Is it ever okay to sleep with wet hair?

If you shower before bed, you’re probably a wet hair sleeper. It's convenient, it's fuss-free and when worn in braids, gives you the type of near-perfect curl pattern only a professional or a whole load of arm ache can achieve with heated tools. But we’ve also all heard the other arguments – you'll get sick, it's bad for your hair, it'll dehydrate  your skin. So what's the truth?  

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If i sleep with wet hair will it cause breakage?

Put bluntly, yes. Waterlogged hair is more prone to breakage. That’s because, when wet, the cuticle (the outer layer of hair) opens and swells and makes the hair strand stretchier and weaker. This, in turn, puts pressure on the delicate proteins keeping hair intact .

‘Hair can absorb up to 30% of its own weight in water,’ explains Adam Reed, GHD global ambassador. ‘Natural drying takes time. The longer it stays wet, the more the cortex swells and cracks, permanently damaging hair.’ 

Even a silk pillowcase or the best pillows for sleep can't prevent that.

While moving around while you sleep is likely to make hair stretch in ways that will cause it to break more easily, wearing your soggy strands up in a tight bun is even worse. More pressure is applied to the scalp when you're lying down which, in turn, pulls on the hair follicles and could be the reason more hair is clogging up your plughole.

It may be icky but there’s something else to consider here, too. Wet hair, coupled with a damp pillow, can create the perfect moist, warm environment for the yeast that causes dandruff to flourish. 

What about my skin?

Consider this – the reason dermatologists warn against using a face mist comprising simply of water is that you’re likely to get the opposite effect you were hoping for. ‘If there are no humectants in your face mist, your skin can’t hold onto the moisture,’ says Noella Gabriel, co-founder of Elemis. ‘The water simply evaporates off the surface of your face and dehydrates your skin.’ 

Now think about what happens when your waterlogged hair gets trapped between your pillow and your face. As the water in your hair evaporates, it can also suck some of the moisture from your skin.

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Will wet hair make you sick?

Okay, this may be the ONE time your mom was wrong. The idea that wet hair can make you feel chilly and give you a cold doesn't actually stack up when you consider the science. Colds are caused by viruses and bodily fluids, like when someone sick sneezes or coughs. So your wet hair is perfectly safe on that front!