Ghrelin is a 28-amino acid peptide mainly secreted by the stomach. To better understand the role of ghrelin signalling, this book first explores the regulation of age-associated adipose tissue inflammation. Following this, the authors discuss the influence of different variables on the response of short-term appetite regulation induced by exercise. External factors such as temperature and environment exert effects on hormonal responses, including hunger sensation and energy intake. The effects of gender differences and aging on psychological stress-dependent eating disorders are assessed, and the involvement of endogenous ghrelin, the serotonin 2c receptor and the estrogen alpha receptor is discussed. The penultimate chapter reviews the relationship between sleep and eating behavior, focusing in the influences of circadian changes on appetite related responses such as plasma concentration of ghrelin. The concluding study highlights the ghrelin system as a promising candidate for cardiovascular drug discovery, a new therapeutic approach for the treatment of endothelial impairment, and a possible contribution to the prevention of atherosclerosis.