Hairproblems

I fear that is a side effect of my strict eating, I lost a lot of hair after the first year 2009 and I haven´t quite recovered from that.
Has anyone else the same problems? My doctors don´t take it serious, they think it is an age thing, hormons and so on...I am 44, can´t believe that this is the matter.
I started taking extra vitamins and minerals from the health store and extra Vitamin D.
Does anyone have other suggestions? I want my long hair back!!!