The diet-induced obesity model most frequently used is the C57Bl6J mouse model (Fergusson et al., 2014) that may be highly responsive to overfeeding, due in part to the lack of the mitochondrial enzyme, nicotinamide nucleotide transhydrogenase (NNT), needed to effectively scavenge ROS (Fisher-Wellman and Neufer, 2012). This evidence concerns the gene NNT and obesity due to melanocortin 4 receptor deficiency.