In a retrospective way we studied the relationships between the energy expenditure of patients with obesity, likely characterised by a systemic, low-grade inflammatory process and some parameters of immune response, mediated by spleen, to try to explain the gap between HGF, increased in NAFLD patients and an early stage of cardiovascular disease, i.e., atherosclerosis. Here, HGF is linked to obesity due to melanocortin 4 receptor deficiency.