We all know that air drying our hair is the healthiest thing to do to avoid damage from heat tools as well as colour fade, right? Well, according to experts, that’s not necessarily the case. It turns out, leaving your hair to dry naturally could actually be causing more harm than good.
As someone who washes their hair in the evening, this often means I’ll go to bed when it’s still a little damp and by morning, I’m good to go. I’ve always thought this was a genius time-saving hack as well as the best thing for my hair. However, leaving hair wet for extended periods of time or sleeping on damp hair could be causing something known as hygral fatigue.
“Keeping your hair wet for long periods of time (for example, overnight or air drying on a regular basis) can cause hygral fatigue, which is damage to the hair from excessive swelling,” explains trichologist Stephanie Sey on behalf of Nizoral.
“When hair is wet the hydrogen bonds are broken, temporarily, and by repeating the process of leaving your hair damp for hours on end is likely to damage the cuticle of the hairs and its outer layers, over-exposing the cortex,” Stephanie continues. In other words, the longer that hair is wet, the longer it’s swollen and the more pressure is put on the proteins and cortex keeping the hair intact.
UK Hair Expert and dermatologist Dr Sharon Wong agrees: “The hair has an outer protective cuticle layer formed of overlapping keratin protein layers like tiles on a roof. When these ‘keratin tiles’ are laying flat and tightly overlapped this creates a highly protective layer.” However, Dr Wong goes on to explain that when hair is wet, it is at its most “elastic state” and therefore vulnerable to things like friction.