Note: This is a rebroadcast.

Nietzsche’s maxim, “What doesn’t kill you makes you stronger,” isn’t just a sound philosophical principle. It’s also a certifiable physiological phenomenon; toxins and stressors that could be deadly in large doses, actually improve health and resilience in smaller, intermittent ones. The ironic thing, my guest points out, is that it’s the fact that we’re not getting enough of this sublethal stress these days that’s really doing us in.

Paul Taylor is a former British Royal Navy Aircrew Officer, an exercise physiologist, nutritionist, and neuroscientist, and the author of Death by Comfort: How Modern Life is Killing Us and What We Can Do About It. Today on the show, Paul discusses the science of hormesis, how small doses of intermittent stress can make us more resistant to chronic stress, and why you need to embrace what Paul calls “discomfort harvesting.” We talk about some now-familiar topics like fasting and cold and heat exposure with fresh inspiration as to how important they are to practice and how to do them effectively. We discuss how hot a sauna needs to be to get the benefits of heat exposure, Paul’s suggestion for how to make an ice bath on the cheap, what may be the single best type of food to eat to improve your gut’s microbiome, a form of fasting that’s got anti-cancer benefits but is so accessible it won’t even feel like fasting, what supplement to take to mitigate the effects of a bad night’s sleep, and much more. We end our conversation with how to use what Paul calls a “ritual board” to stick with your healthy habits and resist the “soft underbelly” of modern life.

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Brett McKay: Brett McKay here and welcome to another edition of The Art of Manliness Podcast. Nietzsche’s Maxim, “What doesn’t kill you makes you stronger,” isn’t just a sound philosophical principle, it’s also a certifiable physiological phenomenon. Toxins and stressors that could be deadly in large doses actually improve health and resilience than smaller intermittent ones. The ironic thing my guest points out is that it’s the fact that we’re not getting enough of this sub-lethal stress these days that’s really doing us in. Paul Taylor is a former British World Navy aircrew officer and exercise physiologist, nutritionist, and neuroscientist, and the author of Death by Comfort: How Modern Life is Killing Us and What We Can do About It. Today on the show, Paul discusses the science of hormesis, how small doses of intermittent stress can make us more resistant to chronic stress and why you need to embrace what Paul calls “discomfort harvesting.”

We talk about some now familiar topics like fasting and cold and heat exposure with fresh inspiration as to how important they are to practice and how to do them effectively. We discuss how hot a sauna needs to be to get the benefits of heat exposure, Paul’s suggestion for how to make an ice bath on the cheap, what may be the single best type of food to eat to improve your gut’s microbiome, a form of fasting that’s got anti-cancer benefits but is so accessible it won’t even feel like fasting; what supplement to take to mitigate the effects of a bad night’s sleep, and much more. We in our conversation with how to use what Paul calls a “ritual board” to stick with your healthy habits and resist the soft underbelly of modern life. After the show’s over, check out our show notes at aom.is/stronger.

All right. Paul Taylor, welcome to the show.

Paul Taylor: Brett, thank you for having me as I’m a longtime listener, so it’s great to be on.

Brett McKay: Well, thanks for listening. So you got a new book out called Death by Comfort: How Modern Life is Killing Us and What We Can Do About It. You have an interesting career because you are a neuroscientist who’s also an exercise physiologist and a nutritionist. So how do you end up combining these three areas in your career?

Paul Taylor: Well, it all started, I went to university and did a master’s degree in Exercise Science and then I joined the British military. I joined the Navy and I flew helicopters for a number of years. I also went through combat survival and resistance to interrogation training, which started my interest in this area. And then I ended up doing helicopter search and rescue and I did another master’s in nutrition ’cause I didn’t wanna sort of hang around doing nothing on when we were waiting for the call. And I always had the intention of leaving and starting as a physiologist, a nutritionist. So I did that. I moved to Australia, met my wife in Ecuador, actually she’s an Aussie, dragged me kicking and screaming to Australia and I set up as a physiologist, a nutritionist working one-on-one initially. And then I realized that it wasn’t so much about the science, it was about behavior change. And so that’s why I went on and did another, I went back to university and studied neuroscience. I’m now on kind of topping it off with a PhD in Psychology. So I’m kind of what I call… I call myself an integrationist and a pracademic. So I like to take all the geeky academic research and turn it into practical tools and solutions that people can use, and now I do a lot of corporate speaking and translate that science stem for everyday people.

Brett McKay: All right, so let’s talk about your book Death by Comfort. You argue that the comfort revolution that we’ve experienced for the past 100 years is killing us. How has increased conveniences, increased comfort made us sicker?

Paul Taylor: So we need to start with a fundamental principle here. And Professor Frank Booth, legendary exercise physiologist, said that the human genome has not changed for over 45,000 years. And that the current human genome requires and expects us to be highly physically active for normal functioning. And it’s not just that. So if we take the movement piece, we don’t hunt or gather anymore and we know that the Hadza, a hunter-gatherer tribe in Tanzania in East Africa, the Hadza women and girls take double the steps of women and girls in modern societies, Hadza men and boys three to four times the steps. But when it comes to intensity of movement, they do seven to 10 times the amount of moderate to vigorous physical activity. And what we now understand is that exercise is a very powerful driver of your gene expression. So when we’re not exercising we lose all those positive changes in gene expression that actually help us to be healthier.

And then we have the convenience of food. Now with the rise of ultra-processed foods particularly in the last 30 or so years… And I know Brett in your country 60% of all calories consumed are ultra-processed foods. Australia’s not far behind. And teenagers, American teenagers, 66%. And these things have lots of additives in them that disrupt our gut microbiome, that make us eat more. And it’s these convenient foods that are actually destroying us. And then the other thing is that we live in thermal neutral environments, where we’ve got heating and cooling and we’re no longer cold or hot. And that actually robs us of these ancient biologically conserved mechanisms that protect us and make us healthier when we’re exposed to intermittent stressors of movement and some nutritional stress, but also the thermal stresses as well. So we’re missing these things that are fundamental to our biology.

Brett McKay: Right, so we’ve reduced stress but in the process it counterintuitively increased chronic stress in a lot of parts of our lives?

