INS and obesity due to melanocortin 4 receptor deficiency: As recently discussed, the tendency of some GM profiles to represent more the altered metabolic phenotype of obesity (such as cluster C2 in our study) could however be related not so much to the consumption of unhealthy foods as to the absence of Ruminococcaceae and Lachnospiraceae families, which are commonly related to beneficial effects on insulin and glucose homeostasis [69, 70].