In this episode of humanOS Radio, Dan speaks with John Newman. Dr. Newman is a geriatrician (a physician who specializes in the care of older people) at UCSF, as well as a professor at the Buck Institute for Research on Aging. He is chief investigator at the Newman Lab, where he is exploring ways to harness metabolic signals to promote health and resilience, particularly in older adults. Dr. Newman’s research focuses predominantly on ketone bodies - molecules produced in the liver when glucose is scarce, either due to restricted intake or prolonged physical activity. So we tend to think of them primarily as an alternative source of fuel, particularly in the context of a low carb diet. However, they are also intriguing with respect to aging, because of how they function as molecular signals, and how they influence gene expression.