[23] Classes II (35.0–39.9 kg/m2) and III (≥40.0 kg/m2) obesity were combined into a single category (defined as ≥35.0 kg/m2) as the number of participants with higher levels of obesity were small, and this BMI threshold was reported to be associated with substantial iron disturbances in our recent systematic review. [5] Serum iron (p = 0.029), transferrin saturation (p = 0.042), ferritin (p = 0.021) and CRP (p<0.001) were significantly different between BMI categories, with CRP showing a significant increment between categories two and three (p<0.001) in the post hoc analysis (Table 4). Here, TF is linked to obesity due to melanocortin 4 receptor deficiency.