We’ve Got Testosterone Completely Wrong | Dr Channa Jayasena

0:00Dr Karan: It seems around every corner we're being told we need more testosterone, like it'll cure literally any health problem we have. But how much of that is actually true? Dr Channa Jayasena is a specialist in reproductive health and he's here to discuss testosterone, the myths around it and the latest in the reproductive science. The wheels have come off. It's kind of like open season. There is debate about what is a low testosterone, but I think now people are going way beyond that and just thinking, well, why should I just have it anyway? Why do you need to have a low testosterone? I'm Dr. Karan, and in this podcast, I speak to the world's foremost experts in science and medicine to cut through the BS of modern health advice.

0:39Dr Karan: Thanks as always to Loam Science for sponsoring the show, the world's first invisible fiber blend with clinical trials. Dr. Chana Jayasena, welcome to the show. And I really feel that this is a hugely important topic because I'm seeing this everywhere now. There is a huge market around for optimizing testosterone. I mean, the London Underground is full of ads that may say things like feeling irritable, it might be low testosterone. And I wonder, are we really in a crisis of low testosterone or have we taken a very real disease like hypogonadism and expanded it into an explanation for almost every unpleasant feature about being a tired middle-aged man?

1:19Dr Karan: And, you know, of course, low testosterone can make you feel tired, but being tired doesn't mean that you have low testosterone. So in my opinion, anyway, we seem to have gone from treating testosterone deficiency to then selling testosterone optimization. And I wanted to get your thoughts on that. No, thank you. And thank you so much for having me on the show. I think not to be complex about it, but I think actually both of your options are to some extent, right. So we are objectively seeing this decline in male testosterone levels on average because we're living longer. And I think in the 1970s, men were often dying in their sort of 60s, 70s, whereas now we have an aging population and we know that testosterone declines as you get older.

2:06So I think there's a population phenomenon, also increasing awareness with the internet. But I think there's a second problem which you highlight, which is, I think, this kind of popularization of testosterone and using it for reasons that it was never meant for, almost as a lifestyle recreational drug where actually men are being, I think, manipulated into taking it when they don't need it. And if we look at some of the NHS data, and the NHS data shows that prescriptions for testosterone

2:39Dr Karan: in the UK specifically jumped 135 % between 2021 and 2024. Now, before I ask you the question, is this warranted? I guess maybe I should caveat that that 135 % rise isn't necessarily evidence of overtreatment. It could potentially mean that we were historically for years undertreating. But which would you say is more true that we are more aware of it and we are treating it appropriately now, the low testosterone and testosterone deficiency? Or is it because of the excellent marketing and branding of, you know, pop up direct to consumer clinics that maybe, you know, we're beginning to excessively over treat this?

3:21So I think if you look at the data, if it's particularly sort of capturing NHS and hospital data, I think it's more the fullness. So in other words, I think there has historically been a problem about men coming forwards with problems to do with sexual health. There's a big stigma, and I think there still is, but I think those walls are kind of coming down slowly, but surely. And I think that testosterone had some historical real concerns about its cardiovascular safety, and recent evidence has, to some extent, really sort of provided reassurance there. So I think there is genuine correction of historical under-prescribing in some ways, But I think the new phenomenon is coming in where I think we're seeing people who are, there are no guidelines that would suggest that they should be treated, who are in some quarters either buying it online or kind of getting it from clinics, often online, which really shouldn't be prescribing them.

4:23Dr Karan: I mean, so in your clinical practice, where do you see that line between correcting an actual deficiency and then a medication being used to enhance a normal hormonal level? Because right now I see, you know, to your point earlier and to my point, testosterone is being marketed online as a cure-all by a lot of companies, health influencers, biohackers, similar to what we're seeing in the menopause space as well, where, you know, menopausal hormonal therapy is being, having a similar packaging for, you know, women in that perimenopause, postmenopausal stage. What I'm seeing now that I didn't see, say, five or 10 years ago is men rocking up and they're doing this around the country within National Health Service hospitals and otherwise with plainly normal results or no evidence of appropriate testing to find out whether they actually had a low testosterone in the first place.

5:20So I think what's happening is that the wheels have come off. It's kind of like open season. So I think there is debate about what is a low testosterone and what those numbers are, et cetera. But I think now people are going way beyond that and just thinking, well, why should I just have it anyway? Why do you need to have a low testosterone? And if you look at social media and what's happening around us, you can kind of understand why they're thinking that.

