When your adrenal glands are not working well, it might affect your hair. We have all heard of people under extreme stress, such as a military general during a war, who's hair goes white in a few months. This has not been confirmed by medical evidence.
A very rare symptom of low adrenal function is for your hair to thin. Hopefully, when your cortisone levels increase, your hair should also. Sometimes thinning hair is simply genetic. About one third of all women eventually have thinning hair.
I wonder if when your adrenal gland function is low, then you are under a lot of stress, that your hair might be triggered to go white or thin sooner than it would normally. This is just a guess on my part.