INS and obesity due to melanocortin 4 receptor deficiency: However, under chronic nutrient overload as in obesity and metabolic syndrome, β‐cells secrete insulin in response to fatty acids, even at low glucose concentrations, contributing to elevated insulin secretion at nonstimulatory conditions that is characteristic of the obese prediabetic state (Nolan et al, 2006a; Merrins et al, 2022).