Interview with Dr. Jack Kruse: Neurosurgeon, Cold Thermogenesis, and Leptin Reset

Buckle up, ladies and gentlemen… here is the much-anticipated interview with Dr. Jack Kruse: neurosurgeon, epic biohacker, cold thermogenesis guru, weight loss success story, and (in)famous Paleo rockstar. Unless you’ve been… living in a cave… you’ve noticed that Dr. Jack has recently ruffled some feathers and caused a powow in the Paleosphere.

Wait, what does a neurosurgeon have to do with cavemen?

For the edification of those of you who don’t know him, Dr. Jack Kruse has a pretty cool story. Yes, he is a board-certified neurosurgeon – a rockstar when it comes being fist-deep in brains – who practices in Nashville, Tennessee. But he’s no normal doc. He gave up his post as a top neurosurgeon because he decided his profession – and he – wasn’t doing the job. Several years ago, pushing 350 pounds, his own health was in question. As he says in the podcast:

“I was no good example for my patients. All you had to do was look at me – I was a complete fatass. And I said, you know, In order for me to change the culture of medicine, I have to first change the culture of Jack Kruse. And that’s what I did: I changed me. I became the change I wanted to see in my profession.”

So he left his post to start his own practice and promptly biohacked himself with leptin and cold thermogenesis to lose over 150 pounds without exercise. He decided to launch a blog (check it out here) to disseminate his theories and protocols, which in only 8 months has soared to being one of the top 100,000 in the world. He even snuck past Dave Asprey at And that guy practically invented the internet.

Jack’s Frozen Biohacking

Jack does extreme biohacks… He has been known to write blog posts outside in below-freezing temperatures buck naked, inject himself with staph infections, and pack himself in ice for hours. This is not a normal man. And that’s one of the things I like about him. I even heard him sloshing around in the background during the interview. I don’t want to know what was going on the other end, although I’m guessing nakedness, an icy bathtub, and shrinkage might have been involved.

To me, Jack’s work is especially interesting given my background in Psychological and Brain Science research back in my Dartmouth days. There’s actually a bit of overlap between what he’s doing and my newest book that explores the evolutionary basis of the faculty of music, “The Musical Brain.” And there’s a bit of a rebel in both of us, although mine might be slightly better behaved.

Hanging out with Jack before and after our panel at PaleoFX, it’s clear that he truly cares. Jack answers every question and comment on his blog. For a busybodied brain surgeon running his own practice, that’s very cool. Some of his posts have over 1300 comments from loyal fans and rabid critics.

But, as Jack says on my show, “I’m not in this for anybody to like me. I’m in it because I want to save your life and I want to make your life better. I’m just asking you to think.”

Being Directionally Accurate

In this interview, I talk with Jack about something that’s incredibly important that I borrowed from my days as a private sector strategy consultant: the significance of being directionally accurate. What does that mean?

I look at it this way: Jack is onto something. How else could he inexplicably lose 140 pounds 11 months (with similar replicated results in and out of his practice)? Is he absolutely correct about everything? No way. Am I? Hell no. Are you?

Stop hating. Either ignore Jack or give a few of his protocols a shot and decide for yourself.

No one will be 100% correct 100% of the time. We need to do what we can to cite well-researched science when it is available and guinea-pig when it’s not to see what works.

A bit of cold with a smattering of ketosis won’t hurt anyone.

Alright, here comes the show. I pick Jack’s brain about:

  • Why cold thermogenesis and the leptin protocol enables miraculous fat loss (Jack lost 77 lbs. in 3 months and 140 lbs. in 11 months without exercise)
  • How harnessing the cold pathway can help you sleep like a rockstar, lose weight, and increase your lifespan
  • What Lance Armstrong, Michael Phelps, astronauts, and Sherpas have in common
  • The biological and evolutionary basis of the cold pathway (geek alert)
  • Why it’s important that the much-awaited “Factor X” is linked to the cold
  • Why being directionally accurate is more important than being perfect when it comes to making progress

Jack is a wealth of information about evolutionary theory, the brain, and fine wines. On top of that, he’s a cool dude, and we’ve had some fun. The man speaks his mind. Have a listen…




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Jack Kruse Interview Transcript

Abel James: Hi there. Welcome to the Fat Burning Man show. I’m your host Abel James and ladies and gentlemen you’d better buckle up because this is the much anticipated interview with Dr. Jack Kruse, neurosurgeon, epic biohacker, and cold thermogenesis guru. Unless you’ve well been living in a cave, you’ve noticed that Dr. Jack has recently ruffled some feathers and caused a bit of a powwow in the paleosphere. So, we’re going to be talking about some controversial topics as well as covering how Jack enables miraculous fat loss and weight loss and increases in health. You know Jack himself lost well over 100 pounds in less than a year using no exercise. So, we’re going to geek out about brain stuff, talk about safe starches and other taboo subjects, and have a bit of fun. So, without further ado let’s go hangout with Jack.

Hey, Jack. What’s cooking in Nashville?

Dr. Jack: I’ve spent a lot of time actually talking to my surgical team about my TED Talk because some of them wanted to see the video and then I actually started to show them some of the videos that I’ve done on several of the patients that I’ve used pre op and post op photos on and they were just floored.

Abel James: I bet.

Dr. Jack: I just had a lady come in yesterday that I did a tumor with and we used three weeks of pre op CT on her and she came back to see me. She’s only eight days out and the incision goes right through her armpit, so it’s you know it’s a very sensitive area. She sat on camera. All she took was two Tylenols in the first week.

Abel James: Jeez.

Dr. Jack: You probably know all the bullshit that’s going on it the paleosphere about this. It just amuses me so much that these guys are mentally masturbating over rats and rodents and here I am approved this shit on myself and now I’m actually using it to help people and it’s unbelievable what’s  going on out there.

Abel James: That is so cool. Yeah, you know I don’t even keep up with a lot of that paleosphere nonsense. You know, I’m never really on paleo hacks or anything like that. I don’t know. It’s a lot of arguing and as much as I have to use Facebook and Twitter I’m not really good at it and I don’t really do it that much. I guess it kind of comes with the territory of being a small town New Hampshire boy at heart.

Dr. Jack: No and you’re probably smart for doing that. I have to tell you. I told you when I met you, I’m not a technology guy by any stretch but I have gotten to use Facebook and Twitter quite a bit. I’m still not what I would say is up to speed on the Twitter thing, but because my blog has grown so much I didn’t even realize until I came home from PaleoFX. Dave Asprey actually sent me a personal e-mail and told me that my blog has more traffic that his now.

Abel James: Are you kidding me?

Dr. Jack: No, I’m not. I didn’t know this. Cause he asked me could he start advertising a bulletproof coffee on the site. I said “Yeah, I don’t give a shit.” The only place I don’t have as big a following, he does his internationally but me and him are gonna kinda partner and try do some things because I think it’s become pretty clear that the tact that I’m taking is actually kind of what he is doing in terms of biohacks.

Abel James: Yeah, totally.

Dr. Jack: And the biohacks I’m doing are pretty intense. You know, people are just not ready for what I’m bringing to the table. But, I guess they don’t understand that as a neurosurgeon who’s in the middle of mediocrity in this species I’ve got to do something you know to help these people. And reviewing articles on rats all day on a blog that just doesn’t cut it. It doesn’t. I’m sorry.

Abel James: It’s funny how many rabbit holes there are. And it’s funny because a lot of these people totally get caught up in this little minutia which is almost bringing a whole field backwards. You know just kind of rehashing these things that don’t really need to be talked about a whole a lot instead of moving forward and trying new things and accepting some of the things that we’re never going to know with 100% certainty if this stuff works and nothing is ever going to work on anyone, but like it’s obvious that your results are there and it works at least on some people and you’re trying all this awesome stuff. So, there’s no use arguing about any of this crap.

Dr. Jack: Well, you know the funny thing is they do, they continue, and I keep giving people examples in modern life where what I’m saying is actually shining through a little bit. And they want to act like, “Well, everything you say has to be absolutely spot on otherwise everything you say is invalidated.” And I’m like “Really?” I just saw a comment today. I’ll give you a perfect example. One of the, what’s her name? Melissa McEwen commented that “If he’s going to put this theory out then he has to have some proof.” And I’m like “Really? If you go back and look at Einstein’s paper from 1905 there’s not one footnote in it. And the reason why is what I’m saying to everybody, and this is what I think people have a hard time with. I’m telling you that I found a pathway in our brain that dates all the way back way, way, way, way back that none of us a privy to. We haven’t known about it and no one’s written about it. Well, how am I going to have a paper to cite in that case?

