Heat Of The Moment

Can you guess what’s sneakily, quietly aging your skin? You’re getting warmer....

- Katie Becker

Something very odd was going on. Women in Saudi Arabia were getting the kinds of dark spots on their cheeks that are normally caused by the sun—only that should have been impossible. “They were wearing niqabs, which are traditional Muslim face coverings, so their skin was hardly ever exposed,” says Zoe Diana Draelos, a consulting professor of dermatology at Duke University, who researches hyperpigmentation. “Discoloration never should have been an issue for them.”

A world away, on the Upper East Side of Manhattan, another bizarre phenomenon: “Spin instructors and women who were taking hot yoga upwards of five times a week were getting more discoloration and persistent redness than other patients,” says Doris Day, a clinical associate professor of dermatology at NYU Langone Medical Center in New York City. They were slathering on sunscreen religiously, but it wasn’t making as much of a difference as you’d expect.