GHRL and obesity due to melanocortin 4 receptor deficiency: Plasma ghrelin levels depend on the short-term feeding status, rising before set meals and decreasing post-prandially (Cummings et al., 2001), as well as on the long-term energy balance, being lower in individuals with obesity and higher in energy deficit conditions, such as fasting (Cummings et al., 2002, Müller et al., 2015, Tschöp et al., 2001b).