Abel James: Well, and to some degree when you’re ahead of the research, how can you have the research support you, right?

Dr. Jack: That’s the way I look at it, but I guess my sensibilities are just a little bit different than everybody else’s and I know this experiment that I just did with the TED Talk is really, I mean I’m actually surprised at how freaked out people are by this.

Abel James: Really? So, what was the response to the TED Talk? I did watch it by the way.

Dr. Jack: Well, I was actually going to e-mail you earlier today and tell you to read Richard Nikoley’s blog. He did a blog, but he was very smart about it. Richard thinks that I’m on to something, but you have to realize he’s closely aligned with Kurt Harris, Emily Deans, and Melissa McEwen so he does not want to come out and give me the stamp of approval because right now I’m the guys with the target. I’m the bad guy. I’m the guy ruining paleo and all that. But, he calls me up out of the blue yesterday and says, “Look, I’m thinking about writing a blog post because people don’t know this about me but I’ve been doing a modified version of CT myself for years and it’s really worked.” He said, “So, I’m really intrigued by what you’re doing.” But, he goes “I have a different angle” and he goes “If you give me some leeway and let me post this blog and see what happens.” Well, the blog’s got almost 400 comments and if you read the comments they are incendiary. I mean they are unbelievably incendiary.

Abel James: So, this is his following, right? So, people who may not have heard of you before? Like they probably have, but most.

Dr. Jack: Yeah, these comments are from Harris and Dean’s. They’re bad. They’re really bad and Richard and I talked about it and I even baited a couple of the comments on my Facebook page. I knew that the usual suspects would come out, so I made a threat on my public Facebook page to bait the hook and dude they all took it hook, line, and sinker. I told Richard, I said “Look, just do what you want.” But, here’s the cool thing Abel. I told Richard what Factor X was and it stopped him dead in his tracks.

Abel James: Did he write about it?

Dr. Jack: No. I told him he’s not allowed to talk about it because here’s the thing you don’t know and I’m going to tell you this, Richard out of the blue happened to call me on January 9th the day of the epic biohack while I was packed in the ice and that’s how he knew about what I was doing, but I told him not to talk about it to anybody and I have to give him credit. He never said a word up until you know the TED Talk. And I told him “Once the TED Talk was out you can tell people.” And that’s what I think decided for him to post this blog because he knows what I’m doing has some credibility, but when I told him Factor X he was blown away.

Abel James: That’s freaking awesome.

Dr. Jack: And he’s like, “Dude, this is going to be big.” He says “Why don’t you just release it to get the heat off you?” I said, “Dude, you don’t understand. Good and bad publicity is good because you know what? They’re all talking about me.”

Abel James: That’s true.

Dr. Jack: It doesn’t matter. I mean if you look at my traffic it’s fucking ridiculous. I mean I’ve only been blogging eight months and I’m in the top 100,000 in the world.

Abel James: Yeah, that is bonkers. That is just completely unprecedented.

Dr. Jack: Well and you know all I’m doing, here’s the thing that I think separates me from everybody else, is I’m not regurgitating papers. My stuff, this is coming out of my head. This is stuff that I’ve physically done on me. You would think that people would stop and say “This dude lost 157 pounds like rewiring his brain, using his gut, circadian biology, and cold.” That alone should give me some credibility, but no I’m crazy.

Abel James: Well yeah and that’s one of the things that I wanted to talk to you about today because actually I originally started interviewing people who had inspiring weight loss stories and most of them are pretty actually Jimmy Moore was one of the first guys on my podcast and a few other people who lost like over 150 pounds like David Garcia. And actually, I had Richard Nikoley on also, but most of those people aside from Richard and I guess Jimmy to some degree it wasn’t like a paleo thing. It was a story about inspiration and fighting on the treadmill and all of these things like that and not to say that I support that or condone it or anything like that. It’s just like an inspiring story because they’re losing weight. Now yours is completely different. You lost like 133 pounds in 11 months then 167 a few months later. That’s insanity and you weren’t spending that time on a treadmill or getting your stomach like stapled right?

Dr. Jack: I didn’t exercise one bit through that whole thing. That is to me and I will tell you Abel I haven’t really told a lot of people that. I’m telling you that and this is why I can say it loudly now because I’ve laid the foundation in the CT series. If you realize, and I told you this while we were at that picnic, that a polar bear comes out of the ground completely shredded with big muscles after he hibernates. Why? He doesn’t have any time to exercise because what he’s subjected his biology to is sleep and deep cold. That is precisely the path that I used to lose the weight. The only thing that I added to the mix was the Leptin prescription. I utilized my own Vegas nerve to rewire my hypothalamus.

Abel James: So, for you, which one came first? Was it Leptin or the cold?

Dr. Jack: Well actually they came together because if you understand how I came to the genesis. Like if you listen to the TED Talk, I told you I was at the foot of Michelangelo’s David where what inspired me or I should say what was the spark of a flame was I looked up at him. I was standing behind the statue while everybody was in front of it and I said “What’s the difference between perfection and my fat ass?” And I realized what it was, was the world that he lived in was radically different than the world I lived in. And from that spark of reality I realized “You know what? I think what may be the difference is circadian biology.” And from that one thing led to another and literally I had a 14 hour plane trip home. I started writing down all these ideas on the plane trip. To this day, I can’t even tell you what happened on my trip in Italy from that day forward until I came home because that’s when I wrote my document. That’s when I came up with the Holy Trinity blog post. That’s when I came up with the Ancient Pathway because I knew the ancient pathway existed in my neurosurgery books. The problem was I didn’t know how to get into it or out of it. Like there was no neuro wiring in or out and I said “This doesn’t make any sense that we don’t have neuro wiring going in and out.” I said “There’s got to be a way to access this pathway.” And when I realized it was circadian biology, then I said “Okay, I’ve got to look for a link.” And when I found the link I was like “Holy shit.” Dude, it’s cold.

Abel James: Yeah, I totally get off on that stuff too because it’s like you know I think I told you that my background it’s an undergrad at Dartmouth was psychological and brain sciences. And actually I just put out a book yesterday.

Dr. Jack: Dude, I was going to tell you that. When you posted the video I didn’t know that you were that talented.

Abel James: Oh, thanks.

Dr. Jack: That’s rocking.

Abel James: Last year I played like 250 shows, went on tour. I’ve toured a bunch of times. I’ve went all over. I have many separate lives. I’ll send you a copy of my book too. I think you’d find it interesting. It’s about the biological basis of the faculty of music and how the brain of the musician is distinct from that of the non-musician.

Dr. Jack: I would love it read it.

Abel James: Oh, for you guys out there, it’s free until Friday. I’m not really sure where I’m going to post this, but I just put this out. And it’s funny because I actually wrote that a few years ago Jack and it was when I was deeply entrenched in the science of it all and this kind of gets back to what you were talking about earlier about like how do you cite all of the research when you’re kind of ahead of the field. So, I went and revisited this and basically put an intro and a conclusion and what I say is in essence “We already know enough about the history of music and the neuroscience and whether or not it’s important.” You know, but we don’t necessarily need all the science behind it. It’s a gift and we should enjoy it. And the thing that I learned when I was studying science was like that number one, neurons fire. Number two, we have behavior. And then no one really knows what happens in between. Despite all the research out there we’re still looking for that thing, that magic that happens in between. You know what I’m saying? I think that’s what you’re after and that’s what we need to be chasing after that instead of going backwards and trying to just recite research.

