INS and obesity due to melanocortin 4 receptor deficiency: Metformin, a commonly used drug that was shown to enhance insulin sensitivity and regulate blood sugar, is routinely used for the clinical treatment of obesity in women with PCOS.5 Additionally, as indicated by the Consensus of Medical Nutrition Treatment Experts on Overweight/Obesity in China, calorie-restricted energy-balanced diets have a positive impact on reducing weight in the obese population.6