Is it true that sleeping with wet hair can make you sick? What are the facts behind this common belief?

We’ve all heard it: “Don’t sleep with wet hair, you’ll catch a cold!” But is there any science behind this age-old warning—or is it just a bedtime myth?

Here’s the truth: sleeping with wet hair doesn’t directly cause a cold. Colds are caused by viruses, not by temperature or dampness. You catch a cold when you’re exposed to germs—like rhinoviruses—not because your scalp is damp.

However, there’s a tiny catch. Sleeping with wet hair can make you feel colder, which may weaken your body’s defenses temporarily. If you’re already exposed to viruses, this slight drop in core temperature might tip the scales and make you more susceptible. But again, it’s not the hair—it’s the virus that causes illness.

What about your hair itself? That’s another story. Going to bed with wet hair can:

• Weaken hair strands, leading to breakage
• Encourage scalp fungus or dandruff if moisture gets trapped
• Cause morning frizz or tangles

So while it won’t give you the flu, it might mess with your hair health and comfort.

If you must shower at night:

• Use a towel to dry your hair as much as possible
• Switch to a microfiber turban or use a hair dryer on low heat
• Sleep on a silk pillowcase to reduce friction and breakage

Mom had a point—just not the one she thought.