It seems that when i am a diet, my hair starts losing! what's going on?

Nutrients: It sounds as if you are not getting the proper nutrients for hair growth when dieting. It also depends what you eat when youre on a "Diet" One piece of cheesecake all day- can be considered by some to be on a diet- I doubt it has all the vitamins, minerals and nutrients you need. I would recommend- fruits, vegetables, lean meats in portion control, legumes, whole grains to round out the diet.