This episode was a blast. It was a tropical exploration of biology, life extension, and all good things. This included a lot of Carmenere wine and good old-fashioned ball busting. I was joined by: Peter Attia, MD (@peterattiamd), who rejoins the show (catch his last appearance here). He is a former ultra-endurance athlete (e.g., swimming 25-mile races), compulsive self-experimenter, and one of the most fascinating human beings I know. He is one of my go-to doctors for anything performance- or longevity-related. Peter earned his MD from Stanford University and holds a BSc in mechanical engineering and applied mathematics from Queen's University in Kingston, Ontario. He did his residency in general surgery at the Johns Hopkins Hospital, and conducted research at the National Cancer Institute under Dr. Steven Rosenberg, where Peter focused on the role of regulatory T cells in cancer regression and other immune-based therapies for cancer. David M. Sabatini, M.D., Ph.D. (@DMSabatini) of MIT's Whitehead Institute for Biomedical Research. David is on a short list for the Nobel Prize for his work in elucidating the role of rapamycin and mTOR. Navdeep S. Chandel, Ph.D., the David W. Cugell Professor of Medicine and Cell Biology at the Feinberg School of Medicine, Northwestern University. Nav established his lab there to further the understanding of how mitochondria work as signaling organelles to regulate physiology and pathology. He is also the author of Navigating Metabolism. Perhaps you've heard of people in Silicon Valley taking metformin, rapamycin, and supplements for longevity. In this conversation, we dig into the real science, what current evidence supports (or doesn't), and other important matters like how to staple properly, which fonts reasonable people use, and why Borat is a genius. Enjoy! Show notes and links for this episode can be found at www.fourhourworkweek.com/podcast. This podcast is brought to you by 99Designs, the world's largest marketplace of graphic designers. I have used them for years to create some amazing designs. When your business needs a logo, website design, business card, or anything you can imagine, check out 99Designs. I used them to rapid prototype the cover for The 4-Hour Body, and I've also had them help with display advertising and illustrations. If you want a more personalized approach, I recommend their 1-on-1 service. You get original designs from designers around the world. The best part? You provide your feedback, and then you end up with a product that you're happy with or your money back. Click this link and get a free $99 upgrade. Give it a test run. This podcast is also brought to you by Four Sigmatic. I reached out to these Finnish entrepreneurs after a very talented acrobat introduced me to one of their products, which blew my mind (in the best way possible). It is mushroom coffee featuring chaga. It tastes like coffee, but there are only 40 milligrams of caffeine, so it has less than half of what you would find in a regular cup of coffee. I do not get any jitters, acid reflux, or any type of stomach burn. It put me on fire for an entire day, and I only had half of the packet. People are always asking me what I use for cognitive enhancement -- right now, this is the answer. You can try it right now by going to foursigmatic.com/tim and using the code Tim to get 20 percent off your first order. If you are in the experimental mindset, I do not think you'll be disappointed.