Question: Is It Bad to Sleep with Wet Hair?

“Always put on sunscreen,” “you should bring a jacket,” and “if you can’t say something nice, then don’t say anything at all.” Yep, mom knows best. But what about all those times she warned you about sleeping with wet hair? We investigate.

First of all, sorry mom, but falling asleep with a head of wet hair won’t actually give make you sick. Quick health class: The common cold is caused by a virus that has nothing to do with the temperature or dampness of your tresses. But that doesn’t necessarily mean you want to make a habit out of it.

That’s because your hair is weakest when it’s wet, which means that going to bed with water-logged strands could potentially damage the hair shaft. This may increase the likelihood of breakage and tangles. But keep in mind that the experts we spoke to stressed that occasionally crawling into bed with damp hair won’t cause much noticeable damage. Doing it every other night for weeks or months, however? Probably not such a great idea.

Per Phil Mania, owner of Mania Hair Studio: “Sleeping on wet, untreated hair can cause frizz, flyaways and possible breakage. Let your hair air-dry until it’s at least damp or use a hair dryer to quickly get some of the moisture out and apply a product that’s specific to your hair texture.” (Just remember to wash your pillow frequently to avoid product buildup.)

Another cautionary tale we’ve heard is that wet tresses can cause bacteria and mold to form on your scalp and pillow. But dermatologist Dr. Hal Weitzbuch tells us that this is just a theory without much proof. (Although, if you have allergies or scalp issues such as dandruff, then you should play it safe and dry your hair before bed.) “Basically, if you have gone to bed with wet hair and you don’t have a problem with it when you wake up, this shouldn’t be a problem for you moving forward,” says Weitzbuch.

Bottom line: Sleeping with wet hair every now and then isn’t going to do any serious damage. However, to minimize the risk of breakage (or if you have any concerns about your scalp or allergies), then you should let your hair dry before bedtime. But you know, don’t lose sleep over it.