Glamour is a look, not a size. You don't have to be thin to be attractive. Diets are not sexy. If you want to be more attrcative, take care of your body and your appearnace. Feeling healthy makes you look your best.
Diets can turn into eating disorders.
The obsession to be thin can lead to anorexia, bulimia, binging, and compulsive exercise. Diets can make you afraid of food. Food nourishes and conforts us, and gives us pleasure. Dieting can make food seem like your enemy, and can deprive you of all the positive things about food. Diets can rob you of energy.