David is a Professor at Harvard Medical school, has founded or co-founded around 15 companies, his new book Lifespan: Why we age and why we don't have to, has just come out and is already a best seller. David is a high-profile scientist that is famous for his discoveries of the effects of resveratrol and its effects of Sirtuins and is now one of the top go-to people for all things anti-aging, with specific focus on NAD precursors, nicotinamide riboside or NMN. He is famous for taking these supplements himself and talks about this openly, although he doesn’t make any recommendations to others.