Although many studies show strong correlations of serum RBP4 levels with the severity of insulin resistance and obesity and with certain components of MetS, including hypertension [12], dyslipidemia [12,13], waist/hip ratio [13], cardiovascular disease [14,15], and intra-abdominal fat mass [16], others do not demonstrate these correlations [17-19]. This evidence concerns the gene RBP4 and metabolic syndrome.