Phentermine will damage your heart. Get rid of it. Join a structured weight management programme like Lighter Life, Weight Watchers, Rosemary Connelly. Go back to basics and learn what a healthy diet is. See a dietician and let her help you plan a fat and calorie restricted diet. Try Orlistat. At size 30, you'll probably not be able to do the amount and type of exercise that can reduce weight, so getting the diet right is key.