Although it was proven in animal settings that the supplementation of EAA, rich in BCAA, increases the lifespan by protecting mitochondrial biogenesis and implementing mitochondria efficiency-related systems (i.e., endothelial nitric oxide synthase: eNOs, cytochrome c, reactive oxygen species: ROS, and antioxidant defense expression) [34,35], Fontana et al. claimed that branched-chain amino acid restriction is a possible promoter of health, a hypothesis based also on the preliminary observation that the plasma profiles of diabetes type 2 patients are characterized by high levels of BCAA [27]. Here, NOS3 is linked to type 2 diabetes mellitus.