Is there a way to get back my hair?

I have been laying in bed depressed for the past week ever since i found out that my hair line is receding. Im 25 and the past year i have been stressing and i lost a lot of weight due to lack of food (i was homeless at the time). I bought some biotin, a vitamin supplement that is supposed to strengthen my hair and maybe promote some growth. I want to look for shampoos and other products that really work and might extend the life of my hair. Does anyone know any products that can help me? I know this can also be hereditary but if i can fight it i will.