“I’ve had people ask me about this, and I can understand why they think it’s true,” says Dr. Hayley Goldbach, a dermatologist at UCLA Health. Some people start wearing a hat to hide hair loss, she says, which may lead observers to conclude it was the hat-wearing that triggered the baldness. That’s probably not the case. “I think the short answer is that [hat wearing] is probably not a real concern,” Goldbach says.

“Genetics are the main player in hair loss,” says Dr. Michael Wolfeld, a plastic surgeon specializing in hair restoration and assistant clinical professor at Mount Sinai Medical Center in New York City. Wolfeld says “male pattern” and “female pattern” baldness are both initiated in part by an inherited genetic sensitivity to a hormone called dihydrotestosterone (DHT), which turns up in the scalp as well as other parts of the body. Among people with this inherited sensitivity, hair follicles languish and shrink in response to DHT. Popular hair-loss therapies such as Propecia (finasteride) work by blocking the production of DHT, research has shown.