obama’s first term happened to fall right around those silvering late 40’s. But, if fear of turning gray gives you reason to manage your anxiety, I’d say keep on believing. Just don’t stress yourself out about it.

Oh, and in case you were wondering, my second favorite X-man is Blink, and number one is Nightcrawler. Neither has a touch of gray, maybe because they have the power to teleport away from their problems.