In this “Ask Me Anything” (AMA) episode, Peter explains some observations he’s noticed since switching to a 3-day fasting cycle from the longer fasts, the various things he’s measuring, and some helpful tips for getting through a prolonged fast. He also discusses the role of exogenous ketones in fasting and ketogenic diets as well as their impact on autophagy, specifically. Finally, Peter provides some practical advice for those looking to fit exercise for longevity into their busy life. Once again, Bob Kaplan, Peter's head of research, will be asking the questions. If you’re not a subscriber and listening on a podcast player, you’ll only be able to hear a preview of the AMA. If you’re a subscriber, you can now listen to this full episode on your private RSS feed or on our website at the AMA #13 show notes page. If you are not a subscriber, you'll be able to listen to a sneak peak of this episode. We discuss: Peter’s observations since switching from a 7-day to a 3-day fasting regimen [1:25]; Ketone measuring devices—blood and breath [7:40]; Can zero-calorie sweeteners affect ketone production? [10:40]; Will there be a continuous insulin monitor anytime soon? [11:55]; Exogenous ketones—Role in fasting and ketogenic diets and their effect on insulin, blood glucose, and autophagy [14:10]; 5 tips to help you get through a multi-day fast [25:55]; Relationship between BHB levels, glucose levels, and autophagy—Are high levels of ketones enough to produce autophagy? [34:10]; Why is measuring blood insulin so much harder than blood glucose? [36:55]; Advice and resources for people wanting to stay up to date on developments related to health and longevity (and how to quickly sift through all the bad science) [40:10]; Advice for those looking to fit exercise for longevity into their busy life [51:10]; and More. Learn more: https://peterattiamd.com/ Show notes page for this episode: https://peterattiamd.com/ama13 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.