Flores-Quijano et al. [15] also reported higher ID in obesity at <14 GW (defined by unadjusted ferritin <12 μg/mL: 3.8% in normal weight,7.5% in obesity; and defined by sTfR >2.11 mg/L, 1.9% in normal weight,7.5% in obesity). Here, TFRC is linked to obesity due to melanocortin 4 receptor deficiency.