The Peter Attia Drive - #84 - AMA #10： Low testosterone, hypothyroidism, building muscle (and preserving it while fasting)

00:00:00.000 Hey everyone, welcome to the Peter Atiyah Drive. I'm your host, Peter Atiyah.

00:00:10.140 The drive is a result of my hunger for optimizing performance, health, longevity, critical thinking,

00:00:15.600 along with a few other obsessions along the way. I've spent the last several years working with

00:00:19.840 some of the most successful top performing individuals in the world. And this podcast

00:00:23.620 is my attempt to synthesize what I've learned along the way to help you live a higher quality,

00:00:28.360 more fulfilling life. If you enjoy this podcast, you can find more information on today's episode

00:00:33.020 and other topics at peteratiyahmd.com.

00:00:41.440 Welcome to another edition of Ask Me Anything. Once again, I'm joined by my head of research

00:00:46.360 and my sidekick, Bob Kaplan. In this episode, we go really deep on about three things. There's no

00:00:53.760 speed round, but I think we make up for it by just the depth rather than the breadth.

00:00:58.320 So the first thing we talk about is testosterone replacement for men specifically, when it's

00:01:02.300 appropriate, related risks, benefits, the laboratory values one should and shouldn't care about.

00:01:07.540 So apologies that this one is a little more gender specific, but I think we've also already

00:01:12.240 covered this on the female side. So this is a very male-centric view of testosterone replacement

00:01:16.900 therapy. Second thing we jump into is thyroid replacement therapy. And just in general, thyroid hormones,

00:01:22.800 how they're produced, how the diagnosis of hypothyroidism is made in my opinion, how that

00:01:28.300 differs from maybe the standard way that people think about it and all sorts of other tangential

00:01:32.800 things around that. And then lastly, we talk about exercise and specifically we talk about exercise

00:01:37.760 and how it relates to nutrition with respect to building muscle. Now, to be completely clear,

00:01:42.500 and I disclose this fully in the episode, I don't consider myself an expert on muscle building,

00:01:47.640 bodybuilding, anything like that. You certainly wouldn't want me as your coach,

00:01:51.480 if you were training for such things. But at the general population level, which is where I

00:01:56.700 consider myself to be, I think I hopefully know enough to add value here. So anyway, we talk a lot

00:02:01.740 about the role of fasting, caloric restriction up and down, and muscle accumulation versus loss of

00:02:08.900 muscle. We also talk about autophagy, IGF, or insulin-like growth factor, and mTOR in the process.

00:02:15.120 So without further delay, here is AMA number 10. As a reminder, AMAs are for subscribers only. If

00:02:22.060 you're not a subscriber, you'll only be able to hear a preview of the AMA here. To become a subscriber

00:02:26.860 to have access to the members-only podcast feed, as well as other benefits such as detailed show

00:02:31.580 notes and member-only discount codes and the products I believe in, you can visit

00:02:35.100 peteratiyahmd.com forward slash subscribe. Hello, podcasters. Welcome to another Ask Me

00:02:44.520 Anything. I am joined by Peter Atiyah. This is Bob Kaplan. Peter, how are you doing?

00:02:51.100 I'm doing good, Bob. How are you?

00:02:52.640 Doing well. I thought we'd just jump right into it. Start off with some testosterone.

00:02:59.120 Wow. No foreplay. Go for it. 0.99

00:03:01.120 A lot of questions around testosterone. The essential question is, are you a fan of testosterone

00:03:09.120 supplementation as men age? If so, to what targets? Well, I mean, this is sort of a tough

00:03:16.420 question. It's very difficult to answer these questions in isolation because they're kind of

00:03:21.840 dependent on individual patients. Bear with me, I suppose, as I kind of give a soliloquy.

00:03:27.360 Regardless of what you're talking about manipulating in medicine, you should ask yourself

00:03:32.860 the question, what is the desired outcome? Am I manipulating this variable because I believe

00:03:38.860 it improves longevity? If so, does it improve lifespan? Does it improve healthspan? Both?

00:03:46.800 Neither? One more than the other? Testosterone, let's just now evaluate testosterone replacement

00:03:52.340 through that lens, which is, what do we believe it can help with? Well, I'm not really particularly

00:03:59.600 convinced that normalization of testosterone will improve lifespan. I could be wrong on this.

00:04:07.900 There are certainly associations that would suggest that that could be the case. For example,

00:04:13.140 low testosterone is not only associated with prostate cancer, but is associated with

00:04:17.800 more aggressive prostate cancer. By the way, I think that that's probably not saying that low

00:04:24.120 testosterone causes aggressive prostate cancer. I think it says that if you have prostate cancer in

00:04:31.000 a low androgen environment, it is likely to be more aggressive. We could probably spend an entire AMA

00:04:37.620 just debating the merits of testosterone replacement therapy, but in spending a lot of time in this

00:04:44.220 literature, I don't see a clear and obvious case that one will live longer because of it. And again,

00:04:52.560 living longer by definition means delay the onset of death, at least as it pertains to chronic disease.