5:50Dr Karan: Yeah, I guess also one of the weird knock-on effects of this hyper-optimization culture, especially with regards to testosterone, and one of the weirdest bits of testosterone culture is probably the obsession, not just with high testosterone, but specifically eliminating estrogen, when we know that some of testosterone, it is converted into estrogen, and one of its important effects is because some is converted to estrogen and estrogen is involved in critical functions for men as well as women as well. And I guess that this ties into this slightly exaggerated medical truth that testosterone is a masculinity molecule.

6:31Dr Karan: You know, obviously it's not, even women need testosterone as well. And it's a hormone with receptors in multiple tissues. And, you know, as we were saying before, the estrogen specifically, it's crucial for bone health in men contributes to sexual function, body composition. Do you think that this current culture and this obsession with testosterone is further undermining medical science? Yeah, I think you make some great, great points there. And I would, you know, I congratulate you on making the point about estrogen. And I think we tend to be very binary about testosterone men, estrogen women.

7:03And like you say, like if we didn't have estrogen receptors or estrogen actions as men, we'd have osteoporosis, but also we'd have no libido. So the way that testosterone acts on the brain to trigger interest in sex is through local conversion through an enzyme called aromasase to estrogen to have function. And so having too little estrogen as a man can be really, really bad. Rather than thinking as undermining medical science, I'm probably more optimistic. I think what happens in media and online forums is that these nuances are potentially lost. And I think people search for easy, intuitive one plus one equals two solutions.

7:47And as you'll know and I know, actually, if you dig a bit deeper into any field, the nuance is actually what actually makes things tick and is the difference between successful treatment and unsuccessful treatment. And so I really want to kind of extend almost to say, I don't mind this. And I just think that as a medical community, we need to do more to kind of reach out to sort of say, partner with us so that we can help you and tell you if something's going to help or not.

8:17Dr Karan: Yeah. And just to kind of pull that thread a bit more, someone's testosterone level may obviously be determined by genetics and various lifestyle factors as well. But actually, I guess when I'm looking at someone's testosterone result or when someone online is talking about their testosterone results, whether it's high or low or in the normal range, it goes beyond this facade of masculinity. And it's not just telling you about the health of your testicles, right? It is telling us about someone's general lifestyle behaviors, good, bad, any vices they may be having, their entire metabolic health.

8:52Dr Karan: And in the run up to this episode, I was just doing some research and I came across this large individual participant meta-analysis of over 25 ,000 men. And interestingly to note, probably things that we knew already, but that BMI and high BMI was one of the strongest correlates of low testosterone. And if you moved someone's BMI from what would be considered normal from 25.5 to 29.6, that was associated with a reduction in total testosterone. Diabetes was associated with a reduction in testosterone. And low vigorous physical activity was also associated with low testosterone. And these are things which seem like relatively easy levers for someone to have control over.

9:34You're quite right. And I think it's almost flipping that I think it's very intuitive for men to think I have a low testosterone. If I give myself testosterone, I solve my problems. But in fact, the opposite is true. I have a low testosterone almost certainly because my health status is reduced. So addressing that is the key. And it's almost like a VO2 max, isn't it? So if you have a low VO2 max and I'm trying to improve mine as someone who's just turned 50, the answer is not pumping myself full of gases, right? It's actually thinking, okay, what are the underlying causes and how can I train myself to make that difference?

10:14And getting that message out is so important.

10:16Dr Karan: Yeah, I feel often we chase the end outcome, but not the path it takes to get there. And you mentioned the point about VO2 max, that is a downstream consequence of good physical health and stamina. Same I've seen with, in the longevity space, especially grip strength. We have grip strength as a proxy of longevity, but it doesn't mean that, you know, doing grip exercises is going to make you live longer. Grip strength is higher because someone probably is doing more resistance training and has higher lean tissue mass, which is why they have higher grip strength. And sometimes we're chasing the wrong proxies, right?

10:52Dr Karan: Exactly. That's why these conversations are so useful for men to listen to. So hopefully, like, fill in the gaps, and also not to focus too much on an individual number. Because I see a lot of men saying, my testosterone was 10.7. And now it's crazy. It's 10.5. And I kind of want to say, look, I know, this may be breaking bad news to you. But look, our hormones are bouncing around all the time. It's like a dynamic world that we just take snapshots in time off. And actually, assays, the way we measure things vary as well. So that actually, I think our increased ability, our technology to measure data makes us almost imprisoned by it.