Paul Taylor: That’s correct. And there’s a whole heap of research that shows that people who exercise and who are fitter deal with psychological stress better. And we also know that exposing yourself to heat and cold just helps with what I call “stress fitness,” and that’s my PhD is now focusing on stress fitness. But I like to use the analogy of physical fitness. So all of your listeners will understand that there’s a continuum of physical fitness. You can be low fit, moderate high fit, or very fit. But you’ve got to do the work. People who are up high on that continuum, they do the work. And you know as well as anybody, Brett, that if you stop training for a couple of weeks, you slip down that continuum. And this is what’s happening with modern life. We’re not getting those inputs that actually build our stress fitness. And then we see we have all sorts of teenagers, young people and older people who are just not prepared for the inevitable stress that is thrown at them in terms of life.

Brett McKay: And so this all goes down to this idea in science, it’s hormesis. Can you walk us through the science of hormesis? What is that?

Paul Taylor: This is my favorite branch of science, and kind of summed up by the philosopher Friedrich Nietzsche: “That which does not kill us, makes us stronger.” So hormesis is defined as sub-lethal exposure to stressors or toxins, which at high levels can kill you, but at low to moderate levels, induce stress resistance. And there are over 600 known hormetic stressors. And so exercise is one, cold exposure, heat exposure, but also the sun UV radiation. You get too much of that, you get skin cancer; you don’t get enough, you get low Vitamin D. We know even small doses of nuclear radiation, which we used to think is damaging, now we actually see can enhance longevity in people. So there are a number of stressors, nutritional stressors as well. Polyphenols, these little things, that compounds that you get in certain foods, mostly fruits and vegetables that are small doses of toxin but actually upregulate our protective genes. So we get a net benefit when we expose ourselves to small doses of intermittent stress because it upregulates our protective genes. So cellularly we become more resilient or increase our stress fitness because of exposure to that small dose of stress.

Brett McKay: Gotcha. And this hormesis, it’s the stress, it goes on a u-shaped curve, right? So…

Paul Taylor: That’s right.

Brett McKay: There’s this you reach a point where you’re going up in the stress and it hits a sweet spot, and then if you keep increasing the stress you start having diminishing returns; it starts going down and becomes detrimental.

Paul Taylor: That’s right, and then it becomes detrimental. And we see that from everything. You see that in exercise. Now that’s starting to come out, that the people who are doing the most… And we’re talking here marathon runners, people who do lots of triathlon, these guys sometimes they actually don’t live longer than people who do no exercise. Now, it’s not all of them. So there’s some individual stuff that we don’t understand, but basically all of these hormetic stressors follow that same curve that you just described. And it’s a little bit like Goldilocks and the Three Bears. It can’t be too little, it can’t be too much. It’s got to be just right. And a lot of our upbringing, it’s too little exposure.

Brett McKay: All right, so let’s walk through some ways we can start adding some more good stress in our life, reducing the comfort in our lives a little bit so we don’t have death by comfort. We’ve been talking about exercise. Let’s talk about this. What goes on in our bodies when we expose ourself to the stress of exercise? ‘Cause it is a stressor. You feel good after a good workout, but when you’re doing the workout it’s actually stressor. So what’s going on in our bodies when we exercise?

Paul Taylor: Yeah, yeah. [chuckle] You’ve hit the nail on the head here, Brett. And I spoke to thousands of people over the years about exercise. Some people go, “Yes, I’m into it.” Others go, “I don’t like it because it makes me feel uncomfortable.” And I say to them, “It’s supposed to be bloody uncomfortable.” That is why exercise is good for you because it’s a stressor that activates these stress response genes that actually protect us. And then there’s another wave of gene expression called “metabolic priority genes.” These are hundreds of genes that are upregulated whenever you expose yourself to the stress of exercise. And then we have other genes that improve our mitochondrial function. So it is by exposing ourselves to moderate intermittent amounts of stress in the body, we’re upregulating gene expression.

And what we now know is that exercise releases a whole host of things called “myokines.” Some people call them “exerkines.” These are molecules that are released from your contracting muscle that we now know get into your bloodstream. They not only affect the muscle, but they get into your bloodstream and affect pretty much every single organ and every organ system in the body in a positive manner. And recent research shows that these myokines or exerkines are carried around the body by these things called “exosomes.” And so it gets pretty technical, but I just want people to understand there are massive changes in gene expression and release of these myokines that then tell the organs and the organ systems in your body to improve how they’re actually operating.

Brett McKay: Yeah. One myokine that people might have heard of is BDNF. What is BDNF?

Paul Taylor: So BDNF, brain-derived neurotrophic factor. And neurotrophic means nerve growth, right? So it helps you to create new brain cells in areas of the brain such as the hippocampus and maybe some other areas, but it also protects the brain cells that you have against damage. And we know there’s a couple of ways that BDNF is released. So there are two myokines that cross the blood-brain barrier. One of them is called “irisin.” And that crosses either from cold exposure or exercise that crosses the blood-brain barrier and triggers the release of BDNF. And then lactate, people know about lactic acid. We used to think that was a waste product. We actually now know that it is fuel for some different cells including our brain cells. And lactate actually crosses the blood-brain barrier and triggers the release of BDNF. And some of your older listeners, Brett, will remember Miracle-Gro in the United States, this stuff that you sprinkle over plants and they would grow like crazy. BDNF is Miracle-Gro for the brain.

Brett McKay: Oh yeah, some other myokines you mentioned in the book, there’s myokines that drive metabolic adoptions such as muscle and bone growth and repair, improved immune function, healthier gut, healthier liver, healthier pancreas. And there’s one myokine IL-6 that has anti-inflammatory effect on the body. So again, the stress of exercise can help reduce inflammation in the long run.

Paul Taylor: Yeah, and this is the thing. So when you exercise there’s a transient increase in inflammation followed by a drop off in inflammation. And often that’s the sort of thing that we see. So you have to look at the long-term benefits of all of these molecules. And the body is just so sophisticated, and we’re still trying to work out exactly what goes on when we expose ourselves to things like the stress of exercise or other different stressors.

