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

Peter Attia (0:10)

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 peterattiamd.com/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 am I today? So in this episode, we're going to talk about my evolving views on ketogenic diets, extended fasting as a longevity intervention, and the DR-TR-CR 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 80-20 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. And if you're not a subscriber, you can watch a sneak peek of the video on our YouTube page. So without further delay, I hope you enjoy our celebration of 400 episodes together with AMA number 90

SPEAKER_2 (2:16)

Peter, welcome to another podcast. How are you doing?

Peter Attia (2:18)

Very good. Thank you.

SPEAKER_2 (2:19)

You? Doing good. Doing good. So today, we're 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, before we get into specific topics, do you kind of want to remind people about what that term means to you, where you heard about it, and why you think it's so important?

Peter Attia (2:46)

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 the thesis. But those convictions had to be loosely held because the moment new information or contradictory information showed itself, you kind of had to be willing to check your ego at the door, say maybe I was wrong, and how do I need to change things? I always thought that that frankly was a great view of how to think about everything, where there's actual information at play, and obviously medicine and science are great examples of that.

I've been around many really great scientists, and one of the characteristics they all have in common is they're not married to a particular thesis being right. They're married to getting things as right as possible and reducing uncertainty by following the data wherever those data take them. So I think it's important that we are revisiting our assumptions. And as someone asked me once, if you were to write Outlive 10 years from now, do you think it would be the same book that you wrote three years ago? And I would say no. In fact, that would be concerning if it were the same book in 10 years as it was at the time it was written, because it would either suggest I'm too rigid in my thinking or science has made no progress. And I think both of those would be challenging. So yeah, that's loosely how we think about this episode.

SPEAKER_2 (4:17)

And Peter, when you're kind of looking at your opinions and how you're thinking about things and how they evolved, where does that traditionally come from? What are the triggers that are causing you to potentially change your opinion or how you look at things?

Peter Attia (4:31)

I think it's a combination of obviously things that change in the literature, but scientific progress is by its very nature somewhat glacial and episodic.

It doesn't just progress at the same rate.