Does sleeping with wet hair really cause a cold?

For generations, parents and grandparents have warned children against going to bed with wet hair, insisting that it could lead to a cold or fever. But science tells a different story: wet hair itself does not cause a cold or flu.

According to Dr Neeraj Kumar, senior consultant in internal medicine at Sharda Care Healthcity in India, common colds and influenza are caused primarily by viral infections, not by sleeping with wet hair.

“There is no scientific basis to suggest that simply having wet hair will suddenly make someone sick,” he said.

That, however, does not make sleeping with wet hair a particularly healthy habit. Prolonged dampness can affect the scalp, hair quality and overall sleep comfort, particularly for people prone to scalp conditions.

A wet scalp can remain warm and humid for extended periods, creating conditions that may encourage the growth of fungi and bacteria. People who already suffer from dandruff or seborrheic dermatitis may be more likely to experience increased itching, flaking and redness.

Wet hair is also more vulnerable to damage. When hair absorbs water, its fibres swell, leaving the strands weaker and more prone to breakage. Friction against a pillow during sleep can then contribute to hair breakage, tangling and loss of smoothness, potentially leaving the hair dry and dull over time.

The moisture from wet hair can also transfer to pillows, where prolonged dampness may contribute to the accumulation of dust and microorganisms. This could aggravate allergies or cause skin irritation in some people.

For individuals who are particularly sensitive to cold temperatures, sleeping with wet hair on a damp, cool pillow may also contribute to discomfort, including headaches or neck stiffness.

Dr Kumar recommends drying the hair thoroughly before going to bed. If that is not possible, he suggests gently pressing the hair with a towel to remove excess water and, if necessary, using a hair dryer on a low or moderate heat setting.

Wet hair should not be tied tightly before sleeping. Keeping it loosely arranged can reduce tension and breakage. Using a silk or satin pillowcase can also help minimise friction between the hair and pillow.

Regularly washing pillowcases and drying them properly, preferably in sunlight, is another simple way to maintain a cleaner sleeping environment.

So, while wet hair may not give you a cold, going to bed with it soaking wet may still be bad news for your scalp, hair and sleep comfort.