Some researchers have claimed that the protective mechanism of HP is regarded as its negative impact on ghrelin and gastric acid production, and stomach ghrelin stimulates appetite, leading to obesity, which is a widely known risk factor in the development of GERD (Goll et al., 2007; Rubenstein et al., 2013). The gene discussed is GHRL; the disease is obesity due to melanocortin 4 receptor deficiency.