Brett McKay: So one thing you do when it comes to physical activity and physical movement, you encourage people to think of their daily activity consisting of three parts: Movement at the workplace, incidental movement, and dedicated. So walk us through these three areas and how can we increase our movement in these three areas?

Paul Taylor: Yeah. So the workplace, I always say to people that if you have a job that involves lots of physical movement, that has got to be worth thousands if not tens of thousands of dollars a year because of the net effect on your health. But lots of us these days have got jobs that involve chronic sitting. And we know that chronic sitting is really, really bad for your health. And so I always encourage people, we know that if you’re sitting for 20-30 minutes plus, there are significant negative changes in your gene expression. So it’s just getting off your bum at least every 30 minutes, I encourage people, and just do some movement. Ideally, the best case scenario, I’ve got kettlebells and clubbells sitting right beside my desk, and every 30 minutes I get up and swing some kettlebells and clubbells around. But if you’re in the workplace, you can just quickly walk them down a couple of flights of stairs.

What that does is it’s gonna create positive gene expression offset the sitting, but it’s also gonna burn up any stress hormones if you’re having a stressful day. Then the other thing I talk to people about the workplace is just look for opportunities to move. And I’ve got a rule that when I’m on the phone I stand up or you can go walking whenever you’re on the phone, and then trying to do things like walking meetings and stuff like that. Just any way that you can add these in. Then when it comes to our incidental stuff, and it is about these little movement snacks and doing, I call them these little “movement snacks,” just one to two minute bursts throughout the day. And I have exercise equipment strategically placed all around my house that acts as a bit of a trigger.

And actually one guy when I did a corporate workshop, it was the second time he’d seen me and he actually said to me, “We have changed our family that when we go into the village for a walk, we actually take the long cut rather than the shortcut.” And I thought, “You know what? That is just brilliant.” How many times have we driven past 30 perfectly serviceable car parks just so we can get as close as possible to our destination? And we’re losing that opportunity to move. And then with exercise, look, I think everybody’s convinced of the benefits of doing more, but for me one of the most important things is to do exercise that you enjoy. That is just really clear from the research that when you find something that you enjoy, you’re much more likely to do it. But also really remember about the benefit of these movement snacks. And researchers call them VILPA, vigorous intensity, lifestyle, physical activity. So these are just little one- to two-minute bursts of physical activity that we do throughout the day that we’re starting to see are really, really beneficial. So it’s not just going to the gym or going for a run; it’s those little movement snacks that are important as well.

Brett McKay: Yeah, you could do movement snacks while you’re watching TV. Yeah.

Paul Taylor: Absolutely. Every time the adverts come on, there’s an opportunity to do movement snacks or just do them while you’re watching stuff. Get an exercise bike and watch your favorite podcast or watch TV while you’re doing some stuff. That’s ideal.

Brett McKay: Yeah, I love the kettlebell. I actually busted out my kettlebell after I read your book and put it someplace in my house that I walked by. I sit down a lot for my job, so I’ve been doing movement snacks with the kettlebell ’cause it’s so easy. It takes up little space and you could do all sorts of things with it.

Paul Taylor: Yeah, they’re just brilliant. I’m a massive fan of kettlebells and clubbells.

Brett McKay: Okay. So move more at work, do more incidental. And the movement at work and the incidental movement, you talk about how a fitness tracker can help with that, right? Counting your steps, seeing your movement, you don’t want to get obsessive about this stuff, but I like the Apple Watch ’cause I can look at it and be like, “Oh, I haven’t really done much today. I’ll get up and take a 20-minute walk.”

Paul Taylor: Brett, I’m exactly the same. I have an Apple Watch and I have my active energy set for 750 calories every single day. And it just, it’s that trigger and it’s just making sure that you’re doing it. And oftentimes, if I’m sitting a lot as well, I’ll look at it and I go, “Oh my God, I just haven’t done stuff.” And it just, it gives you that little prompt to actually go and do stuff. So us neuroscientists will tell you what gets measured gets managed. And I’m a big fan of knowing how much you’re actually moving. That’s really, really key.

Brett McKay: Okay, and with dedicated exercise, pick something you like, just get sweating out of breath frequently throughout the week.

Paul Taylor: That’s it, exactly.

Brett McKay: Okay. Let’s talk about this idea of, you call it “discomfort harvesting.” And we can do that by exposing ourselves to heat and cold. So how can cold showers allow you to do discomfort harvesting?

Paul Taylor: Yeah, so firstly let me define discomfort harvesting. So when psychology, a psychologist will talk a lot about discomfort tolerance, the ability to tolerate discomfort. But I prefer the term “harvesting” because tolerance kind of has the implication that this isn’t that good for me and I just need to kind of tolerate it. Whereas harvesting, you’re actually reaping the benefits. So we know there was a landmark study done in Holland about seven or eight years ago where they took a bunch of workers and randomly assigned them into two groups. And one, they got to have a cold shower at the end of their normal shower for 30, 60, or 90 seconds. And the other group, the control group, just did their normal shower. And they measured their health, their sickness, and their absenteeism. And they found at the end of the year that the cold shower group had a 29% reduction in sickness and absenteeism, which is just massive. Now since that study, there’s been lots of other studies that have shown that there are really huge benefits from exposing yourself to cold water, and it activates something called the “cold shock response.”

So this is an ancient mechanism that as soon as cold water touches your skin, we have neurons just under our skin that send a very quick signal to the brain. And the brain activates this full body response, body-and-brain response to the cold, and it upregulates protective genes. It increases noradrenaline, I think your Americans call it “norepinephrine,” and dopamine in the brain, which are really useful chemicals for motivation and for mood. And we get all of these physiological up-regulations in protective gene expression just from that cold water response. And we know there’s a recent study that showed that if you get into an ice bath at about four degrees, just for 20 seconds, you get a whopping 3% to 500% increase in dopamine and noradrenaline or norepinephrine, which is just huge. And it persists for hours. So it has positive lasting effects on your mood. And we’re now actually seeing people with treatment resistant depression being successfully treated with cold water therapy.