00:05:00.900 So then I would sort of turn the table a little bit and say, well, is there evidence that it improves

00:05:06.000 healthspan? Well, healthspan again has three components. One of them is cognition. One of them is

00:05:13.320 physical exoskeleton. I still got to come up with a better name for this one, Bob. I hate saying

00:05:19.860 exoskeleton because it sounds, I don't know, like I'm talking about a grasshopper or something like

00:05:24.280 that. I always think of the Terminator. Okay. Even better. And then the third one is emotional

00:05:29.940 health, wellbeing, happiness, et cetera. Now, I think that testosterone can have a pretty significant

00:05:34.860 impact on two of those three. Which one's the odd man out? I'm not convinced that testosterone has an

00:05:40.380 impact on cognition. This has actually been studied once and we'll link to the study in the show notes.

00:05:45.580 It was studied quite recently, meaning in the last two years. The study had its limitations,

00:05:51.140 but it did not suggest that testosterone replacement therapy was improving cognition.

00:05:56.720 Now, I know that there are a lot of people out there, a lot of physicians out there who prescribe

00:06:00.160 TRT who would disagree with me on that and would say that empirically it appears to, maybe that's the

00:06:06.120 case. Maybe it's not. But as a selling point, I generally don't say to men, normalization of

00:06:12.220 your testosterone is going to improve your memory. Again, who knows what the placebo effect can mean

00:06:18.800 in this situation, but I generally by and large don't think that that effect is there. And if it

00:06:23.440 is there, I don't think it's that strong. Let's go to the area where there is absolutely no denying

00:06:27.880 the benefits of testosterone replacement therapy, which is the improvement of and or maintenance of

00:06:33.100 lean muscle mass, strength, conditioning, recovery from exercise, all of these things.

00:06:39.640 They all fit into this bucket of how does your physical body work? And there is no doubt that

00:06:45.400 testosterone improves those things. The magnitude that those things are improved, however, is not

00:06:51.440 obvious and is not entirely predicted by the number. So let's come back to that, Bob, if you can remind

00:06:59.460 me, because I want to really go into that. But just for the sake of completeness, let's turn our

00:07:03.800 attention to the last piece of health span, which is sort of happiness and emotional health.

00:07:07.880 Can testosterone improve those things? I'm a bit embarrassed to say, I don't know how rigorously

00:07:13.000 this has been studied, but the effects would be difficult to miss if you've ever treated patients

00:07:20.080 with low testosterone who then respond favorably, which is to say, you know, mood can get better.

00:07:26.300 Libido tends to get better. And maybe those two things alone are worth the price, you know,

00:07:32.820 worth any risks that are going to be associated with testosterone because someone whose libido

00:07:38.760 is shot, who now all of a sudden has, you know, desire to have sex again and intimate and be all

00:07:44.660 those things that alone could be a benefit to a person's relationship and therefore to a person's

00:07:49.220 life. So in summary, what am I saying? There's four things we think about, right? Living longer,

00:07:54.840 improving cognition, improving physical body, improving emotional health. I think two of

00:08:00.140 those three probably are impacted positively by testosterone. I think two of those three

00:08:05.140 are probably less so. And yes, there are lots of ways that having more muscle mass can also delay

00:08:11.320 death. So notice I said chronic death when I was talking about death, but of course it might be the

00:08:17.300 case that testosterone replacement therapy can improve muscle mass and functional strength that can

00:08:22.320 later in life prevent accidental death, which is probably the fourth leading cause of death when

00:08:27.980 somebody is old enough. Okay. I said way more about that than I wanted to, and I have not answered the

00:08:33.420 question yet, but do you, Bob, have any questions about everything I just said, or can I now go to the

00:08:37.920 next part of this? No, that sounded good. I know that we looked into testosterone and did some research

00:08:44.340 on it. And I remember seeing the, the endocrine society, their recommendations for TRT were for

00:08:50.700 symptomatic men with low T and they had the following purposes, which sounds like you pretty 0.95

00:08:55.760 much nailed them all. Improve sexual function, improve sense of wellbeing, improve muscle mass

00:09:01.100 and strength and increase bone mineral density.

00:09:03.960 You can find all of this information and more at peteratiamd.com forward slash podcast. There you'll

00:09:12.140 find the show notes, readings, and links related to this episode. You can also find my blog at

00:09:17.560 peteratiamd.com. Maybe the simplest thing to do is to sign up for my subjectively non-lame once a week

00:09:23.300 email, where I'll update you on what I've been up to, the most interesting papers I've read and all

00:09:27.920 things related to longevity, science, performance, sleep, et cetera. On social, you can find me on

00:09:33.380 Twitter, Instagram, and Facebook all with the ID peteratiamd, but usually Twitter is the best way

00:09:38.920 to reach me to share your questions and comments. Now for the obligatory disclaimer, this podcast is

00:09:43.560 for general informational purposes only and does not constitute the practice of medicine, nursing,

00:09:48.340 or other professional healthcare services, including the giving of medical advice. And note,

00:09:53.680 no doctor patient relationship is formed. The use of this information and the materials linked to the

00:09:59.020 podcast is at the user's own risk. The content of this podcast is not intended to be

00:10:03.300 a substitute for professional medical advice, diagnoses, or treatment. Users should not

00:10:08.120 disregard or delay in obtaining medical advice for any medical condition they have and should seek

00:10:12.840 the assistance of their healthcare professionals for any such conditions. Lastly, and perhaps most

00:10:18.360 importantly, I take conflicts of interest very seriously. For all of my disclosures, the companies

00:10:23.160 I invest in and or advise, please visit peteratiamd.com forward slash about.

The Peter Attia Drive - December 16, 2019

#84 - AMA #10： Low testosterone, hypothyroidism, building muscle (and preserving it while fasting)

Episode Stats

Summary

Transcript