Why do i get sore breasts before period?

I am worrisome about the sore breast which I get before my periods, it is painful and if it gets touched anyhow it begins to pain terribly. Am I taking the wrong food? If yes please tell me about the diet I should take during and before periods so that it may not cause soreness of breast. I am not sexually active, can this be another reason for my sore breast, please help and recommend some solution for sore breast.