"Dieting" isn't what you want -- what you want is to change your eating habits permanently to something you enjoy but that's healthy and works to change how you're metabolizing what you're eating. Right now you're basically living on dairy. Maybe you're one of the two ethnic groups in the world who do well with dairy, maybe you're not, but living on just one food is not only boring but not the best way to be healthy long-term. The corn flakes aren't healthy either -- corn isn't the best thing to slow metabolism of food into sugar. You don't say what's in your salad, but I'm going to guess you're just not eating vegetables much, and they're the most important thing to eat for health. You don't say how long or vigorously you walk, but for a young person it doesn't sound like much exercise if your life is otherwise sedentary. You might benefit by doing some research on nutrition.