For instance, hypothyroidism can increase body weight, and TSH is identified to be positively related with BMI and obesity, even within the normal range.43 Increasing TSH in overt and mild hypothyroidism is also found to be associated with unfavorable lipid concentrations (like hypercholesterolemia and decreased HDL levels),11,15 as well as blood pressure.44 Thyroid function also has an effect on the activity of cholesteryl ester transfer protein and hepatic lipase,45 which alters HDL metabolism. Here, CETP is linked to obesity due to melanocortin 4 receptor deficiency.