We summarize the simple fact that, on the one hand, the long chain C16–C18 FAs (LCFAs) are the most efficient stimulants of the insulin release in pancreatic β-cells [1,2], whereas, on the other hand, elevated LCFA concentrations in obesity via elevated oxidative stress and low-grade inflammation result in impaired insulin secretion and may lead to the disease progression of fully developed type 2 diabetes [3]. Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.