#411 ‒ AMA #90: Strong convictions, loosely held: how Peter's views on fasting, keto, metformin, rapamycin, whole-body MRI, and exercise have changed

Hey, everyone. Welcome to a sneak peek ask me anything or AMA episode of the drive podcast. I'm your host, Peter Attia. At the end of this short episode, I'll explain how you can access the AMA episodes in full along with a ton of other membership benefits we've created. Or you can learn more now by going to peteratiamd.com forward slash subscribe. So without further delay, here's today's sneak peek of the Ask Me Anything episode. Welcome to Ask Me Anything episode number 90. In today's AMA, we're reflecting back on the first 400 episodes of The Drive with another episode of the, strong convictions loosely held theme. So what do we do with this? Well, we walk through some of the biggest positions I've taken across the eight plus years of this podcast, but then we revisit them by basically asking, where have the data taken us? What's changed, if anything? And as a result of that, of course, where where am I today? In this episode, we're going to talk about my evolving views on ketogenic diets, extended fasting as a longevity intervention, and the Doctor TRCR framework. Why I stopped taking metformin for longevity and my shifting position on rapamycin, whole body MRI and liquid biopsies for cancer screening, including why I think whole body MRI data quality has actually gotten worse over time and not better, how my approach to cardiorespiratory training and the eightytwenty zone two framework has changed, especially for people with limited training time, and why I stepped away from heavy barbell squats and deadlifts, and how to think about risk management in strength training. If you're a subscriber and want to watch the full video of this podcast, you can find it on the show notes page. If you're not a subscriber, you can watch a sneak peek of the video on our YouTube page. Without further delight, I hope you enjoy our celebration of 400 episodes together with AMA number 90. Peter, welcome to another podcast. How are doing? Very good. Thank you. You? Doing good. Doing good. So today, we are celebrating 400 episodes, about eight years. So we recently crossed this, and usually what we do is every now and then we'll look back at kind of a reflection episode. In the past, we've always referred to them as strong convictions loosely held. And so I think as we start and before we get into specific topics, do you kinda wanna remind people about what that term means to you, where you heard about it, and why you think it's so important? Yeah. It's a term that I first heard from a friend who ran a hedge fund, and obviously this was through the lens of his investment thesis, which was that obviously needed strong convictions, but because you're putting real capital behind a thesis. But those convictions had to be loosely held because the moment new information or contradictory information showed itself, you had to be willing …