Brett McKay: No, we had a guest on the podcast last year, Dr. Mark Harper, who wrote a book called Chill: The Cold Water Swim Cure. He’s an anesthesiologist, but he swims out in the ocean when it’s freezing. And that led him… He started researching how to prevent hypothermia during surgery, and that led him to research the benefits of cold water exposure and managing the body’s overall stress response. I guess when anesthesiologists put people under, they have to keep the person cold.

Paul Taylor: That’s right.

Brett McKay: It has all this protective benefits. And he started doing the research and the people who do the cold water swimming, they get some of the similar benefits. So yeah, like you said, people who have been able to manage the depression with cold water, exposure decrease inflammatory diseases like rheumatoid arthritis and things like that, all because of cold water exposure.

Paul Taylor: Yeah, and the reductions in inflammatory markers. We cannot underestimate those benefits because if you look at the vast majority of chronic diseases, inflammation, chronic inflammation is a key driver of that. So that seems to be one of the many benefits of this cold water exposure. And we know that you get activation of heat shock proteins and cold shock proteins and changes in gene expression when you regularly expose yourself to the cold. So it’s about getting comfortable with being uncomfortable. That’s what I mean by discomfort harvesting.

Brett McKay: How cold does the cold water need to be to get the benefit? Do we know that?

Paul Taylor: So yeah, actually on my podcast I interviewed Professor Mike Tipton, who is from the UK, would certainly know the guest that you talked about. He’s the world leader in cold exposure, and he reckons that 15 degree water. Now, that’s centigrade. I’m not sure how that translates to Fahrenheit, but 15 degrees centigrade seems to be the trigger for the cold shock response. But I recently saw a research paper where they had people in 20 degree centigrade of water, but they had them in for 20 minutes and they got some benefits. So there seems to be a trade-off between time and temperature. But it’s really, it’s at about that 15 degree centigrade, that seems to be around that area.

Brett McKay: Yeah. So 15, in Fahrenheit that’s 59, about 60 degrees Fahrenheit.

Paul Taylor: There you go, boom.

Brett McKay: And then 20, that’s 68 degrees Fahrenheit.

Paul Taylor: Yeah. And it’s important for your listeners to understand, Brett, that there is a trade-off between temperature and time. So the colder you go, the less time you need to actually spend in it. So I know some people who get into ice baths and they’re in there for at 10 minutes. There’s really no benefit above being in an ice bath for around a minute. The vast majority of the benefits are gonna kick in, no. There’s not really a benefit to staying in as long as you possibly can other than maybe a bit of psychological toughness.

Brett McKay: Is this something you can do every day or should you do it every other day?

Paul Taylor: We don’t have any data on that. Look, I think the best thing, Sonya Sonnenberg did a research study and she found that the optimal dose was about 11 minutes of exposure over a week. So I think we need to see other research replicating or doing similar studies to her until we can say definitively. But let’s take that as a guide for now.

Brett McKay: Gotcha. See, I do a cold shower before I work out. That’s when I do it. That’s what I like to do.

Paul Taylor: Oh, interesting.

Brett McKay: And yeah, but it’s hard to do cold showers or cold baths in Oklahoma during the summer ’cause the water is just lukewarm ’cause it’s like 115 degrees outside. So now it’s starting to cool off and now we’re starting to enjoy it. Yeah, I can’t… I don’t wanna spend $6000 for one of those ice tubs, whatever.

Paul Taylor: I’ll give you a little hack, Brett.

Brett McKay: Okay. What’s that?

Paul Taylor: Get an old fridge freezer. You know one of those chest freezers?

Brett McKay: Yeah.

Paul Taylor: And put silicone on the inside, so you silicone it up. And then you just plug it in on a timer and fill it up with water and run it three to four hours a day. And you can get it to around three to four degrees, and then you just need to jump in. There you go. Boom. Saved yourself $6000.

Brett McKay: We’re gonna take a quick break for a word from our sponsors.

And now back to the show. What’s another discomfort harvesting activity is exposure to heat. Now this is something I do regularly. I’ve got a sauna. I did fork over the money for a sauna. I’ve really enjoyed it. So what happens to our bodies when we are in a sauna or even exercising out in the heat?

Paul Taylor: Yeah. So that increasing core body temperature, again, activates the heat shock proteins, and it’s the heat shock proteins that seem to be the driver of the cellular changes and changes in gene expression. And the other thing that a sauna does is it works as an exercise mimetic. So it seems to mimic the benefits of exercise. So you’ll notice when you’re in an sauna that your heartbeat goes up, your heart rate goes up, your stroke volume goes up. And that’s some of the benefits that we get from low intensity aerobic exercise. And studies out of Finland have shown that people who have regular saunas four to seven times a week live seven years longer than people who don’t. Now, one of the other benefits that you get is around this discomfort tolerance. So with the heat… And I have a sauna as well, I forked out on one, it’s the best money I’ve ever spent. And with that heat, you know that discomfort that you feel when you get really, really hot?

Brett McKay: Yeah.

Paul Taylor: That actually releases dynorphins in the brain. These are kind of like the cousins, the opposite cousins of endorphins. So endorphins are the feel-good chemical, dynorphin is that thing that says, “Brett, this is horribly hot. You need to get outta here.” And it turns out when you activate the dynorphin system reasonably regularly, you actually make your endorphin system more sensitive. So you actually get better feel-good chemicals from other exposures. So that would seem to be another independent effect. But there’s just so many changes from your cardiovascular system and your hormonal system, heat shock proteins that happen when you expose yourself to that heat that we get all of these net benefits.

Brett McKay: Another benefit, we’ve had a guest on the podcast, Charles Raison, he’s a psychiatrist and he wrote a book called The New Mind-Body Science of Depression. And the argument he makes is that one potential cause of depression is inflammation. Not all people who are depressed, but some people who are depressed have increased markers for inflammation in the body. And so what he’s found is if you put these people in a sauna, you have that acute increase in inflammation because you’re sitting in the sauna, it’s a stressor. And then in the long run it reduces overall inflammation and it can help alleviate major depressive symptoms.

Paul Taylor: Yeah, absolutely right. And it’s a little bit like exercising in that you get that transient increase of inflammation and then you get a net reduction afterwards. So yes, absolutely true. And we see that actually a sauna is pretty effective for depression as is cold exposure.

