GHRL and obesity due to melanocortin 4 receptor deficiency: In conclusion, based on correlation analyses, our results distinctly revealed that both fasting AcG and UnG levels are markedly decreased in obesity with the proportion of active, acylated ghrelin increasing with increasing BMI giving point to a pharmacologic intervention in ghrelin acylation as a treatment of obesity despite decreased absolute AcG levels and /or increase in UnG in patients with high BMI.