There are some things we’ve heard over and over again to the point that we’ve accepted them as universal truths: Never pop a pimple, for one (up for debate); Jennifer Lopez doesn’t age, for another (fact). Falling somewhere between J.Lo and pimple-popping is sleeping on wet hair. When we were younger, our mothers chided us for doing this, fearing we’d catch a cold. Now that we’re older, it still somehow feels wrong—like our hairstylists would slap us on the wrists if they found out. Tired of living with the guilt, we decided to put an end to the debate once and for all and go straight to our favorite sources: science and a trustworthy hairstylist. Keep scrolling to see what we found!
On catching a cold…
The whole idea of getting sick from sleeping on wet hair stems from the idea that you catch a cold from physically being cold. But as any scientist will tell you, the common cold is a virus, which means it has nothing to do with the temperature of where you happen to be—supposedly. There have been a number of studies examining whether temperature affects your body’s likelihood to get sick, with inconclusive results. However, one study seemed to link the two, according to BBC. A researcher named Ron Eccles asked half a group of volunteers to sit with their feet in a tub of cold water (the equivalent of having a head of wet hair); the other half sat with their feet in an empty tub and kept their socks and shoes on. In the first few days, there was no difference. However, four to five days later, twice as many people in the first group said they had shown cold symptoms.
So what does this mean exactly? One theory is that when your body gets cold, the blood vessels in your nose and throat constrict, which allows fewer virus-fighting white blood cells to get through. However, the subjects only described having cold symptoms and weren’t tested to determine if they actually had the virus. The link between temperature and getting sick is murky at best—play it safe by sleeping on wet hair only when you’re in a warm, comfy bed.
On ruining your hair…
On the other side, what about the actual health of your hair: Can sleeping on it wet affect that? We took our query to celebrity hairstylist John Ruggiero. “It’s not a good idea in the sense that it’ll dry funny and be unruly and knotty when you wake up, causing more work for yourself in the morning,” he says. If you insist on sleeping on wet hair, Ruggiero suggests employing a few precautions. “I would tell my client to comb through with a little leave-in conditioner or a detangling spray, loosely braid her hair, then put it into a bun on top of her head,” he says. “That way it’ll stay untangled and have a great wave in it when she wakes up.” (Here are some more ways to sleep on wet hair without hating your life.)
Shop some of our favorite leave-in products below.
This offering from Kevin Murphy is light enough for even finer hair types and comes in a convenient spray bottle. It provides deep moisturization plus strengthening and restorative benefits, and it works as an effective detangler. To top it off, it even smells amazing.
Designed to be applied to hair prior to going to bed, this overnight mask replenishes and hydrates strands as you sleep. It provides shine and nourishment for up to five days between shampoos. Wash it out or use it as leave-in for easier styling come morning.
Formulated with 16 different essential oils, this unique oil-cream product is suitable for all hair types and loved by men and women alike. Apply it to damp or dry hair for hydration, frizz control, and increased shine.
This product promises 10 different benefits in one—like nourishment, manageability, shine, and heat protection. The cream formula is lightweight and absorbs quickly, so your hair is never weighed down or greasy.
A blend of argan oil and hemp oil make this product a supremely nourishing experience for dry, lackluster hair, while calendula and green tea work to revive the scalp between shampoos. The result is glossy, renewed hair that is easy to manage and perfect for everyday styling.
This story was originally published November 11, 2015, and has been updated by Hallie Gould, with additional reporting by Liliane Kelly.