Skin and hair experts agree that going to bed with wet hair can have several health consequences. Briana Delvecchio, a hair stylist at Ashley Lauren Beauty Lounge in New York, says she always advises her clients against it for multiple reasons.

"When hair is wet, the hydrogen bonds within the hair shaft are temporarily broken, making it weaker and more prone to breakage," Delvecchio explains. "Combined with the friction from your pillowcase, this can lead to split ends, tangles, and long-term damage."

Not only does wet hair affect the hair itself, but it also impacts the scalp. According to Delvecchio, when a damp scalp is in contact with a pillow all night, it creates an ideal breeding ground for bacteria and fungus. This can cause irritation, dandruff, or make the roots of the hair oily by morning.

Sleeping with wet hair can also affect facial skin.

"The moisture transfers from your hair to your pillowcase, which already harbors bacteria and oil," Delvecchio says. "This can contribute to breakouts or exacerbate issues for those with sensitive skin."

Doctor Noah Gratch, a dermatologist in New York, also advises against sleeping with wet hair. He believes that while not immediately dangerous, the habit can negatively affect dermatological and hair health in the long run.

According to Doctor Gratch, wet hair rubbing against a pillow is prone to breakage. Additionally, prolonged scalp dampness allows the fungus Malassezia to overgrow, potentially leading to seborrheic dermatitis or dandruff.

Experts say sleeping with a wet head can lead to several health issues. Photo: Adobe Stock

Experts say sleeping with a wet head can lead to several health issues. Photo: Adobe Stock

He also warns of the risk of folliculitis, fungal infections, or acne due to prolonged contact with moisture on the pillowcase, especially for those with sensitive skin or overactive oil glands.

"Moisture can harbor bacteria, fungus, and dust mites, potentially worsening conditions like eczema or acne," he says.

To minimize these risks, Delvecchio recommends towel-drying hair, using a leave-in conditioner, and blow-drying on a low heat setting before bed. Braiding hair loosely when it is almost dry is also helpful.

"A simple change in routine can make a big difference in protecting the health of your hair, scalp, and skin," she adds.

A study published in the International Journal of Cosmetic Science also found that wet hair has higher elasticity and is more susceptible to damage from pulling or friction during sleep. This study emphasizes that allowing hair to dry naturally before sleeping not only maintains the hair's structure but also minimizes the risk of breakage and scalp irritation.