Dr. Jack: Well that’s part of what my ultimate, well I guess I wouldn’t say my ultimate plan. I think it’s what kind of happened to me at the foot of that statue. It kind of changed my perspective because as a neurosurgeon, someone who was trained to think reductively, it kind of opened my mind to “You know what? I need to start thinking vertically and horizontally like I did when I was a kid.” And it took me back. It really took me back to the time that I spent in the Museum of Natural History in New York. And I have to tell you, I will never forget the day in my life when I came up with the entire theory in Factor X and I sat there and I thought to myself, “This is going to change medicine. This is going to change everything because we finally have an epistomalogic foundation for what modern medicine is because if you look at like the last 120 years, all the randomized controlled trials that we have, every single one of them are flawed. I mean, we kind of all know that. I mean if you remember from that magazine article that was written. I think it was written in the Atlantic a couple of years ago about medical lies and research. This guy wrote an article and basically he took out the best randomized control trials and every single one of them were cooked. You’ve got to look at that kind of data and this guy is a big time medical researcher and then we get all of these mental masturbating comments in the paleosphere about this study and that study and I guess I just look at it not from the 30 foot view anymore. I look at everything from a way bigger view. And I guess maybe that’s why people have such a problem with the way I think cause I don’t consider this a theory of everything. Actually, looking at this very specifically from mammalian bio chemistry and why do we still have these pathways built into us when we know we evolved in warm but yet these cold pathways are in us. I mean someone’s got to explain you know Phelps, the Sherpas, the NASA astronauts, me. You know these things that I’m finding in patients. You know it just doesn’t magically come up and here’s the irony for me. Here I am in the clinic now using what I learned on myself on January 9th and helping people and they’re kind of floored. They’re like, “I can’t believe this actually kind of worked.” And I’m sitting back and it’s just the coolest thing that I’ve ever seen happen. And you know the hack that I did on me is not the hack that I’m doing on people. It just gave me an understanding that there’s something in us, in our brains, in our central and peripheral nervous system that is pretty damn special and it was put there by Mother Nature and it was put there for a reason. And if we understand it, it could actually change the way that we look at many of the Neolithic diseases that we face today. I mean you know it and I know it that there are so many diseases out there that my profession has no answers for you know like autoimmune disease, cancer, diabetes. I mean we’ve been studying these and throwing tops of money on it and we’re nowhere closer to it. We have a country of 60 million diabetics now that are basically dying faster than they’ve ever died before. We are seeing this disease show up in kids and what are we doing? We are treating it with insulin and medicines. You know that’s just it’s not getting them any better. The core trial data shows that people are dying, even with the best medical treatment, six years earlier than they should.

Abel James: Yeah, it’s bonkers.

Dr. Jack: We’re doing something wrong.

Abel James: Yeah. It’s a Band-Aid on a severed limb.

Dr. Jack: That’s a great analogy.

Abel James: One of the things that I was interested in Jack was you are very specific in your blog and all of the blog posts on comments about how to do the cold thermogenesis and how to run the protocol on yourself, but is there like an 80/20 of that for just like a normal person who wants to dabble in it a little bit to get some of the effects without going totally for the whole protocol?

Dr. Jack: Yeah. I’m going to give you the two answers here. One of them you won’t like, but I’m going to give you the answer you really want second. The first one is probably my smartass answer.

Abel James: I’m ready for that.

Dr. Jack: The theme of my website is “optimized life.” When I have an “a” available to me I don’t shoot for a “b, c, or a d.” That changed in my life when I was at the foot of that statue. I used to settle. I don’t settle anymore. So, I would tell you for me and for the people that I actually take care of in my clinic in Nashville, that’s the way I roll. The protocol is the way I roll. Now, for a guy like you since I’ve met you and I’ve met your significant other, I would say for you guys yeah I think you can dabble in it, but here’s the difference. Most of the people in the paleosphere are eating a pretty solid diet. That’s not true of the people that I’m seeing in the clinic. So, I really need to get them to adapt to the appropriate diet first. For you guys, you’re already there. The only thing that I need to kind of convince you to do is maybe tweak the diet a little bit. Make it a little bit more ketogenic and probably add  more seafood or krill oil as a supplement and then I’d say yeah you can do CT a couple of times a week. You could even do it kind of like Richard Nikoley talks about doing. And what I really want for people to do is you know everybody has no problem giving Robb Wolf or Mark Sisson 30 or 60 days of trying something and get the benefit of the doubt, but they have a really hard time giving me the same you know leeway.

Abel James: Well, this is new.

Dr. Jack: Right. Well, paleo is new too. Is there a randomized controlled clinical trial that shows that paleo is better than anything else?

Abel James: You know I guess that’s true. I actually came to paleo ideals you could call them these days kind of independently by reading at least from the macronutrient perspective like old body building textbooks from the 70s and the 80s and stuff like that you know. So, it’s like these principles, some of them at least, have been around for a while and the whole real food thing has too, but I mean the cold thermogenesis it doesn’t really have those same roots.

Dr. Jack: No, I disagree. It does.

Abel James: Really?

Dr. Jack: Oh yeah. It’s out there. It’s in a lot of cultures. It’s in the Indian cultures. It’s in the Chinese culture. Tibetan monks.

Abel James: As a therapy?

Dr. Jack: Yeah. In fact if you remember when we were at PaleoFX I wrote in my blog post, the number one thing that affected me was a guy named Mitch Baird whose grandmother was a Shaman and he floored me and started crying. Actually, after my hour long talk and told me that his grandmother was doubted by the white man in the 1950s and one of her treatments for people with diabetes was to cut holes in the frozen ice and put their people in it.

Abel James: Really?

Dr. Jack: Oh yeah, it’s if you go back and read my blog post Abel on my top ten things that happened at PaleoFX that was number one and believe it or not I’m getting ready to do a video blog post with his grandmother. She’s in her 80s now.

Abel James: That is so cool.

Dr. Jack: And when I heard that at PaleoFX I was just so taken back. I mean he brought me to tears with the story. I mean he was crying like a baby. And in fact, it’s so funny. Before we come on today he sent me a message today that his grandmother is actively getting ready. She’s going to put together all the things that she used to do prior to 1950 for his people up in the eastern part of the northern part of Canada where these people are located. And I’ll tell you, there’s a lot. There’s a lot that’s out there. Here’s another thing that I wrote about in CT six that I don’t know if you’re aware of and I wasn’t aware of it until I actually started doing some of my homework. Albert Schweitzer won the Nobel Prize in the early 1900s. He actually went up before Weston A. Price. I think it was in 1913 or 1911 he actually saw them. There was no documented history up there of them ever having heart disease or having cancer at all. And remember, this is when they were cold adapted, eating the cold adapted diet.

Abel James: Right.

Dr. Jack: So, the reason why this has stayed so far out of our consciousness is because there’s only in my view two real cultures with a long standing history that have truly lived in the cold a long time and that’s the Sherpas and the Inuits. The difference between two, and this gets to your 80/20 point that I want to bring home. The Inuits prior to 1950 are the ideal culture to study this on. Since 1950 they are not because they eat a warm adapted diet. But, here’s your 80/20 rule, the Sherpas are in the cold because India crashed into Asia and made the Himalayan Mountains. There’s no ocean around them so they can’t eat the diet that is naturally selected for by this ancient pathway. So, they have to rig a diet which predominately is animal protein, but they do eat some other things that are not ideal. But, here’s the cool thing. They have unbelievable findings you know that NASA study. When NASA started finding all this crazy stuff that happened to the astronauts they went to the Sherpas and the Sherpas have some pretty amazing abilities.

Abel James: Super human.

Dr. Jack: Yeah. They are unbelievable what they can do. And the crazy thing is when I started looking into this that’s when I started tying everything together. But, what I found is I believe that there is human performance above the Sherpas and above Lance Armstrong and above my Michael Phelps. Why? Because of what you just asked me about. If you do this 80/20 you’re still going to be way better than what Paleo is or what the standard American diet is or say any elite athlete that’s eating a warm adapted diet. But, I’m saying we don’t know the ceiling because we have never tested it.

Abel James: So, on that point just for the people out there, what are some of the most remarkable things that have happened using this therapy or using these principles either athletically or in your practice because I know that some of those things are pretty freaking amazing?

Dr. Jack: Alright, I’ll give you the couple. We’ll start off with the examples that I use actually in the blog post and actually I used in my book and I used in the TED Talk. The first would be how the modern hominids came upon this information initially. In 1969 we put a guy on the moon. There have been 12 astronauts who have done you know space walks; the first 12. NASA found in all 12 that they all lost weight and the other interesting thing that they found is that when the space modules came back and they counted the food that they generally ate anywhere between 30 and 50% less food than they expected and they couldn’t figure out why. The other thing that they found out is that the astronauts were far more productive when they were in space which also surprised them.

Abel James: Productive how?

Dr. Jack: Productive in terms of the things they were able to do in the time they had allotted. Okay. Because they were doing experiments and everything else when they were up. One of the things that they did when they came back you know NASA collected all this data throughout the 70s, so they started to look for humans on the planet who also were able to do some of these same things and they turned up in the Himalaya Mountains with the Sherpas. Why? The Sherpas are known to be able to do things that the people that are paying them to take them up to Everest just can’t do. For example, they can put 80 to 100 pounds on their frame at 150 pounds and climb all the way up to Everest with no problem. They’re resting metabolic rate is 3 to 500% of those people that are paying them to climb the mountain. So, if Abel went up to the Himalaya Mountains to climb up it would take you three weeks to adapt to the altitude and the cold. It takes a Sherpa three to five days. Okay?

Abel James: Yeah that’s just bonkers.

