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I’m at the doctor’s and my usual physician is on vacation, so they’ve sent me in to see a replacement to whom I believe Rachel from Friends would refer as “cute-boy doctor.” I’m 35, happily married, and reasonably sensible, all of which make it worse that I immediately feel my cheeks start to redden when he introduces himself to me, then spend my entire appointment distracted from my tonsillitis symptoms because I’m concerned that I look like a doll with huge pink cheeks drawn on.

It’s not an entirely unfamiliar feeling, this flush. I've always been prone to rosy skin. At its best, I like to think it lends me a Shakespearean modesty; “a maiden blush bepaint my cheek.” At worst, it feels like my face is on red alert, throbbing with heat and garnering all the wrong kinds of attention. And there always seems to be that one helpful soul happy to point it out. "Why have you gone red?"

Often, there's no answer to this question. I have blushed during inexplicably mundane conversations with postmen and bank clerks and shop assistants as well as with handsome medical types. Yes, sometimes I blush when I'm talking to boys I like—but almost as often I blush when talking to the ones I don't. Concentration, praise, and sudden attention all also can spark the slow-burning pink glow.

It’s something I’ve learned to live with over the years, but with this acceptance has come curiosity. Why do people blush? What does it mean? And what, if anything, can I do about it?

The science of blushing is straightforward, if not entirely comprehensive. Not much more is known now than it was when Charles Darwin first referred to blushing as “the most peculiar and most human of all expressions,” in The Expression of the Emotions in Man and Animals. Physiologically, blushing occurs when adrenaline causes the capillaries that carry blood to the skin to widen. Many scientists explain blushing in terms of the fight or flight response; people wear the stress of a difficult or confusing situation directly on their faces, in circumstances where throwing a punch or making a run for it aren’t feasible reactions.

For psychologist Ray Crozier, the small amount of information that is known about blushing simply raises more questions. “Blushing is a ubiquitous yet little-understood phenomenon,” he writes in “The Puzzle of Blushing.” “It is a visible change in our most conspicuous feature, yet it can occur when we least want to be noticed and, indeed, can draw attention to our behavior. We redden when we make a faux pas but also when we are praised or thanked. A blush is involuntary and uncontrollable—an actor might simulate a smile, laughter or a frown, but not a blush.”

Regardless of cause, blushing often does serve as a signal or a message to the outside world, Crozier points out—even if it’s a message a person may not be consciously choosing to send. This rings true to me: I see blushing as a loud-mouthed friend who insists on telling the world exactly what you’re thinking, and worse, often explains it badly. Yet in the literary world, at least, blushing’s ambiguity can be an incredibly useful device; a writer can paint a character’s face red and leave readers to figure out the meaning. Blushing appears in everything from Shakespeare, to the Romantic poets, to Rudyard Kipling, whose 17-year-old ingénue in “My Rival” “cannot check” her girlish blush, much to her annoyance.

Even Salman Rushdie in his (perhaps aptly-named) novel Shame includes a character whose “stinky blushes” are so hot they smell of petrol. “She’s a character he imagines as so responsive to the social pressure to blush for others that she blushes for the whole world, says Mary-Ann O’Farrell, the author of Telling Complexions: The Nineteenth-Century English Novel and the Blush. “But literary characters blush not only when they are embarrassed or ashamed but when they feel anger or pain or mortification, when they flirt, when they cover secrets and when they tell them, when they acknowledge love or try to deny that they are feeling it, when they feel the social pressure to behave well and when they notice someone else isn’t.”

In other words, blushing might be primarily an emotional message, but the variety of its content can vary from “I’m attracted to you” to “What dreadful manners you have!” Decoding these nuances is not always straightforward. Little surprise then that Jane Austen’s heroines are particularly prone to blushing, relying on their pink cheeks, in O’Farrell’s words, to “reveal things about themselves that would be difficult for them—living, as they do, in a highly-mannered world—to reveal in speech.”

Unsurprisingly, there’s a gendered element to this, as well. Blushing is not just a common response, but perhaps a desirable one for young ladies, insofar as it demonstrates their innocence—or the opposite. “If a woman is supposed to blush in the presence of a risqué remark, as the old conduct literature suggests, does her blush means she is innocent and mildly disapproving, or is she guilty of something by virtue of getting the joke?” O’Farrell asks.

Sadly, real-world blushers seem more likely to suffer from blushing’s impact on their lives. It’s not quite the social disaster that it was in the 1930s, when the theories of Viennese psychologist Ernst Bien linked red cheeks to necrophilia, repressed cannibalism, and even men’s vicarious desire to experience menstruation. But online forums devoted to blushing reveal many people for whom turning red is still a source of frustration and embarrassment, to the extent that the blushing has its own associated phobia: erythophobia, the fear of going red. For some people, blushing is a self-perpetuating cycle: The worry about blushing becomes precisely the thing that brings it on.

I spoke to one man who’s a frequenter of a blushing support forum, and he believes his life-long blushing has severely limited his ability to form relationships and progress at work. “I’m lucky to have a wonderful and understanding wife now, but for a long time blushing made it really hard to meet anyone,” he says. “People think it’s cute if you’re a woman, but just off-putting if you’re a man. I’m sure I’d be in a very different position in my career now if I didn’t feel I had to avoid any kind of public scrutiny. Even speaking up in small meetings makes me uncomfortable and anxious. And when I blush my face actively hurts.”

There are some treatment options. Hypnotherapy, counseling, and breathing exercises all have had some success in reducing blushing (or at least reducing anxiety about blushing, because it’s also often hard to be sure whether the turning red itself is the chicken or the egg). The most extreme modern solution is endoscopic thoracic sympathectomy, a surgical procedure where the nerves that cause the facial blood vessels to dilate are cut. It’s extremely effective—the success rate is 95 percent—but its potential side-effects include facial nerve damage and excessive sweating. This indicates exactly how serious the problem is for people willing to take the risk.

It’s not all bad news for people who frequently blush, though. In theorizing about what evolutionary advantages blushing might present, Darwin suggests turning red is a phenomenon that marks sensitivity in its sufferers. Infants don’t blush, he says, because “their mental powers are not yet sufficiently developed.” Blushing and shyness may not inevitably go hand in hand, but perhaps blushing and self-awareness do?

On a similar positive note, a study from the University of California, Berkeley, found that people who blush not only appear more generous and trustworthy, but actually may be more generous and trustworthy. The researchers asked 60 students to recount embarrassing moments and rated them according to how many signs of embarrassment they showed, including blushing. Afterward, when the students were given 10 raffle tickets to keep or share as they chose, it turned out that those who blushed more were also more likely to share their tickets than non-blushers.

For me, acceptance has been the key in coming to terms with my own status as a blusher. There’s a comfort of sorts in keeping company with a long line of literary heroines, and my husband, at least, always says he was first attracted to me because of a certain glow. It’s not the most painless flirting technique ever, but it has on occasion proved a useful one.

“There’s a moment in Jane Austen’s Emma when her heroine, Emma Woodhouse, blushes and laughs at the same time when she catches herself doing something,” O’Farrell says. “Those of us who blush a lot—I admit it!—can sometimes take a little pleasure, as Emma does, in that moment of being caught.”

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