It was related to age (t = 2.90; p = 0.004), being higher in patients with OSO obesity (57.71 ± 12.72 years) compared with levels among patients without OSO obesity (58.54 ± 13.24 vs. 50.93 ± 9.70 years, t = 3.55; p = 0.001), but no differences were observed with prothrombin, serum albumin or bilirubin, daily ethanol consumption, or years of addiction. Here, F2 is linked to obesity due to melanocortin 4 receptor deficiency.