Dr. Jack: Right and that’s what I’m saying. People need to understand this is not Jack Kruse making this up. This is actually documented in the literature. So, what Jack Kruse has now decided to do is say “How is this possible?” Okay. Then we have the story of Michael Phelps. You know many people have read Phelps’ book and said “Well, what Jack is saying, what Ray is saying, what a lot of people are saying is not in Phelps’ book.” And what I’m telling people is if you think what Phelps put in his book is totally accurate, are you crazy? Because he is still actively competing. Here’s the one thing though that no one can get away from. The dude trains in a cold pool. The whole U.S. Olympic team does this, okay? So, the tie for Phelps and all of the other swimmers is still the cold. Then we look at Lance Armstrong. Same thing. Now that Lance is out of cycling and he’s into the triathlons guess what he’s doing? He’s using cold as part of his regimen. Why? Because he used it to get to where he was. So, now we have the astronauts, we have the elite athletes, then we have the story in 2007 of Kevin Everett who’s the Buffalo Bills NFL player breaks his neck on live TV and is able to walk three or four weeks later. Why? Because the orthopedic surgeon did a couple of interesting things: packed his neck in ice, packed his head in ice, and then infused IV solution into his body that was 32 degrees. Again, not something that most physicians would do. In fact, reading the comments on some of the blog posts, Kurt Harris and Emily Deans would probably have this guys hung up to dry. But, guess what happened? The guy made a remarkable recovery. Well, don’t you think this is happening all at the same time when I’m standing at the foot of Michelangelo’s David and I know all this stuff and you know I know all these little pieces of information. And I’ll give you another one that will blow your mind. We also know and every physician and you know this anyone listening to this podcast is going to know this. When we cut an organ out of the body to transplant, do we pack it in charcoal or do we pack it in ice?

Abel James: That’s a good point.

Dr. Jack: Again, another fact. Then I came upon a TED Talk done by Jessa Gamble who’s a sleep researcher in the Arctic. This one fascinated me because her idea was to dig a hole in the ground in the Arctic, complete pitch black and cold, and put people in it. I don’t know how she got people to do it, but she did. And what did she find when they came out? The slept like rock stars, they lost weight, and they begged her to go back in the hole because they were way more productive than they had ever been. Well, guess what? That was the same story that the NASA astronauts told NASA. So, what’s the tie to all these little stories that I’m telling you? The cold and the dark. So, I’m thinking you know about all this again at the foot of the statue and I realized the way to get into this pathway was circadian biology. So, I kept looking and looking and I found the answer. So, what did I do? I started to I mean who’s the best person to test this on? Here I am 6’2, 357 pounds. I am the perfect candidate to try to find my inner David inside me. So, what did I do? I didn’t tell anybody what I was doing outside of my wife. And I started packing myself in ice and I became the Leptin prescription. The Leptin prescription is a very simple six step process where basically I’m using different macronutrients to confuse my brain using the Vegas nerve as the stimulator. And for those people that don’t understand that, I’ll even make it simpler. Thirty years ago if somebody would have told you that you could take a deaf person that has no ability to hear and I’m not talking about bone deafness. I’m talking about neuro-deafness and you allowed them to hear, they would have thought you were nuts. Guess what?

Abel James: Now they do it.

Dr. Jack: Right. They came up with an electrode that they plant outside the head and it goes into the temporal lobe of the brain and it rewires the brain so we’re able to hear. So, I learned about this when I was a resident in the 1990s. So, I knew that what I learn initially in medical school wasn’t true. We used to believe that the brain was completely you know non dynamic. Once you had it that was pretty much it. Well, that got blown up in the 90s. So, I’m sitting there and I’m thinking you know “I’ve got all this cold stuff. I’ve got all this circadian biology stuff. Why couldn’t I use a stimulator to fix my own brain?” Now, if you know anything about brain surgery you can’t stick a stimulator into the hypothalamus, you’ll die. It’s different than the temporal lobe. But, what I did know is the Vegas nerve wires directly to this area and it’s in my gut and see I can get to my gut. So, I decided I’m going to use timing and big time macronutrients confusion to confuse the brain. I confuse the brain, what does the brain normally do? The brain rewires. When you confuse the brain, its major reaction is to try to figure out the confusion. How did I know that? Well, we have this thing called a Vegal nerve stimulator that we use for seizure patients. Okay? And you put this thing in the Vegas nerve in the neck and it stops seizures. Don’t ask me totally how it works, but it does work. When I started learning about this again as a resident in the 90s, guess one of the side effects that happened from a Vegal nerve stimulator. They lost weight and that’s what gave me this original idea. So, I said you know what I’m going to use my own Vegas nerve with putting a stimulator on me to do this and Abel I’m here to tell you that in 11 months I lost 133 pounds doing this together with the cold thermogenesis. So, people may say that it’s kind of crazy and I’m mad and I’m this and I’m that but it worked. Okay?

Abel James: Where we’re all crazy trying crazy things. Like you know even like fasting is something that people talk about but even a few years ago no one talked about that. And Robb Wolf was talking about that and how in the medical profession if you mentioned that a few years ago then you were nuts and now it’s what everyone is talking about. So, I mean those things just keep changing.

Dr. Jack: And I agree with Robb and you know Robb’s been very measured in his criticism of me and his criticism of a lot of things, but I also think Robb has the foresight to know he doesn’t know really where I’m going but he’s taking a “watch and see” attitude. And I appreciate that from Robb. I also appreciate that from Mark Sisson. I have no problem with people throwing arrows at me. I actually kind of enjoy it because in the end I think they’re all going to realize what the main goal was because if you understand where I’m headed, I’m headed to a point where I’m trying to prove to medicine that we have to stop looking at the last 150 years of randomized controlled trials and instead look to evolutionary biology – 4.5 billion years of what I would call “ultimate proofs” because I think that’s ultimately what’s going to bring our species back from mediocrity. With my theory, the cool part is after I fix me the people that were closest to me were kind of they were floored. I even had this discussion today when we were in surgery with my surgical team and who I just did this last biohack with and they were talking about my son because my son and my nephew were the first two people who I tried the Leptin prescription and the cold thermogenesis out after I did it on me. And my son lost 60 pounds in six weeks and I talked about him in the TED Talk and I showed his before and after picture. And my nephew was 21 years old at the time. He went from 268 pounds to 160 pounds and he’s now working for the government in top secret stuff doing stuff on submarines. And once that happened my patients and my practice started saying “Hey doc, did you have surgery or something?” And I’m like “No.” And they said “Well, can we do what you’re doing?” And then they heard the story about my son and my nephew. And I said “Look, I’ll teach you how to do it. It’s not hard.” And people started having pretty phenomenal results from it. I got the idea from another doctor in my hospital. He’s actually a gastroenterologist. He said “Jack, what you’re doing in the clinic is absolutely astounding.” He goes “You need to stop writing the book and you need to put this on the internet for people to start using” he goes because “You’re not going to have you know an impact publishing this in journal articles because it will take 20 or 30 years for it to get out.” He said “Give it to the people and let them do it.” He said “Because that’s what you’re doing in the clinic.” And you know I had another spark insight. It’s not a bad idea. So, that’s what I started doing and you know the crazy thing about this whole Paleo thing how I came to it is kind of how you did in a bizarre sense. When I came up with this ancient pathway you know theory I realized that evolutionary biology selected the Paleo diet to be the ultimate diet for mammals. Ironically, do you know when I started my experiment I wasn’t eating a total Paleo diet. Not until I had this stroke of insight and I realized why this diet was selected. I can’t go into that too much with you now, but I promise you when Factor X comes out it’s going to be blatantly clear to you why I just said what I said to you. And when I realized that I said you know “There’s a lot of work done on this Paleo diet already.” I already knew about Cordain’s work because I read about it a long time ago. But, when I realized it was the fit for this ancient pathway I said “You know what? What better place for me to drop some of these nuggets than this community.” Little did I know that this community was going to you know tar and feather me because they didn’t like the way I put the message out. And you know I’ve talked to Mark Sisson about this and I’ve even talked to Robb about it. Many people in this community believe that the diet is the ultimate be all and end all, but here’s my point Abel and you know this. You’re a fit guy, but I know you used to be a vegetarian. The internet is littered with hundreds of actually thousands of patients who’ve tried to diet and not gotten good results.

Abel James: That’s true.

