Fasting also results in autophagy. There are several versions of IF [intermittent fasting]. Some restrict eating to eight to twelve hours per day. Others allow one meal a day. And others restrict nighttime eating. We have evidence that IF improves mood and cognition, and protects neurons from damage in animal models of epilepsy and Alzheimer’s disease. One group of researchers set out to understand how and why. You’ll never guess what they found—it’s mitochondria! Christopher M. Palmer, M.D.