Participants will include: Group A: normal weight, healthy volunteers (n=24: BMI: 18.5-24.9 kg/m2) Group B: patients with anorexia nervosa (DSMIV criteria and BMI: <16 kg/m2) B1: anorexia restricting type (n=12-20 over 2 years) and B2: anorexia bulimia type (n=20 over 2 years) Group C: patients with morbid obesity (BMI: 30-40 kg/m2) C1: obese (n=20 over 2 years) and C2: obese with DM type II (n=20 over 2 years).