'The types and quality of food you eat influences more than how much you weigh. Food has an effect on your metabolism, insulin production, leptin release and a myriad of other hormonal and chemical balances.
Scientists are also examining the way fasting affects cellular and mitochondrial function, and longevity.
They’ve found the cells in your body react to fasting in much the same way as they do to exercise. In other words, when placed under stress — be it exercise or fasting–the reaction creates changes at the cellular level that helps extend your lifespan.'