Brett McKay: How hot does a sauna need to be to get the benefit? How long? What’s going on there?

Paul Taylor: Yeah. So look, again we can’t say absolutely definitively, but studies have shown that 80 degrees centigrade again, Brett, you’ll need to do the conversion to Fahrenheit, but at 20 minutes activates heat shock proteins. Now possibly that could be less. This is really about increasing your core body temperature by one degree. And I actually did an N=1 study on my infrared sauna, which only goes up to 70. But infrared, as you may know, Brett, it penetrates deeper into the body, so potentially increases your core body temperature at lower temperatures. I did an an N=1 using a rectal thermometer, which we won’t go into.

Brett McKay: Oh yeah.

Paul Taylor: But saw those benefits. Now that is N=1, but we know that any exposure to significant heat where you caused your body to sweat significantly is going to have those benefits. But if you want the heat shock proteins, it would appear it is around that 80 degrees centigrade but maybe lower for an infrared sauna. And again, it’s a trade-off against time.

Brett McKay: Okay. So 80 degrees centigrade, that’s 176 degrees Fahrenheit. That’s pretty hot.

Paul Taylor: That’s hot. Now, that doesn’t mean… That’s when they saw the increase, but they didn’t in the study look at 70 degrees. So it may be that there could be less than that. And I think that there would be certainly be less than that when you look at an infrared sauna. And actually we’re gonna do some research over here in Australia. I’m collaborating with people over in New Zealand to look into that. So maybe I’ll let you know down the track once we work it out.

Brett McKay: Yeah. So when I do the sauna, I like to go really hot. So I get it to about 180 and then I just do it for 15 minutes, 20 minutes. And then if it’s cold outside, I like to get outside, kind of just be out there in the freezing cold and then get back in.

Paul Taylor: Yeah, the nice benefit of winter. I live in Melbourne in the south of Australia and I have a swimming pool right beside my sauna. And the swimming pool gets bloody cold in winter. So I’ll get from the sauna into the pool, back into the sauna, back into the pool. The only thing I would say, Brett, for people around cold exposure is if you’ve just done resistance training, you don’t want to get into the cold straightaway because it dampens the inflammatory response, and we need that inflammatory response to drive muscle protein turnover. So I will generally do resistance training, get in the sauna. If you get in the sauna right after you’ve done strength training, you get a 3-500% increase in growth hormone. So that’s the one time though that I wouldn’t do the hot-cold, hot-cold. I just want the heat right after the strength training.

Brett McKay: Yeah. That’s why I do my cold showers before my workouts rather than after. Let’s talk about our diets. We kind of mentioned this earlier. How has our modern diet made us sick?

Paul Taylor: Look, this is I think the biggest underappreciated impact on chronic disease, is the massive change in our diet. For all of human history, apart from the blink of an eye, the last 30 to 50 years of human history, we have eaten natural foods that have been alive recently. Now, there is a massive global increase in ultra processed food consumption. And there is a food classification system that came out of a university of Brazil called the NOVA classification that I think is the best ever invented. So it talks about the level of processing that we have, unprocessed foods, I call these low HI foods, low human interference. And I always say to people, look at a piece of food and if you can recognize that it’s been alive recently and minimally interfered with by humans, eat it, it’s fine. Don’t worry about the fat, the carbohydrate, the protein.

But if you’re looking at a piece of food and you’re going, “Mr. Krispy Kreme donut, I don’t remember seeing you running around on four legs,” then it is in your treat food. So I’m not saying never eat it, I talk about the 80-20 rule. And the research that’s come out of NOVA there’s literally around 100 research papers all showing the health risks when we increase ultra processed foods in our diet above around a 20% mark. And you see that 20% mark in countries like France, Spain, and Italy. In America it’s about 60% of calories from ultra processed foods. Worse for kids in Australia, in the United Kingdom, New Zealand, Canada, all more than 50%, and Mexico as well. And it is this massive rise in ultra processed foods. So let’s define it. They are foods that go through industrial scale processing and have lots of additives in them. Not just fat, salt and sugar, but preservatives, artificial flavors, emulsifiers that make them feel great in the mouth. And we know that a lot of these chemicals disrupt our gut microbiome, and that we also ate much more of those foods.

A randomized control trial took a bunch of people, half went on an ultra processed food diet, half were on a normal diet, matched for fat, carbohydrate and protein. They did it for 14 days and then they swapped over. And when people were eating ultra processed food, they ate 500 calories a day more. So what we know about these ultra processed foods, there are amazing scientists all around the world working out what’s called the “bliss point” in the brain. These are certain combinations of fat, salt, and sugar, any two of those three that actually hijack our reward systems and give us a massive hit of dopamine and make these foods addictive or more-ish so we eat more of them. And they’re empty calories. So there’s two mechanisms that happen here. One is you’re eating a lot of crap and that is damaging our cells and damaging our whole processes. But we are also crowding out good foods, things like fruits, vegetables, fresh meats, fish, all of those things that are really beneficial for us. So we get more rubbish in and less good stuff in. So it’s a bit of a double whammy.

Brett McKay: Okay. So your guidelines for countering this food ecosystem we find ourselves in, first one is eat a low HI diet. So low human interference diet. And it doesn’t mean to eliminate all those foods, but 80% should come from low HI diets. So whole foods, oatmeal, yogurts, meats, vegetables. If you eat 80% of your diet coming from that, you’re probably gonna be okay?

Paul Taylor: Correct, correct. And don’t worry so much about the fat, the carbohydrate, the protein. Just eat real foods. And you know the clue? Real food does not have ingredients. Real food is ingredients.

Brett McKay: You also talk about another rule is feed both of your brains. What do you mean by that?

Paul Taylor: So yes, the second brain, the enteric nervous system. So this is basically your gut microbiome. And we know that a lot of neurons reside in the gut microbiome. And there’s a two-way connection between the brain and the gut. And we know that basically if you look at most chronic diseases, lots of neurodegenerative diseases, obesity, diabetes, there are disruptions in the gut microbiome. And we get really good evidence that this is causative. When you look at fecal transplants on either animals or humans, where you can take the gut microbiome of an unhealthy mouse or human and transplant it into a healthy one and they actually develop diseases; or vice versa, you can take an unhealthy mouse, generally we do these on animals, and transplant the gut microbiome of a healthy mouse and the disease disappears. So we know there’s pretty good evidence that it’s causative, and we know that there are certain things that are very beneficial for our gut microbiome.

