In the literature, obesity studies in experimental animals have reported that serum visfatin levels did not differ between groups (Pérez‐Echarri et al. 2009), whereas other studies have shown increased levels in the obesity group (Abdel‐Fadeil et al. 2019; Gao et al. 2014). This evidence concerns the gene NAMPT and obesity due to melanocortin 4 receptor deficiency.