Yes it is very much true. I will vouch for that.

Anxiety can also have an infleunce. The hair takes a few months to react because it is made a certain times before it makes its way out of the skin. That is what a hairdresser told me after seeing 'suspicious holes' in my hair at certain places, which is not very common at the age of 19.... At the same time, I was losing so much hair that it cancelled the slow growth of those remaining, which means over time there was always less, yet longer hair which meant my haircut would stay practically the same during several months.

Hair has however grown back sicne then, roughly at its pre-depression rates.