Dr. Jack: Why is that? You know and that’s why I want people to start asking questions. I’m going to tell you the reason why. Because the Paleolithic diet is one part of the ancient pathway. It’s very similar to the question you asked me earlier about the 80/20 rule. If you’re doing it, yeah you’re going to get some good results. There’s no question about it. But, you may not be able to fix everything. Like you’re in phenomenal shape so you’re going to be one of those guys that gets good results. Same thing with Robb. Same thing with Mark. Let’s take my type 2 diabetic that’s 350 pounds. He may lose 80 pounds, but is he going to get completely better? Or let’s look at Jimmy Moore. Why hasn’t Jimmy got the results that he totally wants? Well, I’ve got news for you. The reason why is because this pathway requires us to have all the different components in place. And I even used this analogy to somebody today in surgery. I said that if you looked at the movie, I don’t know if you saw it, it was called the Fifth Element. It had to have all of the elements that were present like wind, fire, water, and something else. But, the girl was the fifth element. She had to be in the middle. Ancient pathway works the same way, but if you take my whole theory and boil it down into a funnel, like you take all my blog that are in everybody’s head, you know what the end response is? Eat a Paleolithic diet that is more loaded with seafood, more ketogenic, and do it in a cold environment and make sure you do the cold when it’s called for specifically fall and winter and you won’t believe what happens.

Abel James: So, I have a question about that and I kind of brought this up when we were talking around PaleoFX. Obviously, I live in Austin, Texas and that’s not a cold place even in the winter, so where does that leave people who do live in warmer climates where they wouldn’t be in like below freezing temperatures or normally in a cold spot or even have that option?

Dr. Jack: Well, this is what I would say. Here’s the first thing. Before, and I think people are maybe misunderstanding this because they’ve put words in my mouth. It’s not important so much where you live it’s important what your health is at this point because here’s the key thing. There is still seasonal changes even at the equator. I mean there’s a rainy season and a dry season. So you know, when it’s the rainy season everything is plentiful. There’s a lot of carbs. But when it’s the dry season there’s not a lot of carbohydrates present. In fact, that’s the reason why the animals have to go to the watering hole and get eaten by the crocodiles. You know and people forget that. That even at our equator and the tropics there are circadian signals. Okay? And our biology pays attention to that. All of our nervous systems pay attention to that, but we somehow don’t seem to realize that. What I would say to you in terms of your question, a guy like you, I don’t think you really need to pay attention to it too much because you just need to pay attention to it in the winter and the fall. When you stay blind to that kind of stuff and you don’t test you’re not going to know, but when you test and you know then you have some insight. And I guess my point when I was at PaleoFX was I just wanted some people to say “Look, you know you can call bullshit on Jack Kruse.” You know, I’m cool with that, but just test this out and see if I’m right. Because if I’m wrong you guys can make fun of me and everybody’s usually pretty good at that you know on the internet. But, if I’m right, what have I really done for you? Maybe, just maybe I’ve helped you. Maybe helped you understand that maybe there’s something to this and that we need to start to look at it.

Abel James: Yeah and you know one of the things that I really like about what you’re doing is that like you said it’s the “Fifth Element thing.” You know, my mom is into holistic medicine. So, I was raised in kind of a unique way where there was this holistic approach to life you know. And it wasn’t just nutrition, but that’s a big part. And actually I went up for my speech this past weekend in the northeast and snuck a day to go see my brother who’s an organic farmer and you know it’s New Hampshire so it’s close to freezing, it’s really windy, we’re all bundled up and shivering, but there’s this little cat named Butterscotch following us around all day and it’s just completely comfortable. It was as comfortable inside as out and I’m looking at this little cat and I’m thinking of New Hampshire and I thought of you. I thought of New Hampshire in the summer where it could easily be 95 degrees, 100% humidity and this same little cat is fine and we’re just sweating and miserable the whole time. And I think that’s really interesting because no one really thinks of that as being a problem for us. Right? Because we have heat and we have air conditioning. And you do and that’s what I like about it because just thinking that way we are pansies. We are complete pansies.

Dr. Jack: That’s one of the things that I really enjoyed about you know that round table discussion that we had at the Pendergrass campsite. People actually sat around there and thought about what I was saying about how we have heated Escalade seats and heated houses and we wear clothes that cats, polar bears, monkeys they don’t do. And we somehow think that that is not being counted by our biology. You know, we somehow think that because our brains are so advanced and we figured out ways around this that that is somehow okay with biology. And what I’m saying is that is not a good assumption to make.

Abel James: Right. Anytime we deny nature that’s when we really get into trouble.

Dr. Jack: Right. And you know I think the last group of humans that really had it right was the American Indians and if we go back and look at what they did and what we took away from them, there’s a lesson for us to learn there. I guess my message to people is I want them to just start to think about things. I mean instead of I mean it’s okay if you want to make this about Jack Kruse cause I mean I guess I just don’t get that mindset, but you know I’m not in this for anybody to like me. I’m in this cause I want to save your life and I want to make your life better and I’m just asking people to think. You know, the stuff that I’m asking you to think about actually really isn’t that difficult. The blog posts are difficult for a reason. Because I realize look evolution’s not easy. Not everybody’s going to slug through my blog posts, but there are a lot of people who read my blog that are physicians that are completely they want to know more information. So, I’ve got to provide that. But, when you come down and you talk to me and you know that you’ve talked to me already, I’m a totally different cat in real life than I am on that blog.

Abel James: Yeah, totally. I can vouch for that.

Dr. Jack: I mean and it’s by design. I really you know when I sit down and talk to a patient I want them to really understand. No one cares how much I know. They only care how much you care and you’ve got to when you’re trying to help people in the clinic. When you’re actually a clinician, you know when you’re putting your hands on somebody and you’re operating on them that’s what they’re interested in. They want to know that you’re all in and that you’re there to help them. And I tell people “Look. If I can help you I’m going to help you. If I can’t I’m going to tell you the same thing.” But, there’s very few people who come in my clinic that I can’t help in some fashion. Some of them I don’t even have to operate on. Some of them can help you know just putting them on the right path you know to getting their story squared away.

Abel James: Yeah and even all of these you know people in the paleosphere or blogosphere or world in general who are kind of attacking you right now I think pretty much most of them are outsiders anyway, right? They’re not the status quo and I want to talk a little bit about how you came to this lifestyle because you were pretty much at the top of your game as a neurosurgeon and you made that change. And I think almost everyone would agree with the change that you made and the reasons behind why you’re doing this whether they agree with your protocols or not. So, remind everyone a little bit about what happened there.

Dr. Jack: Well, that was actually I guess you could say that was my opening speech for PaleoFX where I got a little bit personal, but you know in medicine neurosurgery is pretty much at the top and it’s probably the toughest specialty to get into. It requires a lot of personal sacrifice. Like I gave up the decade of my 20’s and most of my 30’s to train to become what I became. And I guess what happened to me at the foot of that statue is I got away from that for 11 years. I got away from the person that I was as kid because of my training. I allowed my profession and my specialty to do a lot of thinking for me cause of the way they trained me. You know, they trained us the way to think.

Abel James: Or the way not to think, right? In some cases.

Dr. Jack: Right. It’s actually right both ways. To train me to think like a neurosurgeon, think very reductively, to think six steps ahead of where most other people think. That’s actually how people always ask me “What’s the difference between a neurosurgeon and say a psychiatrist or a radiologist?” It’s simple. We think six steps ahead of everybody else. Why? Because in brain surgery if you make one mistake it’s magnified tremendously and you don’t have the margin of error like you do when you do general surgery. You know everything is very small, very microscopic, and you know if you suck the wrong thing out you could have just removed 3rd grade. You know it’s gone and you just get this sense when you’re training that neurosurgery is a little bit different. And I hate to say it, but it does change our personalities too. And I will tell you from the time I finished my training up until about 2006 I let that get away from me. And you know I told you guys at PaleoFX about a patient who came to me early in my residency who really brought that point home that I lost. And you know it pains me to admit this, but she taught me a lot about what being a great doctor is all about and I completely forgot her message for 11 years. But, I remembered her message. You know, but in 2006 and if you asked me what really put me back on track was thinking about her and then thinking about all these things that I’ve been blogging about. And I have to say that the thing that really brought it home for me and I guess it’s why PaleoFX was probably really special, one of the guys that’s a Special Forces guy that you met at PaleoFX shared with us something on Facebook that just really caught me off guard. And the night before PaleoFX I just decided to go back to what that patient had taught me and just say it and just put it out there for people cause I think when I said it you know a lot of people had never met me before and I think they had a lot of preconceived notions of kind of what I was and I think what I gave them that day is that I’m not what they think I am. What changed in me in 2006 is that I decided to become the doctor that I should have become in my entire career. In fact, I’ll give it to you a better way. I’m sitting here looking out at the lake and thinking of it. I was a good doctor. I was at the top of my profession, but I decided that I didn’t want to be good anymore. I wanted to be great and to be great I had to reject good. I had to erase everything about me that was good to become great. I had to in essence empty my cup so that I could fill it with greatness. And to me to be great as a physician, and I don’t care what kind of physician you are, you have to have total care about the person that’s sitting in front of you that you’re taking care of. You have to realize that everybody comes to us with different problems and I can’t solve everyone’s problem. I mean I know that. You know that. The listeners know that. But, what they do expect from me is for me to give them my very best.

