INS and obesity due to melanocortin 4 receptor deficiency: Key search terms included: “Magnesium” OR “Serum Magnesium” OR “Magnesium Deficiency” AND “Insulin Resistance” OR “HOMA-IR” OR “Insulin Sensitivity” AND “Overweight” OR “Obese” OR “Obesity” AND “Children” OR “Pediatric” OR “Adolescents”.