1. LEARN HOW WEIGHT LOSS WORKS
If you're an overweight young adult, you probably eat too much. By "too much," we mean more than you need. Your body needs a certain amount of calories to keep itself going, and if you eat more than that amount, you will gain weight. If you consume fewer calories than you expend, you will lose weight. It's that simple, and you must not allow charlatans and mountebanks to persuade you otherwise. Unless you have some sort of illness, this method will work for you. So read what we have to say, discuss it with your doctor, and follow it if he or she approves.The equation described above is complicated by the fact that your body doesn't like you to eat less than it needs; it will think you are starving. If you go on a severely limited diet, your body will do a bunch of irritating things, such as: giving you hunger pangs, making you feel tired and sluggish, drawing the energy it needs from your muscle tissue as well as your fat, etc. Therefore, you shouldn't try to lose weight by dieting alone.
You have to exercise in addition to eating less, so that your body knows that you are still doing just fine and is forced to maintain your lean body mass and live off your fat. If you eat fewer calories than your body needs, but don't go under your requirements by much, and exercise enough that your body keeps going and burns even more fat to do so, you will lose weight. And all the unpleasant nicknames that go with being a tubbo.
A pound of fat represents approximately 3500 calories of stored energy. In order to lose a pound of fat, you have to use 3500 more calories than you consume. It's best not to do this over the course of a day; you'd probably hurt yourself, and your body (knowing it, the uncooperative creature) would probably have some extreme reaction which did not involve you losing any actual weight. It's better to spread this out over a week, so that you aim to exceed your caloric requirements by 3500 to 7000 calories per week, resulting in weight loss of one to two pounds per week. It's not healthy to try to lose more than two pounds in a week, and if you do attempt to do so you're unlikely to be successful.
Let's say you want to lose two pounds per week. To do so, you need to figure out how many calories a person of your age, sex, and weight usually needs in a day (see Eat Less), subtract 500 from that amount, and follow a diet that provides you with that many calories. For example, if you would ordinarily need 3000 calories in a day, you would follow a 2500 calorie per day diet. Then you figure out how much exercise a person of your weight would need to do to burn 500 calories per day (see Exercise), and you get off your lazy ass and do it. The result is simple. 500 fewer calories consumed plus (minus, actually, but we don't want to confuse you) 500 more calories expended equals a 1000 calorie per day deficit, which, over the course of a week adds up to 7000 calories, or two pounds. Your mileage may vary, but there's no getting around it. If your body is consuming fewer calories than it's expending, something's got to go (see God, "The First Law of Thermodynamics").
That's how it works. Now you just have to learn how to eat less (see Eat Less) and exercise (see Exercise) and you will lose yourself some weight. We'll even tell you how to keep it off (see Keep the Weight Off.)
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