Abel James: Yeah.

Dr. Jack: And up until 2006 I wasn’t giving my very best because I wasn’t telling people how to eat and I was no good example for them. All you had to do was look at me. I was a complete fat ass. And I said you know in order for me to change the culture of medicine, I have to first change the culture of Jack Kruse. And that’s what I did; changed me. I became the change that I wanted to see in my profession. And I guess what you would say is that every day since 2006 until today I’m still improving my former self and I’m now translating that into you know touching other people. Kind of like when you, me, and Alyson met you got that sense from me. That’s kind of really how I roll now. I think people understand that’s me and I may not get that from the blog. I get that 100%, but that’s really how I think and feel. And I have to tell you what happened on January 9th that was pretty hard for me to do. It was also hard for me to do because I did it lone wolf and I could even tell the people even that cared about me the most even why I was doing it because I knew if I did they’d try to stop me.

Abel James: Yeah, so I did want to talk about that. When you started ignoring the body of past research that’s out there, you started doing your own personal like Jack Kruse science. Like walk me through that process. What does that look like in terms of what’s Jack Kruse’s scientific method?

Dr. Jack: Well, it’s kind of funny cause we talked about it earlier. You know what had a huge impact on me when that article came out in the Atlantic Magazine I think it’s called “Science Lies.” And I mentioned it in one of my blog posts very early on, I read it and I was like “You know what this guy’s basically saying? He’s saying that basically everything I spent hours learning in the library as a medical student, as a resident is total horse shit.” And it struck me that if that’s the case then that means that a lot of the dogma that I believe is also total horse shit. So then I started to look really hard at some things that I thought were incongruent in my own specialty and I found a lot. Then I started to look in other branches of medicine and started to find a real lot. And the one that really hit home for me was some of the work on you know cardiovascular disease and cholesterol and you know that tied immediately into what I had already discovered myself about the Paleolithic diet and the ancient pathway and you know Cordain’s work and I started to see ties. And you know all these ties, instead of think reductively like a scientist or a physician would, I started to think with that child brain that thinks you know horizontally and the more I thought horizontally the more creative I got, the more I started to see that things that didn’t seem to be tied together actually were tied together. So, the more I thought like that the more I said “You know I’ve got to start testing some of this stuff on myself.” So, I became like the ultimate biohacker and the more incongruities that I found the more things I questioned. It got so bad that pretty much I started to realize probably around 2009 that pretty much most of the things that I learned were not totally true. And that’s why I come up with my famous saying. Most of the people on my own blog forum and the people that know me best, I’m talking about personal friends, know in fact it’s even on my iPhone, my wallpaper, it’s a graffiti from a New York City subway that says “Question everything.”

Abel James: I like that.

Dr. Jack: That’s what’s on my cellphone. That’s how I live. You know I don’t know if people read the blog or know me know that that’s true about me, but I think the people who personally know me the best know that I question everything. Anything. I’m a skeptic right off the bat and then I go do my own homework and I start thinking about it. And I tell everybody. Anything that I post, I want you to hold me to the same standard that I hold you to.

Abel James: Yeah, totally. It’s funny because I used to work on some of those research projects and what was so shocking to me was how the sausage was made so to speak cause I guess when you read something, especially a scientific paper, you assume that everything is 100% clean and perfect. And when you’re actually writing them and you look at the data and you look at the statistics it is incredible the amount of things that you could make it say in the conclusion you know or in the discussion piece of the paper.

Dr. Jack: You’re totally spot on. And I’ll tell you the other thing that really infuriates me and I am going to pick on the blogosphere right now. They make the assumption that when Stephen Guyenet or when Paul Jaminet say something it’s the gospel and I’ve got some bad news for you. There’s a lot of things that I’ve seen that I just sit back and go “Oh, if they only knew.” It’s just not true. You know and here’s I guess the hard point for humans I guess and I think this is socialization. Just because one or two things aren’t true doesn’t disqualify you know that person’s opinion or what they’re actually saying in the bulk of the paper. You know I think that’s one of the problems that people have with me. If they find some incongruity or something that’s a problem well then you know what? “He’s just a total asshole.” And that’s just the way it is because he’s an arrogant neurosurgeon. And I’m cool with it because I get where it comes from cause let’s face it, Abel you know that a lot of people are pissed off at my professional. You know I get it loud and clear. I understand why. But, what I guess they don’t realize is that we’re all on the same team. I’m on your team and I’m on their team. Even when Emily Deans and Kurt Harris you know are screaming at me look I’m cool with that. You know why? Cause we’re just like brothers that hate each other.

Abel James: Yeah. I’m going to have to check that out.

Dr. Jack: We are. We’re still on the same team and I’m trying to get them more engaged so that they start doing things to help people and Paleo. You know it’s not good enough to eat Paleo and write about papers. We need them to start helping people and answering blog comments and helping the thousands of people out there that need their help because you know these are two enlightened physicians. And we need them. You know we need them badly.

Abel James: Yeah you know we all need each other. I think you’re right. We are on the same team. And this reminds me of what we were just talking about. About in my consulting work back in the day we used to have this thing called “being directionally accurate.” And so you know it’s just like there’s 100, there’s negative 100, and there’s 0 and if it’s 2 and you’re right, the data says that it’s 2, then it’s directionally accurate and that’s all that really matters you know.

Dr. Jack: You know I love that point. I’m going to have to use that in a blog post because you know what? I guess I’m going to have to start saying “I think Jack Kruse is directionally accurate.” And I’m going to tell you why I say that. I think when Factor X comes out I want you to remember this point in the blog post when you first read it because I will tell you that when I first came up with it that it made me realize so many different things that we incongruent in biology, chemistry, and biochemistry that all of a sudden made complete sense. You know it was like all the foggy parts for me as a neurosurgeon made ultimate sense right away and I just sat back in my chair and it absolutely stunned me.

Abel James: When are you releasing it?

Dr. Jack: Well, right now I’m contemplating two things. I told Jimmy Moore, Gary Toms backed out of the low carb cruise.

Abel James: Oh really?

Dr. Jack: Yeah he did and Jimmy wants me to be the opening speaker. I may do it there although I don’t know how many of Jimmy’s followers read my blog. Probably not too many of them. I don’t know if I’m going to do it there. But, I came up with another idea cause a patient yesterday in my clinic said “Hey doc, why don’t you just do a private chat room and you know release it for an hour and let people read it, but don’t give them any of the details?” Because I will tell you even when I tell you what it is you will definitely be intrigued, but you’ll want to know how I got there because how I got there dude was probably the greatest story of my life.

Abel James: Stop holding it back then.

Dr. Jack: Well, you have to realize this it’s so hard Abel to just spit it out because when you spit it out it’s just too much to take in and I need to explain it and put it in context. And if you were in front of me like you are right now, I could tell you literally in five minutes you’d get it but that’s because you and I have context together. You know we’ve talked and you’ve kind of have an idea about where I’m headed.

Abel James: Where you’re coming from.

Dr. Jack: No and I will tell you this. I shouldn’t tell you this, but I’m gonna. At our Pendergrass compound there who I was moved to tell and when I told them I wish you could have seen his face. Kevin Catrell also knows and I told him at my house and he was also like “Jack do you realize that no one’s going to realize where you’re going and this is why I think Robb Wolf eventually is going to be very happy with where I’m headed because I am looking for an espistomologic foundation for biology. That’s what medicine’s missing. You know physics has it and quantum mechanics. Chemistry has it in the same place, but we don’t have it for modern healthcare and it’s the reason why there’s so many incongruities with what I do daily and what my colleagues do daily and the crap that we read in journals. And I think when we start to use evolutionary medicine in biology as our North Star, I think things are going to change for patients. And if you ask me what have I found you know since my all my three biohacks that I did I will tell you that’s what separates me from a lot of people now because I use those things now as my North Star, as my Rosetta Stone for how I practice medicine.

Abel James: Yeah and that makes you rare at this point which is very strange to me, but I think that that’s all changing. I certainly hope it is.