We’ve known for decades that fiber is good because there are a certain class of bugs in your microbiome that munch fiber and they give off these beneficial short-chain fatty acids that are really good for our heart and our brain and the rest of our body. And what we also know is that fermented foods, so there’s a great study come out of Stanford University a couple of years ago, where they took a bunch of people on the SAD diet as it’s called the standard American diet, and half of them they put on a high fiber diet, half of them high fermented foods. And they measured markers of inflammation, and they actually thought that everybody was going to do better. But what they saw is that some people on the high fiber diet did better, some did much worse. They didn’t tolerate the fiber well. Everybody on the fermented foods diet did better. And what it seems to be is that when we eat fermented foods, they send signals to our gut microbiome to actually be healthier and they proliferate the ones that digest the fiber.

So my takeout from that study is if your diet’s not so great, start to add in some fermented foods like sauerkraut, kimchi, kefir, Greek yogurts, these sorts of things; some cheeses, miso soup, anything that’s got pickles or vinegar. Add that into your diet first bit by bit, and then start to add in fiber and particularly what we call “resistant starch.” And then you’ll create a much healthier microbiome and at the same time reduce your amount of sugar and processed foods, ’cause they’re the ones that really drive an unhealthy microbiome.

Brett McKay: Yeah, I love kimchi. My mouth’s watering just thinking about it.

Paul Taylor: [laughter] Yeah, there you go.

Brett McKay: It’s so good on your eggs. And then resistant starch, that’s found in things like peas, beans, lentils, whole grains. There’s supplements for resistant starch. I know raw potato starch and Hi-maize is another starch that you can supplement with.

Paul Taylor: And banana [0:37:17.1] ____ and stuff like that. Yeah, they’re supplements. But yeah, you get them in peas, beans, lentils, these sorts of things, and the skin of apples and stuff like that. So it’s just eating lots of fruit, vegetables, peas, beans, pulses, those sorts of things.

Brett McKay: And the other rule is embrace nutritional hormesis. What does nutritional hormesis look like?

Paul Taylor: Yeah, so there’s two aspects to this. One is these hormetic polyphenols. And so things like… A lot of people talk about broccoli being superfood and sulforaphane that’s in it. And people talk about it being an antioxidant. It’s actually not. It’s a small dose of poison that creates an antioxidant effect. And we know that lots of fruits and vegetables have these hormetic polyphenols, little small doses of poison that the plants use as protective mechanisms against insects. But because we are much bigger, they just create a very mild metabolic stress. And that upregulates protective genes, things like superoxide dismutase catalase, glutathione peroxidase, these are things that drive your antioxidant defense system. So by eating small doses of toxins that we find in plants, we get a net beneficial effect.

And then the other hormetic stressor is intermittent fasting. And humans have done intermittent fasting unintentionally since the start of time or since we’ve been around anyway. And it turns out that there are lots of beneficial biological processes that happen when we go without food for a little bit of time. We get a cleaning up of our cells that’s called “autophagy,” and we can then switch over, we develop metabolic flexibility. We switch over from running off glucose to running off ketone bodies that can actually be very, very healthy for us. So there’s a whole heap of different fasting strategies, which we can go through some of them if you like, just at a top level.

Brett McKay: Yeah. What are ones that you like, fasting protocols that you like for a beginner?

Paul Taylor: Yeah. Look, for a beginner I think to dip your toe in the water, Brett, there’s really good benefits, anti-cancer benefits from doing a 13-hour night fast. So nil by mouth other than water. And I used to be a late night snacker. And I saw this research that showed that it reduced the incidence of breast cancer and breast cancer recurrence in females when they did a 13-hour night fast. But they also understood the mechanism from animal studies that basically at night when you’re asleep, your DNA repair enzymes are switched on. And these are little enzymes that run all the way through your body, checking your cells, looking for cancerous and pre-cancerous cells. And when they find them, they execute them. Which is pretty cool stuff, right? But when we eat late at night, we have these peripheral clocks in our liver and our pancreas that sense the nutrients and switch off the master clock, and these DNA repair enzymes don’t happen.

So their research said that basically people who eat late at night significantly increased their cancer risk. So I think starting off with a 13-hour night fast. And when I first did this, I’m thinking, “God, how am I gonna get through the night?” So I ran an experiment. I didn’t eat, and I woke up in the morning, and I wasn’t dead. I’m like, “Who knew?” So [chuckle] you just repeat the experiment, right? And you find that it’s just, it’s habit really, and appetite is not really hunger. And then you can extend that if you like to a 16/8 protocol. I’m sure you’ve had people talk about this. This is where you compress your eating window into an eight-hour window and you fast for 16, but it doesn’t have to be 16. It can be those 12, 13 hours, and anything above that is useful.

And then, and I only suggest this for people who are over 40, is doing an extended fast, like a four- or five-day water fast. Because what seems to happen then is when we do that, we get system-wide autophagy. So what happens basically is that when there’s nothing coming in, the body uses this as a cellular sprinkling, and it just goes around in it and it recycles cancer cells, pre-cancer cells, and these senescent cells. These are cells that are supposed to have died but they haven’t really done it properly, and they kind of hang around in a zombie state and they release inflammation. So you get that whole cleanup metabolically and cellularly when you do those extended fasts. And maybe do that once or twice a year, particularly if you’ve got poor health. That can be really good. And what it also does is it kills off our autoimmune cells first. So there can be a real cleanse cellular from doing that.