11:40But you and I probably are some of the few people to actually appreciate that actually the ways that you measure it are very fuzzy and that you shouldn't be spooked by individual measurements and actually focus on the fundamentals of the underlying reasons of how you can improve it. If your weight goes up slightly one day, it doesn't matter. You know it varies. It's the same thing with testosterone.

12:02Dr Karan: Now, as someone who's squarely in the front lines of the testosterone wars and the testosterone space, do you frequently come across men who have this nebulous fear that they aren't manly enough because they have a low testosterone? Yeah, and again, this is such a new phenomenon. And it's only in the last three or four years that I get men coming to me. And it's all about the story in my field. If someone comes to me and they say, I never felt I went through puberty properly, but objectively they have, they are in the normal range in terms of voice development, body hair development, etc. Or my muscles haven't developed properly.

12:48These are increasingly attributed to a worry that they haven't got the right reproductive system and testosterone driving things. This is more a philosophical question about us as men, about how we view ourselves and how I think we're increasingly within, you know, under the lens of media and social media attention and how image has changed. So I think testosterone has very much been focused on by some men who are really feeling the pressure of body image and are trying to see whether that could hold the answers that they wanted to know all their lives where clearly the answers lie elsewhere.

13:30Dr Karan: I do think, based on the back of what you said, there is a huge insidious, you know, underneath the tip of the iceberg, a male body image crisis, probably exacerbated by social media, where we see hundreds, if not thousands of ultra lean, shredded, jacked men on your feed every single day. And this starts to distort what reality actually is. And instead of seeing as a highlight reel and a curated library of, you know, just very genetically gifted individuals, maybe some taking testosterone, athletes, fitness professionals, and that then becoming the new norm. I think a man now who is in good shape, but who doesn't have a six pack and, you know, 22 inch biceps suddenly thinks that they are less than adequate because of that.

14:19Dr Karan: And we're seeing that even, you know, from Hollywood. If you've ever watched any of the Wolverine movies with Hugh Jackman or any movies with Hugh Jackman, you know, that's the new standard. And, you know, I don't want to point at individual people, but a lot of actors would use means of enhancement to get a certain physical physique for a movie that'd be paid millions of dollars for. So they, you know, may want to take a shortcut to get there in a few months. But then that's not the headline which makes the social media, right? We don't know what these people are doing to get a certain image.

14:50Dr Karan: And I think that taints what normal looks like. And even if you look at, you know, I took the example of Hugh Jackman. Hugh Jackman in the X-Men movies from the 2000s, and then you compare Hugh Jackman in the X-Men movies in 2020 and beyond. He's older, but even more jacked and shredded, which also I think is a nice corollary of the change in male body image that we've seen. It's no longer okay just to be lean and look in good shape, but it's got to be vascular, hugely jacked, ripped so you can even see someone's pancreas pumping away. Yeah, you're right. And actually, it's been starting earlier than that, even in the 20th century.

15:36There's a really nice research paper on the evolution of anabolic steroid use. And if you look at the Star Wars action figures, and if you see Luke Skywalker from the original 1977 movie, him as a kind of a really scrawny young teenager to the one from the early 2000s reboot, where he looks like He-Man. man that alone shows you how behind the background the image of what it is to be a man has fundamentally transformed and bears no resemblance to what it was and actually if you look at old pictures and portrait galleries and things you will see actually how things have turned on its head and actually over nutrition was seen as a way of mitigating risk from you know tb and malnutrition whereas now of course things are different and i think that um we at imperial college are trying to actually develop programs to address body image disorder and working with experts in clinical psychology because we think that yes the tip of the iceberg is that some of these men will be the ones who take on analibic steroids but then the step below we're seeing this part of the major male population, who's kind of almost tilting that way by thinking about enhancement, which they don't really think is anabolic steroid use, which may or may not accompany a prescription.

17:04Dr Karan: I want to talk about something that's quite post-it to me and about some medical conditions that I suffered from. I used to have high cholesterol and fatty liver disease, and that primarily stemmed from a severe lack of fibre in my diet. And on my quest for finding the perfect fiber supplement over the last few years that could help me add more fiber into my diet, I couldn't find one. That ticked all the boxes that I wanted and the high bar that I set for myself. So it built Loam Science. What I'm most proud of is not the product. I know that's great, but it's the fact that we've run two clinical trials on it, two randomized controlled trials, which is far more than the vast majority of supplements on the market will ever do.