Dr. Jack: I think you’re right. I think it is. I think I guess the way that people perceive me publically and through the blog and how they perceive me when they meet me is probably the rate limiting factor and I think that will change over time. You know I make a great effort and you know the reason why to answer all the questions on my blog because I feel it’s my duty to do so. And those people out there need my help. If I can help them I’ll help them. If I don’t know the answer I tell people “Look I don’t know the answer to this, but if I come across it I promise you I will let you know.” And I do what I can. There’s only 24 hours in a day. You know I’m a busy dude. I have a clinic to run. I have a lot of outside interests, but right now I’ve been really focusing in on the blog and the comments and you know doing my own biohacks you know and helping people that need my help and if I can do that I feel like you know I’ve improved myself as a physician from where I was in 2006 and you know I feel like I have a debt to humanity that I have to make up for those 11 year where I kinda lost my way in conventional wisdom.

Abel James: Yeah and I was just thinking back on that in terms of being directionally accurate looking at just you. Looking at your weight loss and what happened there just inexplicably to everyone else. So, if you’re going to ask if that’s directionally accurate I would say yes you know.

Dr. Jack: No you’re right.

Abel James: At least you’ve got something right. I would imagine that you have a heck of a lot right if those are your results. And it’s not just you. Like you said, it’s a lot of people have had great success with it.

Dr. Jack: Yeah. I mean I think the blog comments are pretty much you know proof of that. I mean look there’s not everybody is going to get lit on fire by Jack Kruse’s Leptin prescription or cold thermogenesis. But, here’s the ironic thing. There’s a lot of people that are. So, I think that you or at least I would think that some of the more critical people out there would say “Hey, if this is working for some people why is that?” You know and “Let’s take a look at that.” And then to know that we have these examples of humans that have these extraordinary abilities that we can’t explain by warm adapted biochemistry that’s in the book that Mat Lalonde is an expert on. Well, how about we take a look at that? Let’s sit down and have that “Come to Jesus moment” and say “Why is this?” Some people like Skylar Tanner recently said “A guy like Wim Hof is genetically gifted.” Sorry, that’s not how it works brother. And the reason why is because Wim Hof isn’t the only guy that has this. There’s guys that are completely unrelated to him that have this. The one common tie to everybody that has these abilities ironically is the cold. And that’s kind of where Jack Kruse is headed. See that’s for me the road to optimal definitely includes the cold and I will tell you that the cold is directionally tied to Factor X. That I will guarantee you and when I show you exactly how it is directionally accurate as you put it, I think it’s going to give everybody pause to think “Hmmm. So this makes sense. This is why epigenetics sped up.” Because in the pure cold you know biochemical reactions slow down. So, how would Mother Nature react? It would speed up epigenetics. Now, do we have to know like all the details and all of the papers like some of the people in the Paleosphere want? No. Because you know what we know? This is in fact occurred. And you know how we know it’s occurred? Because we came from ancestors that are very unlike us. That’s why. And just think about that. We are the proof of concept.

Abel James: That’s interesting.

Dr. Jack: You’ve got the reason. Okay? I’m going to show you the reason why and when you understand and I can promise you Factor X is something that you learned in 3rd grade. Okay? When you hear what it is and then you tie it to this huge framework that you’ve developed as a very smart young man you’re going to say “Wow. This kind of makes tons of sense now. This kind of explains why there’s not a lot of hominid skeletons. This explains you know why it’s been our blind spot. It also explains why our development has occurred. It also explains why you know we have all the circadian mismatches. You know it’s also why you know Steve Jobs died at the hands of what he put in his body and also all the light that he was using at the wrong times. You know it all starts to fall into place and I wouldn’t call it a theory of everything. I like your term. I’m going to use it that. It is directionally perfect. You know I mean I’ve thought about this for six and a half years Abel and I’ve looked for incongruities in it. I can’t find any.

Abel James: Yeah. I did want to ask you about this. So, obviously there’s a benefit to cold adaptation. Now, is there benefit to adaptation to the heat or is that somehow detrimental or what does that look like?

Dr. Jack: Well, I think if you ask me the question, I think we evolve to a warm environment meaning that I think the Leptin receptor primordial condition is cold. In fact, I’ve said this on the blog. In CT one I made the comment that all life starts in cold. It started in the bottom of the deep, cold ocean. So, I think what happened is I also say that sleep is the primordial condition for that same reason. So, I think what happened as evolution as time evolved evolution sped up. We evolved into a warmer climate. So, we can adapt to the warm. Here’s the reason I say that. Most people are completely unaware of this biologic fact. 90% of the biome on this plant is cold adapted as we speak today on April 4th. We are part of the 10% that’s not, yet we somehow think that our 10% is better than the 90% that’s out there.

Abel James: Yeah.

Dr. Jack: In fact all life forms until you know millions of years ago were all cold adapted. You know we still have tons of cold adapted. Look there is an article that came out that I just read that came out two weeks ago. They found a fish in the bottom of the ocean up in the North Pole that they believe is 10,000 years old. That sounds completely psychotic. Okay. But guess what? Using this ancient pathway, it’s not psychotic at all. In fact, it makes a ton of sense because aging is going to slow down in the cold. Well, if that thing freaking lives on our planet that means evolution has a plan for this. That means that we need to understand what that plan is.

Abel James: Yeah.

Dr. Jack: Because guess what? The remnants of that plan are somehow built into us even if we don’t use it or not today. And that’s the point that I’m trying to make to people that I’m telling you that Mother Nature built something into us that we are completely blind to that we can use if we understand how to use it. I think that the way that we live today, we evolved into this environment via natural selection. So, yeah I think you can eat bananas. I think you can eat grains. I think we can do a lot of things. You know made Matt Lalonde that point in ancestral one last year and people misunderstood it. There’s many things that show up in evolution that are good for us. You know that actually lead to expansions, but I’m taking a way bigger view of it than that. I’m saying there’s things built into us that provide ultimate survivability and that if we live in that pathway more than we don’t we get benefits from it. That’s what I’m saying and of course yeah life can live on the equator. You have to be a moron not to know that. But is it, I guess the question you really asked me is “Is it optimal or is it suboptimal?” I guess that depends on your perspective. I think you know my answer is it’s suboptimal.

Abel James: Right. You know it’s funny. I was just and talking about the cold slowing everything down kind of reminds me of this. When I was up in New Hampshire I went outside and obviously it’s the beginning of April and it’s cold, but I heard some frogs. But, when I walked outside it was nighttime and it was chilly and I couldn’t like understand what I was hearing. I grew up in New Hampshire. I know what frogs sound like and these did not sound like frogs because it was so cold and it was right on the brink of them not being able to move or even vocalize. And that just reminded me too of how much everything kind of slows down in the cold and man growing up in New Hampshire I can definitely vouch for that. Three hours of sunlight.

Dr. Jack: Yeah, I’ve been in New Hampshire in the cold and I’ve been in New England. And I know what you’re saying. There’s even you know it’s funny. You’re going to laugh when you read the final chapter of my book because guess what I talk about? Canadian frogs are part of how I figured out Factor X. They’re actually in the book. People don’t know this, but do you know that insulin resistant in those frogs are actually a way for them to make antifreeze in their blood so they don’t freeze?

Abel James: That doesn’t surprise me.

Dr. Jack: Yeah. Biology has plans for everything, but humans just don’t seem to be aware of a lot of this stuff. And I think when you become aware of all these little facts and you start thinking horizontally and tying them all together, you start to get this really great picture painted in your head saying “Wow. Mother Nature is incredible.” I mean she is absolutely incredible. The complexity that she figures out, you give her the worst possible scenario and she has a solution.

Abel James: Wasn’t there a quote from Jurassic Park? I think it was “Nature always finds a way.” Frogs are involved with that too I think.

Dr. Jack: Well, you know what? Abel I have to be honest with you. My CT six blog post, that’s exactly what I’m saying to people. That pathway is in us and it’s in us because nature had a way. There’s an evolutionary bottleneck that we faced that selected for that pathway. And personally, I’ll even take it a step further. I think that pathway was built into us all the way from the beginning of when life formed. And I absolutely believe that and I’ll lay it out for you at some point down the road. But, I think once you understand Factor X you’ll understand why I say that because like I said that’s why so many people are fascinated by what’s going on, on the moon of Saturn called “Titan.” You know it’s basically a frozen giant that’s a giant ocean that’s got a volcano spewing out water vapor you know and it’s solid frozen and physicists believe that there’s probably life in the bottom of that ocean. Well guess what? That’s probably exactly what the earth looked like four billion years ago.

Abel James: Isn’t that crazy?