But I also want to caution people around this. I did intermittent fasting for quite a while and I lost a bit of weight and I was getting DEXA scans, but I noticed that I was losing a lot of muscle. And so for me, this is a trade-off. And because I’m now in my 50s, I do not wanna lose muscle. I’m metabolically healthy. So I’m looking at, okay, so what are my goals here? Well, I know I’m metabolically healthy and I want to be maintaining at least in probably building muscle before I go into my 60s. So I’ve taken a break for a while from intermittent fasting. So I always say to people, What are your goals? If it is about improving your metabolic health, then fasting, go and knock yourself out. But as you get into your 40s, 50s, and certainly into your 60s, you need to be aware that you’re not eating into your muscle mass. So it becomes a bit of a trade-off then.

Brett McKay: Okay. So we’ve talked about some different ways we can incorporate more good stress in our life. Exercise, move more, cold showers, heat exposure, eating better foods, and some of these foods have hormetic properties, doing some intermittent fasting maybe. Let’s talk about rest and recovery. What role does rest and recovery play in adding good stress to your life?

Paul Taylor: So the way I would start to answer that question is by telling people that most of the gains in athletic performance in the last 10 years and certainly the last five years, haven’t been through training methods; it’s been through recovery. So recovery is really, really important to have an athlete being a sustainable peak performer and not dipping into over-training syndrome. And we know that the links between over-training syndrome and corporate burnout are just so deep. The ideology of those conditions is pretty much identical. So recovery is the one variable that we can all use in order to make sure that we stay in optimal health, particularly if we have stressful lives. And a little tip here, a little kind of a preview, is that recovery is not sitting with your feet up watching Netflix, drinking a bottle of wine or half a dozen beers. That is relaxation. So they’re very, very different.

So I think recovery here is absolutely fundamental. And with recovery, I’m talking about things like exercise, like the cold and heat that we talked about, but also breath work and sleep hygiene and taking regular, I call them “brain booster breaks” throughout the day. Do a little burst of exercise, and then to do one to two minutes of breath work, drink a bit of water. That is like taking your brain out and then plugging it into the wall to get a recharge. And then when we talk about macro recovery, that’s about sleep. And having good sleep hygiene practices are critical because when you’re asleep, that is when your brain cleans out the toxins. The brain actually doesn’t have a lymphatic system. It’s got a glymphatic system that starts with G, and that happens at night. That’s when we clean our brain out of toxins. And we know that sleep is so important for biological repair.

Brett McKay: I don’t know if you know anything about this, but something I’ve been thinking about when it comes to sleep is, I wonder if there’s any hormetic benefit for occasionally having a crappy night’s sleep or even like pulling an occasional all nighter. ‘Cause when I think back to caveman days, I don’t think people really slept very well. They didn’t have good sleep hygiene, right? You’re sleeping outside, around a lot of people, there’s crying babies. I don’t imagine them having the best sleep compared to where, you know, us, we have… We’re in a dark 60 degree room with the Eight mattress and all this stuff.

So I wondered if there is a benefit of sometimes having a crappy night’s sleep. Maybe we’re made to handle the stress and little doses can be good, maybe.

Paul Taylor: Yeah. And look, we don’t know. So these are the things that there are… That hormesis works in mysterious ways. But what I would say is there may be a small benefit, a small hormetic benefit to a little bit of a lack of sleep ’cause we know that there are some physiological changes that potentially could be beneficial. But again, it would be very intermittent if there was and having consistently good sleep, just because there are so many fundamental biological processes that depend on having good sleep. So yes, having a bad night’s sleep every now and then, certainly not as bad as some people might think. And I would caution people again, we talked about Apple Watches earlier on, that research shows that say, Brett, have me and you in the study, and it was engineered that we both have five hours of sleep a night. If they tell you that you had good sleep, and they tell me that I had bad sleep, but we both had the same, and then we do test of cognition, you will do much better than I would.

Brett McKay: Yeah.

Paul Taylor: So a lot of this can be the placebo effect that when you look at your watch and you go, “Oh, I had bad sleep,” you automatically then your mood decreases, your cognitive performance decreases. So just be overly wary about looking at watches because they are guessing. Basically they’re using heart rate and movement to try and guess when you’re asleep and what stage of sleep that you’re actually in. The best indicator is whether or not you wake up feeling refreshed.

Brett McKay: Right. Or even if you don’t wake up feeling refreshed, you could have had like enough sleep for what your body and mind needed. I’ve had those moments where I slept solid seven hours, but I’m just like feeling groggy and not great. And I think, “Oh my gosh, my workout’s gonna suck today. I’m gonna have a bad… ” But I ended up like crushing it in the gym, work was great. I just… Yeah, I never like that word, the opposite of placebo is nocebo.

Paul Taylor: Yes. Correct.

Brett McKay: So you never nocebo yourself. So if you had a bad night’s sleep, just don’t worry about it.

Paul Taylor: That’s right. Just get… And you know a brilliant little hack, Brett? If you have a bad night’s sleep, take some creatine. Because creatine monohydrate… So think of our energy systems. We got ATP-PC, we got the lactic acid and the aerobic energy system. And creatine plays directly into ATP-PC. It’s phosphocreatine. And the research now shows that creatine is really good for the brain. All of your cells use creatine, but I’ve got research papers which I can flick you and you can put them in the show notes, that shows that if you take creatine after a bad night’s sleep, that minimizes the negative effect on brain function.

Brett McKay: That’s cool. I didn’t know that. So you offer some concrete advice on how to put these practices we’ve talked about today into routine action. We were talking about earlier, a lot of the work of a trainer or a coach, it’s behavior modification. So you have to think a lot about this. And one idea that stuck out to me was this idea of the ritual board. What is a ritual board and how can it help someone create healthy habits?

Paul Taylor: Yeah. So a ritual board, I kind of stumbled across this thing. I created it when at the age of 41, I decided to become a professional boxer, which to my wife’s disgust. But I put my goal on the ritual board to be a professional boxer. And I put my Why. So for me, always connecting a goal to a deeply held value is really important. And my Why was authenticity. But then I’m saying, okay, what’s the process that I need to do? And so I put down a whole heap of things that I needed to do. Again, going to a boxing trainer starting three times a week, going up to six; doing my runs, doing my visualization. And then I had a whole heap of little movement snacks on there. And so this is all about the process. So we have goals but then we have a process. What are the habits that we need to do to get it?

