 Rapidly growing aging society augmented the risk of age-associated disorders, such as metabolic syndrome, type 2 diabetes, and cardiovascular disease. Dietary interventions that reduce daily energy intake, also known as caloric restriction CR, has been shown to be the most robust intervention to extend average and maximal lifespan in various experimental animals 1. In addition, CR diminishes the risk of multiple age-associated diseases, such as diabetes, cardiovascular disease, and some forms of cancer in rodents and primates rhesus monkeys 1; 2. Moreover, in obese humans, CR improves insulin sensitivity and reduces fasting glucose as well as the other components of metabolic syndrome 3. However, the exact underlying mechanism of CR has not been fully defined yet. 