INS and obesity due to melanocortin 4 receptor deficiency: According the carbohydrate-insulin model of obesity (CIM) [1, 2], the high insulin-to-glucagon ratio on a high-glycemic load diet shifts substrate partitioning from lean tissue to adipose, lowers the concentration of metabolic fuels in the blood in the late postprandial period, increases hunger and lowers energy expenditure – biological responses that would tend to promote weight gain.