Several experimental models show that NT mediates the development of fatty liver disease and obesity [6,7,8] while, in humans, large epidemiological studies demonstrate that higher circulating levels of pro-neurotensin (pro-NT), which is the stable NT precursor released in equimolar amount with NT, predict obesity, type 2 diabetes (T2D), and cardiovascular disease [9,10]. This evidence concerns the gene NTS and obesity due to melanocortin 4 receptor deficiency.