17:39Dr Karan: And we've got even more coming because I'm a doctor first and foremost and a scientist, And I wanted to build something that I could actually stand behind with data and not just rely on good branding. So if you want to understand what's inside Loam Science and why, the science is all on the website and the link is in the show notes. Now, we often hear men saying, and you must get it all the time, that, you know, I must be having low testosterone because I'm tired. I'm struggling to lose weight. I have no motivation. Issues in the bedroom with their partner. Now, a lot of these are just generally vague symptoms.

18:12Dr Karan: And it seems to me that the more vague the symptom, the more dangerous it can become to then use that as a point of blame on hormones. And I guess the really important question is, what are the signs that you are truly deficient? So there are some, first of all, uncommon but highly suggestive features. So men who, at an extreme, haven't had their waist drop, haven't had proper hair development, or maybe have anemia or fractures from a young age. Those are really extreme gimmies that you don't often see. But for everyone else, it's really about sexual symptoms. So I think that anyone who has unexplained ED, erectile dysfunction, must be investigated.

19:00And that's the equivalent of a woman not having periods. And that is a fundamental aspect of male health that needs to be protected and men need to be vigilant for. Things like libido and early morning erections, so waking up with an erection as a reflex, are also really important. Some men will feel them and have them less relevant depending on whether they're in a relationship or not. So they're not always the most easy to elicit. But if you look at other symptoms, those are really quite nonspecific. They're supportive of diagnosis, but they're not really discriminatory.

19:41Dr Karan: One of those vague symptoms that I see plastered everywhere is fatigue. Fatigue, I think, for me, has become the testosterone marketing equivalent of inflammation that you see everywhere. It's vague enough that it will capture a wide net of people and allows companies to sell almost anything. Can you have testosterone levels that are technically normal, but you're still experiencing some symptoms? And then also, can someone have testosterone, you know, low testosterone without any obvious symptoms as well? Great question. So they're both correct. So we know that if you look at population studies from Europe and the United States, there are many men who have entirely normal levels of testosterone.

20:28And, you know, we all feel tired. We all feel low libido. We can all feel any symptom and it bears no resemblance to their testosterone level until your levels get really low. And conversely, you can be a young 18, 19-year-old guy, you know, top of physical condition, entirely normal sexual function, and have a very low testosterone. So this shows the challenge of using blood testing for diagnosing a condition in well people or trying to take highly symptomatic men and trying to diagnose testosterone deficiency unless they have a very low testosterone. So it's unfortunately not a condition that you can diagnose simply in isolation, but requires consideration of someone's where they're coming from, their symptoms, their life and their health.

21:25So I guess, you know, to that point, if you're healthy, you're happy, does it actually matter or do you even need to know your testosterone measurement?

21:36Dr Karan: And does it actually matter? Because if, you know, if you're asymptomatic for those reasons, and I'm wondering, because of this culture that's going on that's so pervasive, if you're happy and healthy, could then knowing your testosterone levels when there was no clinical indication to actually measure it, make you less healthy in the short and medium term? Because you're now turning a normal biological variable into a score that you're then trying to optimize, almost like everyone wearing sleep rings and tracking their sleep when they maybe never had problems with their sleep, and now they're getting obsession about their sleep data?

22:09I don't know what my testosterone is and I don't care because I feel healthy. And I think that's the advice we give for all men with, well, all people in general with tests, because tests are only defined as abnormal if you lie outside 95 % of the population. And we know that if you put yourself through a body scanner, you take a a testosterone test or any test there's a chance of causing harm which could be worry but also unnecessary treatment and the morbidity the the health that comes from those um and so i'm right with you on this one that the thing that should trigger investigation is starting with symptoms such as sexual symptoms and i want us to be in a in a world where men can come forward and get effectively investigated when they have them?

23:02Dr Karan: I've heard plastered everywhere online and on social media as well that testosterone, well, you've said it as well in this conversation, testosterone declines as men get older. That's obviously, you know, the objective truth based on the science and there's a gradual decline. However, sometimes, you know, there's a bit of hyperbole online when that age-related association between, you know, just growing older and declining testosterone, the size of that effect is frequently exaggerated. And the European male aging study found that I think there was 0.4 % total testosterone per year cross-sectionally was dropped and longitudinally 0.54%.

