How to convince husband?

my husband is 27 (IT Engg.), he never listen to me for exercise and to improve his eating habits, as breakfast he take tea and biscuits and some other stuff (i.e. fry and spicy) lunch chapatis and veg snacks tea and again all same and dinner chapatis and same, no fruits, no juice, and always with min. back pain and shoulder pain and some time wrist pain.. what to do plzz help..??