In contrast, SIRT1 deficiency leads to the decrease in the secretion of thyroid hormone 12, estrogen 13, testosterone14, and pituitary hormone 15, causing disorders of endocrine and metabolic system, thereby developing into obesity 16, diabetes 17, hyperuricemia 18, hyperlipidemia 19, hypertension 20. This evidence concerns the gene SIRT1 and obesity due to melanocortin 4 receptor deficiency.