Please don't go on any diets without going to have a word with your doctor. Your body is still developing, you need to be very careful that you get the right balance in your diet. You might find that in 6 months time you have a completely different body shape. Your doctor will look at all the factors that influence your weight, including your build, muscle to fat ratio, metabolism etc etc and advise you whether there is really any need to lose weight. If you do need to drop a few pounds, at your age it should be posssible to do this by making minor alterations to your diet and maybe getting more exercise. Above all though, remember that you are you, not your friends, not the people in the magazines, and you are fabulous just as you are!