GHRL and major depressive disorder: These mechanisms are associated with mental health (e.g., depression, binge eating disorder, emotional eating, grazing and sweet cravings), maladaptive lifestyle behaviours (e.g., adherence to exercise and/or dietary recommendation), inadequate follow-up support, hormonal/metabolic imbalance (e.g., increased ghrelin levels) and anatomical/surgical factors (e.g., initial sleeve size, sleeve dilatation and amount of gastrointestinal track bypassed) [29,30,31].