Dr. Jack: It is. It’s huge. And you know the cool thing is it’s kind of like looking at Einstein’s theory of relativity. It’s kind of like a black hole back to our past. You know if we can get there and examine what’s going on at that planet we can get some more insight. I guess what I’m saying is maybe I got a little bit of that same insight standing at the foot of Michelangelo’s statue and coming up with the ancient pathway. I just want people to examine this and let’s try to figure out why Wim Hoff, and me, and some other people can do some of the stuff that we do because based on the stuff that’s in the biology book that I learned in biochemistry, it’s not possible. And you know for me to be able to do some of the things that I’ve done, for Wim to be able to do some of the things that he’s done, for Phelps to do what he did, for the astronauts to do what they did, you know for a heart surgeon to transplant a heart, or how about this one. We didn’t talk about this one yet, but this is a huge one. NASA took the technology that they learned about from the astronauts and they just licensed it to a company called Vasper in California and guess what it does? It’s an exercise bicycle that puts cold pads all over your body and uses compression. You know stockings on your arms and your legs to increase lactic acid. Guess what it does?

Abel James: Accelerates results I would assume.

Dr. Jack: You do 20 minutes of exercise and it equals two hours of exercise in terms of calories burned. Well guess what? If you look at the Vasper technology and you open up a textbook that Mat Lalonde is an absolute stud expert at there’s nowhere to show where Vasper works, but yet it works. So, this is what I say to everyone in the Paleosphere. You can call bullshit on me, but we need to figure out how in fact this thing works because what I’m telling you is the answer is not in the medical literature right now. It’s not. And for you to deny that this is here on planet earth right now is absolute lunacy because it’s here. It’s time for us to start to look for the answer. I guess what I’m doing is knocking on that door.

Abel James: I think it’s pretty cool stuff and we’re coming up on time here Jack, but before we got is there anything else that you want to talk about?

Dr. Jack: I think you’ve kind of hit me in a lot of good places. You know I just would hope that people would give me a little bit more leeway to try cold thermogenesis for themselves. Do it for 30 to 60 days. If it doesn’t give you any benefits that’s great you can come on my blog and tell me I’m an idiot. I’m fine with that. I’ll post your comment. But, you know if it works do me a favor. Also post a comment so that other people that are on the road to optimal that I’m trying to light that path for we can help because you know we are all in this together. And as I told you when I first met you Abel, you know the light of our candle that is our bright light inside doesn’t diminish when we light other candles and I guess what I’m trying to do is I’m trying to light that path to optimal for the millions of other people that are eating a standard American diet behind us that are train wrecks. You know I don’t have to save you know people like you, your girlfriend, Robb, Mat Lalonde, you know Kurt Harris or anybody else. They already get it. Our job since we get it is to help the people behind us that are clueless.

Abel James: I love that. I think that’s a great message.

Dr. Jack: Well it’s true.

Abel James: It’s totally true.

Dr. Jack: It’s true and I just wish we could put all the bitterness and the one-upmanship you know I don’t care you know who gets credit for what. It doesn’t matter to me. You know what lights me on fire is when a patient comes in and tells me “Dr. Kruse, I am now better than I was when I first met you.” Dude, that’s all it means to me. That’s the coolest part. That’s what my job is all about.

Abel James: There are a lot of thing going wrong right now especially the way that conventional and standard America kind of lurches along and I think we’re all trying to upset that right now and that’s commendable in whatever way that you do it. I think it’s commendable.

Dr. Jack: I agree with you. I mean I couldn’t agree more you know and that’s why coming on and doing Podcast with guys like you and you know I mean here’s the cool thing. Look at you and I met at PaleoFX. If PaleoFX didn’t exist this Podcast would never happen.

Abel James: True.

Dr. Jack: And we would not have share these ideas that we’re sharing today and people may not have gotten your message and may not have heard some of the things that I said and you know I think it’s important. I think it’s important that we all share each other’s ideas because any time that I sit down with anyone like when I sat down with Allison you know your girlfriend and talked to her, I got some insights from her that I would have never got if I didn’t go to PaleoFX. The same thing with all the people that I sat down with. Even if I sat down with them for 30 seconds I took a piece of them away with me and they made me think about things differently if I didn’t come in contact with them.

Abel James: Yeah. It was an awesome conference.

Dr. Jack: It’s phenomenal. I think it was one of the best conferences that I’ve ever been to. And the people that I met there, I can’t wait for people to see the videos.

Abel James: Yeah. Pretty much all the presentations that I went to there were amazing. It was good stuff.

Dr. Jack: Yeah I agree. I wish the one thing that we would have done differently is that we would have actually had if we had big panels it would have been cool for the panelists to discuss or ask each other questions.

Abel James: Yeah you’re right.

Dr. Jack: One of the things that really kind of concerned me. I didn’t have much time and I’ve never really sat down and spoken to Paul Jaminet a lot, or Emily Deans a lot, or Chris Kresser a lot. Part of it is I don’t think they get me. But, at the same time I respect each one of them in their own way and I think it would have been really cool for us to sit down and ask each other questions. Maybe we could have probed each other’s minds about really how we think and not how we perceive each other and how we think. Cause I think people would have gotten a lot out of that.

Abel James: Yeah. That’s a good point. Well, we’re all going to be at AHS right?

Dr. Jack: Yeah. Right now I’m planning on going unless the paleosphere votes me off the tribe.

Abel James: I don’t think that will happen Jack.

Dr. Jack: Who knows.

Abel James: But, Allison. I was thinking about you. Allison and I were out the other night and you’ll be happy to hear that we went to Fogo de Chao and had a great time.

Dr. Jack: There you go.

Abel James: But, I did want to ask you. You’re a wine guy and I’m still a young buck with a lot to learn. What’s a wine that I actually put on my list?

Dr. Jack: Alright. Well I’m not going to give you a wine. I may give you a list offline that I can give you, but this is what I will tell you for the Podcast. The wines that are highest in resveratrol are Argentine Malbecs. Why? Because they grow high up on the Andes Mountains where the sunlight stresses the grape skins. The other one would be French Pinot Noirs.

Abel James: I love those.

Dr. Jack: Other places would be Long Islands, white wines because the climate there is very much like New Hampshire. Also, the white wines of Quebec up where Mitch Baird and you know the Inuits are located for the same reasons. Now, not the insulin sweet wines. You’ve got to stay away from those. Those are the wines that you drink in the summer time when Paul Jaminet says starches are safe. But you know the ironic thing of this whole thing if you were to ask me what is my all time favorite wine and this is the true irony. You know that I’m always on Paul Jaminet’s case about safe starches. I love Chateau de Kemp. It’s what they call Golden Rod. It’s the sweetest wine on the planet. It’s the best wine ever made by humans and I have a huge collection of it and I can’t drink it.

Abel James: Well, that’s what cheat day is for.

Dr. Jack: Alright. Well listen. I don’t have a cheat day. I don’t. And I’m going to tell you when I actually put the weight on to have the surgery I pounded a whole bottle of De Kemp. I’m not kidding you. It was the most glorious thing that I’ve probably done in the last six years because I have to be honest with you. I’ve only drank De Kemp in probably three or four times in the last six and a half years. And this wine, for anyone who has not had it, it is absolutely unbelievable. It is something that you must try before you die. It’s kind of like going to Mardi Gras before you die. It’s just something you need to do once. It’s just phenomenal. It’s great wine.

Abel James: Awesome. Alright, we’re up on time here but thanks so much Jack. This has been awesome.

Dr. Jack: Alright Abel. It was great talking with you and anytime in the future.

Abel James: Right on.

Dr. Jack: Take care.

Abel James: Jack certainly speaks his mind doesn’t he? Well, that’s what I like about him. Alright, well thanks so much for listening and before you go I would really appreciate it if you could leave a positive review on iTunes. It really helps in the rankings and all your support is very much appreciated. You can look for me at and you can check out Jack’s blog at And with that, until next week. I have tons of really awesome guests coming up, so stay tuned. Cheers.

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  1. Cold Thermogenesis works.
    I used to breathe in cold air gradually, from Autumn into the dead of winter to halt bacteria and alleviate virus infections from flu; dreaded taking ice cold baths; was a very sickly child with malnutrition. Upon migrating to England, I coupled cold air with exercise, food and rest. My body radiated heat in the midst of winter whereas my English counterparts wearing heavy clothes would shiver. At university, they were amazed and shocked that I could move about at low temperatures with wind chill with a T-Shirt and Jeans. However, fingers froze up with exam writing. Adapted to -20 Celcuis when I recovered from a 45 degrees celcius fever in USSR. My drawback was returning to the humid tropics where my body continued to get easily over heated. I still duck for air-conditioning or the refrigerator to cool down and reduce effects of humidity. Along with it, all the ailments, eczema, hives, asthma, sinus, allergies, slowly begin to creep in. Switched to Quercetin in lieu of pine bark, as antihistamine from Zertec, clarityn. Processed milk products, asprin, cows, goat, etc. causes anaphalactic shock. Natural milk does not cause allergy nor anaphalaysis. Pardon the spelling errors.

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