23:44Dr Karan: But if you take out age as one of the variables there, it seems actually the biggest levers in dunking your testosterone are the metabolic health factors, obesity, illness, other comorbidities seem to make probably a larger contribution than just age. So actually, I'm wondering, and question to you, should we be making the distinction less about getting older, lower testosterone, but more about unhealthy aging, lower testosterone more than healthy aging? You're quite right. And actually, we can see from the European Medi-Aging study that 70 plus year old guys can have brilliant testosterone if they actually maintain good health and are physically active and have managed to stay out of things that aren't under other controls such as cancer and the age is less relevant than how old they feel and how their body is so their biological age and i think that's a lesson for all of us um to aim for that rather than a number, rather than worrying about what their testosterone is.

24:54Dr Karan: And you yourself actually looked at new data from the Hebrew University Hadassah Brown School of Public Health and Community Medicine, the Israeli group. And that study obviously suggested, I think that's one of the most popular studies in this space, where it suggested that men's average testosterone levels halved in the last 50 years. And I think a lot of companies have probably profited off that single headline snapshot. Now, obviously, this represents a population trend. It doesn't mean that every single man's testosterone is falling. But how significant is that headline and what are the flaws with that headline and the data?

25:30Yeah, I think it comes back down to the issue of how healthy the population is that you're measuring. And we know that from the 1970s, men who would have been sampled and had testosterone measured would have been on average younger and healthier than they are now. So all that study has done is simply captured that phenomenon that people are living longer, but people are living to be less healthy on average. And as long as you understand that, then that's fine. I think the mistake is, and I think you've illustrated it beautifully, that men out there don't realize that detail. And actually, if you are not smoking, keeping fit and active, then those are the fundamentals that will prove resilience to problems with testosterone and problems with many other health problems.

26:25Dr Karan: Beyond things like obesity and smoking, as you mentioned, and physical activity, are there any other outside factors that people are concerned about with regards to lowering their testosterone? Well, we think that things such as cannabis exposure, because it actually has estrogenic properties, may be particularly bad. And for people who take very strong opioids, such as strong painkillers or obviously take it illicitly, that shuts down the hypothalamic signaling that's needed for activating the testes, and it causes absolute hypogonadism and infertility. So those are clearly particular groups where they almost all have testosterone deficiency.

27:12Dr Karan: Now, there are a lot of people who fearmonger about certain things. And often that one that, you know, goes into that bucket of fearmongering is pesticides. You know, obviously a lot of pesticide use, increasing pesticide use over the last few decades that has no doubt, you know, been associated in a similar sort of probably graph, whether it's coincidence or otherwise with declining fertility levels. Have you seen any research to suggest that there could be something of a causal link between some of these new environmental agents like pesticides and fertility, or is it purely coincidental association?

27:51So we know that some pesticides and other chemicals and plastics could have what we call endocrine disrupting properties. But there's been a big problem with trying to prove causality because you can't ethically expose people to these things. So you're just looking at association studies. Having said that, in the last five years, we're starting to get studies showing that if you try to correct statistically for what we call confounding factors, and the big one is social deprivation because people who live in polluted areas tend to be more deprived. High quality studies seem to suggest that male offspring born to mums in these polluted exposed conditions appear to have very subtle defects in their genital development, such as anogenital distance and more likelihood of having things like underscended testes.

28:53So I see it more of a modifier, almost like the weather, in that I don't think people are coming in in their droves having pesticide-induced or plastic-induced injuries. But I think there's little doubt that there's likely to be a modifying factor on everyone's reproductive health. The big question is how much and also what do we do about it?

29:18Dr Karan: Yeah, I guess all of that research on declining fertility, that's almost the experiment that we need to interpret the headline with. If men have become metabolically less healthy and we're exposed to more environmental agents which are having an impact negatively on testosterone, are we actually witnessing a testosterone crisis or is testosterone merely acting as a biomarker of a wider metabolic health crisis? Yeah, it's entirely plausible that the latter is true and that there are other things going on, particularly, as you say, environmental exposures, reducing testicular functions so that they're less resilient to these environmental insults such as obesity and diabetes.