And you write these all down on a board. I just use an A41I. I’ve got one right beside my desk. And you have a weekly target for each of those things. Now the key thing is have some hard ones on there. Go and do a workout. Go and do some healthy shopping. And then when you’re highly motivated, do the hard stuff. But you’ve gotta have lots of easy ones there. So put on, I might do a hundred kettlebell swings a week, but you can do them in blocks of 10. So then when you look at your ritual board, you just go, “Hey, I’m just gonna go do 10 kettlebell swings,” and then you tick it off, you write down, “I’ve done 10.” And that creates a feedback.

So what… This is all based on the work of BJ Fogg, Professor BJ Fogg, brilliant guy in terms of behavior change. And you need a trigger to do the behavior and you need a feedback mechanism. And this ritual board acts as both. ‘Cause when I see it sitting beside my desk, it becomes a trigger to do something. And then when you tick it off, that is giving you feedback that actually you are making forwards motion towards your goal. And the big thing I had my epiphany on that was I realized the more I was interacting with it, the more motivated I was getting. And then I’m like, “Oh, you mop it.” The natural rewards for the brain: Food, water, sex, nurturing, and achievement. And so when you achieve something, and especially when you tick it off, that releases a bit of dopamine, and dopamine is the chemical of motivation. So what we now know is that motivation follows action, not the other way around. And lots of people are waiting for the motivation fairy to come along [chuckle] and give them a big doll up of motivation before they get started. The motivation fairy is the ritual board. That’s what I found.

Brett McKay: Yeah, you have a picture of your ritual board in the book, right? So at at the top you’ve got your goal and then the why of that goal. And then you have these rows of these different exercises that you want to do throughout the week. And then each exercise has a numeric goal for the number of times you want to do that exercise during the week. So on yours you have, you got bag work 12 times a week, chin-ups, you’re gonna do 50 reps during the week; sumo squats, 200. And then you have calms for each day of the week where you can write down how many times you did the exercise that day. And the goal is you wanna do enough each day so you hit your weekly goal. So basically with this ritual board, you’re gamifying your goal.

Paul Taylor: Absolutely. And the key thing, Brett, is you gotta have lots of easy ones on there. So you interact with it and have it somewhere where you will see it regularly. So my original one was on my bathroom mirror. I’ve also had times in the kitchen. Now I have it right beside my desk ’cause I spent a fair bit of time at my desk.

Brett McKay: Did you become a professional boxer?

Paul Taylor: I did. And I’ve now retired undefeated, 1 and 0.

Brett McKay: Do you box at all like just sparring, just [0:52:41.0] ____ stuff?

Paul Taylor: I do a bit of but I’m kind of, I was tempted to get back into it, but just there’s so much research about the negative effects of repetitive trauma to the brain. And it doesn’t have to be massive. So it’s something that I love, but I do very, very intermittently. I’ll do plenty of boxing training, but the sparring I’ve kind of backed right off from because I wanna have a healthy brain when I’m in my 80s and 90s.

Brett McKay: Well, that’s cool. You did that when you were 41. That’s really inspiring that even if you’re in midlife, you can still do something big like that.

Paul Taylor: And I think the part of this, Brett, is that we do need to do hard stuff. And so I generally, every decade will go out of my way and do something that is really, really challenging. I’ve also gone to the Amazon and had a three-week trek deep into the Amazon to visit Matis Indians and went through a rite of passage there. So every 10 years or so, I do a really hard challenge just to make… Just really to counter that development of the soft underbelly that we get with modern life.

Brett McKay: What do you got scheduled for your 50s?

Paul Taylor: So my wife has actually thrown one to me, and it’s made me really uncomfortable. And I know, she said to me, “Why does it always have to be physical?” She said, “Why don’t you go and do a five-day or a 10-day silent retreat?” And for an Irish man, we are talkers. That [chuckle] makes me very uncomfortable. So I think that’s gonna be my next one.

Brett McKay: I love that. Well, Paul, this has been a great conversation. Where can people go to learn more about the book and your work?

Paul Taylor: So probably my website paultaylor.biz. I also have a podcast, The Paul Taylor Podcast. And Instagram, I’m @paultaylor.biz on Instagram. And then you can find my book. Most of your listeners I think will be in the States, and just on Amazon, Death by Comfort.

Brett McKay: Fantastic. Well, Paul Taylor, thanks for your time. It’s been a pleasure.

Paul Taylor: Thank you very much for having me. And I would like to say just, I have to say this, Brett. I have to give you a thank you from my wife because I listened a few years ago to you interviewing Gregg Krech from the ToDo Institute…

Brett McKay: Oh yeah. Yeah.

Paul Taylor: Right? And I sent it to her and said, “You need to listen to this guy.” ‘Cause my wife’s a coach. And she listened to it, she loved it, and she went and studied with Gregg for a year on Japanese psychology. And she’s been doing that for a couple of years and practicing with our clients and getting brilliant results. So thank you for that. You’ve had a big impact in our household.

Brett McKay: Well, thanks so much for letting me know. That’s great to hear. Gregg, that’s one of my favorite interviews that we’ve done.

Paul Taylor: Oh, he’s awesome. I’ve had him on my podcast twice. I had him on just two weeks ago. He’s just, he’s brilliant.

Brett McKay: Fantastic. Well, Paul, thanks for your time. It’s been a pleasure.

Paul Taylor: Thank you.

Brett McKay: My guest today was Paul Taylor. He’s the author of the book Death by Comfort. It’s available at amazon.com. You can find more information about his work at his website paultaylor.biz. Also check out our show notes at aom.is/stronger where you can find links to resources. We delve deeper into this topic.

Well, that wraps up another edition of the AOM Podcast. Make sure to check out our website at artofmanliness.com where you can find our podcast archives as well as thousands of articles that we’ve written over the years about pretty much anything you can think of. And if you haven’t done so already, I’d appreciate it if you take one minute to give us a review on Apple Podcast or Spotify, it helps out a lot. And if you’ve done that already, thank you. Please consider sharing the show with a friend or family member who you think will get something out of it. As always, thank you for the continued support. Until next time, this is Brett McKay reminding you to not only listen to the AOM podcast, but put what you’ve heard into action.