Depletion of leptin or insulin, or their receptors, generally results in increased food intake and obesity mediated by the brain, largely arising from lowered sensitivity to meal-generated satiety signals [19,21,22]; type 1 diabetes represents a pathological state of insulin depletion leading to weight loss due to severely impaired glucose utilization and reduced ability of adipocytes to store fat. The gene discussed is INS; the disease is obesity disorder.