30:06What I would say is that with the exception of refraining from, say, microwaving kind of disposable plastic kind of takeaway things and, you know, using dedicated high quality containers that don't contain sort of very soft plastics, then it's difficult to advise people what to do because pollution is around us all.

30:29Dr Karan: Now, if you simply inject testosterone and never investigate why it was low in the first place, which I imagine a lot of people are doing, could you potentially be silencing the alarm without actually checking the engine? I always like to play a thought game of, what if everyone in the population was treated? What would happen then? And I think you're absolutely right. You might have everyone saying, this is brilliant and having some potential stimulatory effect on their libido and how they feel. But at what cost? We know that testosterone doesn't make you live any longer if you take it. so actually if all the men who are interested in taking testosterone actually have as we know worse parameters of health whether that be obesity diabetes or even things like depression and stress then merely by taking what is essentially a distractor does not help them with their underlying health problems which will persist and obviously be detrimental to their health Yeah, I feel this is one of the strangest facts or paradoxes in endocrinology, where testosterone obviously is essential for making sperm, but then taking testosterone exogenously, you're injecting it in addition to what you have, that can potentially stop you making sperm.

31:55Dr Karan: And, you know, when a couple is struggling with, you know, fertility, experts and even the public are always looking at the women to find out what the problem is. And obviously a man can be involved in up to 50 % of infertility cases. How much as a role does the man play in infertility when it comes to testosterone, but also men that you've seen who are supplementing with testosterone and that specifically having a role to play in abnormal spermatogenesis and low sperm counts? So I think that's a great point. And I think that we haven't yet captured in published studies the impact. But I keep on telling my colleagues in the infertility world, watch out, because the more people in the population are on testosterone, then the more we will risk seeing couples with testosterone induced infertility, for want or a better word, which will, I think, become an, I'm starting to see it in my clinic.

32:54and it's just going to increase.

32:57Dr Karan: I mean, this is not a direct study based on what we've discussed on testosterone, but I came across an interesting piece of maybe adjacent research. It was an integrated analysis of over 1 ,500 men exposed to androgen-based male contraceptive regimens. And they found that actually the recovery to a sperm concentration of 20 million per mil occurred in approximately 67 % by six months, 90 % by 12 months, 96 % of men by 16 months. And then eventually all the men had returned to, you know, at least that normal sperm count by around 24 months in those trial populations. And I think, you know, it's worth noting that obviously these were controlled male contraceptive studies, you know, generally involving healthy men, not necessarily people who have taken TRT an anabolic steroid for years, but maybe that is some sort of proxy that can warn recovery, you know, that it can take months, if not years of recovery, if you're abusing steroids or taking it inappropriately.

34:00Yeah. And we're increasingly finding there's an interesting divergence so that if you particularly take what we would all call steroids, ROIDs, with very, very strong high doses, there's a concern that it could in some cases take most men will recover within 12 months but in some there's a possibility that it could take years what i would also say is that therapeutic testosterone if you take it because you need it we can be reassuring that there is no association with long-term fertility so i think the basic message connecting the dots is is the better the reason you have for taking it, the better it is in terms of being reassuring about fertility.

34:47But the less you need it, the more chance there is of it messing around in the long term with your reproductive system.

34:55Dr Karan: A lot of men who are taking testosterone aren't just taking that. They're often taking that in a cocktail with other potent things like growth hormones and now increasingly peptides do you think that can make matters worse oh boy i mean peptides is something the new kid on the block and the problem is is that i don't think anyone knows including the people who are taking it what they're taking and you can buy a white powder on ebay or wherever and it's we're looking into the evidence here at imperial college and there is almost no evidence underpinning these peptides role in health and often they're from cell lines or rats and certainly haven't been properly tested in humans.

35:41So there are multiple levels of risk associated with these things. So it's almost certainly going to be significantly detrimental to your health and magnify the risks if you take many different types of these compounds, particularly if they're from the dark, you know, from underground labs, because the purity cannot be vouched for. And also the, the testing, the evidence base is not there at all.

36:08Dr Karan: Now, in addition to a lot of promotion of peptides online by health influencers, there's also this entire world of, you know, naturally boost your testosterone advice and hacks online from, you know, taking cold showers to certain diets, to certain exercise routines, or grinding and eating, you know, organ meats. What actually affects testosterone in terms of from a natural way that, you know, someone can do on a daily basis, weekly basis that will move the needle? So this is where I think I'll disappoint many of the listeners in that there is no easy, quick fix for gaming your testosterone. Like doing a few press ups, pumping iron, none of these none of these kind of explosive things give you a boost in testosterone.

