I'm the odd one out of my girlfriends because I don't sleep with my hair tied up. It's uncomfy. End of. Heaps of people do do it, but some are scared in case it damages the hair. I checked in with Richard Kavanagh and co. to double check:
A) The main concern when tying your hair up, whether sleeping or staying awake is using a good quality hair elastic. If you use rubber, you can cause friction breakage and damage to the cuticle layer of the hair. The other thing to keep in mind is the possibility of tension alopecia or hair loss caused by pulling the hair too tight for too long. Other than that, there's no real problem with sleeping with your hair tied up; it can be a great shortcut to getting a bit of bend in the hair.
DO: Go to bed with a low, loose ponytail if you want to wake up knot-free — Maria Ardino
DON'T: Tie in the centre of your head. "Tying at the top of the head" is best, according to Kenneth Stoddart as this "doesn't disturb your sleep."
DO: Use it as a shortcut. "A bit of Satinwear 02 ($27) and a bun it up is a great way for soft waves," says Todd Arndt. Alternatively Richard recommends "going to bed with rags tied in your hair after spraying it with Style Connection Wool Shake 08 ($36.95)" for "a great curl with a beautiful texture."
Stockists: Redken (1300 650 170)