Is Going to Bed With Wet Hair Bad for You?

Ever hear that going to bed with wet hair will make you sick? You’re not alone. It’s one of those pieces of old-school advice that gets passed down from generation to generation, along with the thought that plucking one gray hair causes three to grow back and that only teenagers get acne.

Some people prefer to wash their hair at night for whatever reason—it fits with their schedule, they love that snooze button or they’ve been doing it for years without really thinking about it. But does going to bed with wet hair really, truly, actually make you sick? And even if it doesn’t, does it harm your hair? We went to the experts to find if the advice actually holds up—or not.

Ask the Doctor: Will Going to Bed With Wet Hair Make You Sick?

According to Amber Tully, MD, a family-medicine physician at Cleveland Clinic, the idea that sleeping with wet hair can cause illness is an old wives’ tale. (Sorry, mom.) The common cold—think sniffling, congestion or a runny nose—is caused by a virus that is in no way related to how damp or dry your hair is. “You may feel physically cold if you sleep with wet or damp hair, but this will not cause illness,” says Dr. Tully. But people associate being sick with feeling physically cold, she explains, which is probably why this mistake is so prevalent.

On the other hand, going to bed with wet hair can cause an entirely different set of issues—for your scalp. “A chronically damp or wet pillow may become a breeding ground for bacterial or fungal infections, since the combination of warmth and moisture allows many fungal elements to thrive,” says Dr. Tully. That could result in seborrheic dermatitis—a.k.a. dandruff, the most obvious sign of which is a chronically red, itchy or flaky scalp.

Ask the Hairstylist: Will Going to Bed With Wet Hair Damage Your Hair? 

Going to bed with wet hair can also create extra work in the AM. “Sleeping with wet hair causes your hair to set, which means your hair will turn out whichever way you sleep on it,” says Marshall Lin, a stylist at Frédéric Fekkai SoHo Salon. “Your hair can get tangled during sleep, and those knots can be harder to get out without causing breakage to strands.” He also seconds the point about damage to the scalp—noting that it’s not just your pillow that’s the problem. “The moisture, oil and body heat from your scalp can cause buildup and lead to dry scalp or dandruff,” he says.