In this episode, David Sinclair, Ph.D., a Professor in the Department of Genetics at Harvard Medical School and co-Director of the Paul F. Glenn Center for the Biological Mechanisms of Aging, returns to the podcast to discuss the content of his new book, Lifespan: Why We Age - and Why We Don’t Have To. This conversation focuses on the biological mechanisms involved in what David terms the Information Theory of Aging which provides insights into the “clock” that determines our aging and to what degree it can be manipulated. Our discussion on aging of course leads us into interconnected topics of epigenetics, sirtuins, cellular senescence, as well as what compounds David is personally taking for his own longevity. Additionally, we discuss the most up to date information related to NAD and longevity by looking at the potential benefits (if any) of supplemental agents (NAD precursors, NR, NMR, etc.) that pose a promise of increasing NAD. We discuss: SIR genes and cellular identity [8:45]; Sirtuins regulate gene expression [14:30]; DNA is methylated at the deepest layer of the epigenome [17:45]; Methylation pattern and determining cellular age [20:15]; Cellular reprogramming [33:45]; Yamanaka factors to push cells "back in time”  [41:00]; Human cellular reprogramming viability [57:00]; Measuring the rate of aging [1:02:45]; Cellular reprogramming for longevity [1:14:45]; Compounds David takes for his own longevity [1:29:15] NAD precursors (NR, NMN) and pterostilbene [1:40:00]; The current field of sirtuin activators [2:03:15]; David’s artistic work [2:05:15] and; More. Learn more: https://peterattiamd.com/ Show notes page for this episode:https://peterattiamd.com/davidsinclair2/ Subscribe to receive exclusive subscriber-only content: https://peterattiamd.com/subscribe/ Sign up to receive Peter's email newsletter: https://peterattiamd.com/newsletter/ Connect with Peter on Facebook | Twitter | Instagram.