INS and obesity due to melanocortin 4 receptor deficiency: An increased F/B ratio is commonly linked to obesity or metabolic disorders, potentially due to enhanced caloric extraction from food, fat deposition, lipogenesis, or impaired insulin sensitivity (Gibiino et al., 2018; Grigor’eva, 2020; Stojanov et al., 2020; Vaiserman et al., 2020).