NAMPT and obesity due to melanocortin 4 receptor deficiency: These findings demonstrate that obesity effectively develops in rats subjected to a cafeteria diet, as evidenced by increases in body weight, BMI, Lee Index, serum glucose, triglycerides, total cholesterol, LDL, and VLDL cholesterol levels, decreases in HDL cholesterol, elevated plasma asprosin and visfatin levels, reductions in liver β‐catenin and p38 MAPK protein levels, and histopathological changes in liver tissue.