Well above one's normal weight. A person has traditionally been considered to be obese if they are more than 20% over their ideal weight. That ideal weight must take into account the person's height, age, sex, and build. Obesity is often multi-factorial, based on both genetic and behavioral factors. Accordingly, treatment of obesity usually requires more than just dietary changes. Exercise, counseling and support, and sometimes medication can supplement diet to help patients conquer weight problems. Extreme diets, on the other hand, can actually contribute to increased obesity.