36:54What your test, it comes back down to testosterone being essentially a barometer of your health. So in other words, good night's sleep, reducing stress, long-term exercise and fitness a la VO2 max, and, you know, your metrics. So in other words, things like, you know, your waist circumference, all of those things go and compound to produce testosterone as a medium to long-term biomarker of your health. But none of the quick fixes work. There is no magic food to do it. There is no magic exercise.

37:30Dr Karan: Yeah, you know, it really troubles me to see the number of hashtags online in these spaces, like, you know, T maxing and, you know, how to, you know, dominate low T. And a lot of this content seems to be targeted towards young men and boys. And a lot of this content sometimes is a funnel to the manosphere. And it really worries me particularly because, you know, if a 19 year old man is assuming his value as a man is represented by a testosterone number, we've essentially just medicalized insecurity and we're just worsening that. Yeah, you're so right. And I want to know how as a medical community, I see it as a partial failing on our part of actually, we need to catch up and engage with the community, these men, and actually put the right information and advice in place, which is why it's so important to be talking about these issues.

38:25Dr Karan: There have been a lot of people talking about their anti-aging routines, which have involved testosterone, clearly supplementing testosterone in super physiological levels. Now, we know from data published in the New England Journal, the Traverse trial, whilst it gives some reassuring cardiovascular information, it doesn't suggest any additional longevity or anti-aging benefit for testosterone. So what are the risks of taking testosterone when you don't medically need it for deficiency? Yeah, great question. And we know that, and this is increasingly studied, that when men take testosterone when they don't need it, it can cause thickening of the blood.

39:05So testosterone stimulates the bone marrow and thick blood can cause increased risk of blood clots and strokes. It slightly makes your blood pressure worse. It can make your cholesterol slightly worse as well. And also it does cause muscle growth and that can include the heart muscle, of course. So So what hasn't been so well studied, but could become relevant in a large population is if you are taking too much, could that actually be triggering a new form of heart disease called cardiomyopathy because of taking androgens excessively? So overall, the message is that, yeah, if you need it and you have a deficiency, a true deficiency, it doesn't cause any cardiovascular risk, according to the first trial.

39:54But if you take it excessively, it's likely to to worsen your health.

40:00Dr Karan: Now, we spoke before about the risks of, you know, short, medium and maybe even long term infertility by inappropriately using TRT and testosterone and these other hormones. Now, I don't know why, but I often see this strong correlation between or sometimes men interchangeably assuming that testosterone equals sperm health and sperm health equals testosterone. And it seems to be a bit bizarre because, you know, whilst they both have this common denominator of the testicle, it doesn't make sense to me that if you're worried about fertility, why you would just measure your testosterone instead of your sperm count and sperm metrics.

40:39Dr Karan: because it's a bit like, I guess, you know, checking the petrol gauge to find out if your tires are working. Why is there that, you know, wrong association between testosterone and sperm? The biggest problem is, is that sperm is just a real pain to measure. It's not a test that you can do postally. You have to do it in person. People don't like doing it. It's a horrible experience for many men to do it. And we are trying to develop better home testing kits that can work. So if you don't do that, then you're left with reproductive hormones, including testosterone, but also luteinizing hormone and follicle stimulating hormone that can give you a bit of a clue, but they don't tell you an awful lot, like you say.

41:22And we're searching for better biomarkers for facility. Yeah.

41:28Dr Karan: And this has been a really enlightening conversation because I think a lot of people need to look at testosterone as a biomarker of their general health rather than just looking at a quick fix and masking any symptoms or any you know causes that may be there by just you know supplementing and then not actually targeting the root cause we talk about root cause a lot especially you know those people in the functional space and you know alternative health space they talk a lot about root cause but sometimes not when it comes to things like trt where actually probably the bigger boring levers, as you mentioned, are things like your metabolic health, other medical conditions, your vices like alcohol and smoking, your weight, your sleep.

42:08Dr Karan: So Dr. Chanajai Senal, thank you so much for joining me and just being really transparent about this space, which I feel needs to reach a lot of people and probably reach the people who are taking these things. No, thank you so much. It's been wonderful to talk and get the message out there.

42:28Thank you.