Expert reveals why you should never go to bed with wet hair

Sleeping with wet hair could lead to unexpected problems.

Skin and hair experts agree that going to bed before drying your hair can lead to troublesome scalp issues — and even hidden bacteria in your bedsheets.

Briana Delvecchio, a hairstylist at Ashley Lauren Beauty Lounge in New York, shared in an interview with Fox News Digital that she always advises her clients against sleeping with wet hair for several reasons.

When hair is wet, the hydrogen bonds in the strands are temporarily broken, making it more elastic, fragile, and prone to breakage, she cautioned.

“Combine that with friction from your pillowcase, and it’s a recipe for split ends, tangles, and long-term damage,” Delvecchio said.

The scalp “also takes a hit,” she added, as a damp scalp trapped against a pillow overnight creates a warm, humid environment that’s ideal for fungal growth and bacterial buildup.

“This can trigger scalp irritation or dandruff, or even make your roots feel greasy by morning,” the hairstylist warned.

Sleeping with wet hair can also impact facial skin. “That moisture transfers to your pillowcase, which can harbor bacteria and oil that contribute to breakouts or flare-ups in sensitive skin,” Delvecchio noted. Dr. Noah Gratch, M.D., a board-certified dermatologist in New York, told Fox News Digital in a separate interview that he also recommends against sleeping with wet hair.

“While it’s not dangerous, there are dermatologic and hair health concerns associated with the habit,” he said. 

Friction against the pillow can exacerbate damage to fragile wet hair, leading to breakage and shedding over time, the dermatologist warned.

The damp environment can also contribute to scalp and skin issues, he agreed.

“A constantly damp scalp creates a warm, moist environment that can promote the overgrowth of Malassezia, a yeast that naturally lives on the scalp but can proliferate under these conditions,” Gratch said. 

“This may contribute to scalp conditions, such as seborrheic dermatitis (a chronic inflammatory skin condition) or dandruff.”

Sleeping with wet hair also increases the risk of developing folliculitis – a skin condition that causes irritation, inflammation, and bumps – or fungal infections in people with “already compromised skin barriers or oily scalps,” Gratch said.

The dermatologist reiterated that moisture trapped on the pillowcase can harbor bacteria, fungi, and dust mites.

“Prolonged skin contact with this moisture may contribute to acne flare-ups, particularly fungal acne, or exacerbate existing skin conditions like eczema,” he warned.

To avoid these complications, Delvecchio recommends towel-drying the hair and using a leave-in conditioner to protect the strands before bed, in addition to blow-drying on low heat or loosely braiding the hair once it’s mostly dry.

“A simple routine swap goes a long way toward keeping your hair, scalp, and skin healthy,” she added.