Why The Corners Of Your Mouth Crack — & How To Fix It

Just like chapped lips, it's easy to associate the development of dry, crusty patches on the corners of our mouths with exposure to extreme cold and dryness. But it turns out that those flaky patches of skin anchoring our smiles aren't just an extension of dry, irritated lips gone rogue — and they're not cold sores, either. Rather, they come courtesy of a condition called angular cheilitis, which can stick around for weeks when left to heal on its own.

Not only are the scabs not particularly cute, but they turn things that should be pleasurable into painful tasks, like biting into a big, juicy burger or, uh, smiling. That's not exactly the kind of thing we're willing to put up with for weeks on end, so we talked to three experts — a dentist, a dermatologist, and a nutritionist — to help us understand how to shorten that hellish healing time, and prevent new outbreaks from happening in the first place.

The first thing to know about angular cheilitis is that it’s perfectly normal. The condition is so common, in fact, it’s taught on day one of dermatology school, says S. Manjula Jegasothy, M.D., a Miami-based dermatologist. That’s because these annoying little sores stem from something as simple as drool (which, of course, is something we all do — and not just over the brothers Hemsworth). “Yeast is always present in the mouth and saliva, so when we drool in our sleep, it collects in the corners of the mouth, like rain in a gutter,” Dr. Jegasothy explains. This buildup of yeast causes dry, red flakes of skin to form. “Because the grooves in the corners of our mouth get deeper as we age, this can worsen the older we get,” she says.

Though these painful sores can be more likely to form in colder climates, the weather itself isn’t exactly to blame. For one, something as innocuous as dry indoor heating systems or a stuffy nose can cause us to sleep with our mouth open, Dr. Jegasothy says, making the corners of the mouth a perfect destination for traveling drool. As cosmetic dentist Brian Kantor, DDS, of New York’s Lowenberg, Lituchy & Kantor points out, overzealous lip licking can also lead to angular cheilitis (which makes us wonder if Cher or LL Cool J feel our pain, too?). “A person may lick their lips more in an attempt to soothe the pain or dryness of their lips,” he says. “This excess saliva will sit in the corners, which is the perfect warm environment for fungus like yeast to grow. Viruses and bacteria can also cause it to develop."

But that’s not all: Dr. Kantor also says those who regularly have oral thrush (also known as oral candidiasis, a yeast infection that develops on the inside of the mouth and tongue) or inflammatory illnesses, or take prescription drugs such as oral retinoids, corticosteroids, or antibiotics, are more susceptible to developing these corner sores. Those who wear wear braces or smoke, or live with anaemia, diabetes, or cancer may also see the condition more frequently. Ditto for those who have an overhang of the upper lip, something that creates deeper angles at the corners of the lips.

Diet can also play a part. "A nutritional deficiency of B2, B3, B6, and iron can increase the risk of developing angular cheilitis," says Maya Feller, a New York-based registered dietitian and nutritionist who specialises in nutrition for chronic disease prevention. "High-carbohydrate diets, as well as glucose-rich diets, can also provide an environment where oral candidiasis can thrive.”

If these raw, uncomfortable sores stem from yeast, wouldn’t the logical move be to simply blast the stuff from our saliva with some sort of super mouthwash? Not quite, says Dr. Kantor. “Candida is normal in the saliva and you don’t want to eradicate it completely, as it would disturb the normal flora of the mouth,” he says. “No mouthwash could or should be used to kill all of the candida in the mouth. Mouthwash also won’t help or hurt the angles of the mouth when you rinse.” To help keep our oral health and a yeast takeover in check, the dentist suggests maintaining good oral-hygiene habits: brushing twice a day, flossing, and rinsing with an antiseptic mouth rinse.

As Feller notes, more common-sense self-care, like rounding out your diet, can also help balance healthy flora in the mouth — something that may lead to fewer instances of corner sores. “From a nutritional standpoint, I would recommend following a balanced diet that provides an abundance of whole and minimally-processed foods including both non-starchy and starchy vegetables, legumes, and fruits,” she says. “For those at risk, such as those with a B vitamin deficiency, anaemia, or diabetes, it's important to make sure that the gastrointestinal system is not compromised and that the body is absorbing all the foods and or supplements they are taking.”

If angular cheilitis rears its ugly head even in the face of best practices, Dr. Jegasothy has one last — and somewhat surprising — line of defence. “Any over-the-counter athlete’s foot cream with butenafine 2%, like Lotrimin Ultra, will help,” she says. Never mind that the stuff may be built for the body part furthest from your face: Twice daily (morning and night) application of the antifungal medicine can regulate and diminish the sore, she says. The reality is that drool happens — even for those who practice all the good sense dietary, oral, and skin-care habits in the world.