Episode 10 – Stephan Guyenet on Food Reward and Weight Loss

This week we’re happy to have Stephan Guyenet from Whole Health Source back to discuss the body fat set point and food reward theories of obesity and weight regulation.

Questions covered include:

• How does the food reward system work? Why did it evolve?
• Why do certain flavors we don’t initially like become appealing over time?
• How does industrially processed food affect the food reward system?
• What’s the most effective diet used to make rats obese in a research setting? What does this tell us about human diet and weight regulation?
• Do we know why highly rewarding food increases the set point in some people but not in others?
• How does the food reward theory explain the effectiveness of popular fat loss diets?
• Does the food reward theory tell us anything about why traditional cultures are generally lean?
• What does this all mean from a practical perspective? How can these theories be applied to regulate weight and improve metabolism?

Click here to read all of Stephan’s recent posts on the food reward concept.

Full Text Transcript

Danny Roddy: Hello everyone and welcome to the Healthy Skeptic podcast. My name is Danny Roddy, and with me is Chris Kresser, health detective and creator of TheHealthySkeptic.org. A blog challenging mainstream myths about nutrition and health.

Chris, how are you doing buddy?

Chris Kresser: I’m great Danny, how are you?

Danny Roddy: I’m very good.

Chris Kresser: I’m super excited to have Stephan Guyenet here. I kicked off my podcast way back in whenever that was―I don’t know. 2009. First episode was Stephan. We talked about obesity and weight regulation. And he’s back to share some of his newest research and really fascinating new theory about obesity and weight regulation. We’re going to talk to him about that.

For those of you that don’t know Stephan he’s―has a bachelors in science and biochemistry from the University of Virginia. And a Ph.D. in neurobiology from university of Washington. And he studies professionally the neurobiology of body fat regulation. And in his spare time he studies and conveys time tested strategies for achieving and maintaining health and well being.

Which I love the way he wrote that. And he writes about this on his blog. WholeHealthSource.BlogSpot.com which if you don’t know about, you absolutely should. It’s one of my favorite blogs. I―Stephan, and I’ve learned a lot from him over the years. On everything from cardiovascular disease to metabolism to nutrition and I’m just really excited to have him on the show.

How’re you doing Stephan?

Stephan Guyenet: I’m great, nice to be here Chris and Danny.

Chris Kresser: So we’re going to just do a really short review of the first podcast that I did with Stephan. Literally like a few bullet points of what we covered. I really recommend you go back and listen to it if you haven’t listened to it yet, because some of the things that we’re going to be talking about today are a little bit more advanced. Maybe if that first podcast was the 101 class, this is the―you know―the advanced seminar.

So in that first podcast we talked about why the common weight loss advice to eat less and exercise more isn’t typically effective. We talked the long term results of various weight loss diets―low carb and low fat. And I’ll give you a hint; they’re usually not very good. We talked about the body fat set point and its relevance to weight regulation and that’s going to be a big focus of this show today. We talked about the importance of gut flora. And gut health in general in weight regulation. We talked about the role of industrial seed oils in the obesity epidemic. And discussed obesity as an immunological and inflammatory disease, which I’ve written about quite a lot recently on my blog.

And of course we talked about some strategies for preventing weight gain and promoting weight loss, which is going to be another focus of the show today. So, you know, if I had to summarize all that from the first podcast it would be that―exercise doesn’t typically work for weight loss. Low fat and low carb diets might work in the short terms but over the long term aren’t universally effective.

And, would you say that’s an accurate summary Stephan?

Stephan Guyenet: Yeah, it is. I mean you can put people on low fat or low carb diets. And actually I’ve been recently looking into more detail on the literature on low fat diets rather than low carb, and comparing the two.

Chris Kresser: Blasphemy!

Stephan Guyenet: I know, I know. Kind of a new interest of mine. But anyway, it’s actually―the two types of studies are remarkably similar if you really look at it. They―When you put someone on a either a low carb or a low fat diet, even if you don’t tell them anything about calorie intake. You don’t say anything about reducing calories. They will spontaneously reduce their calorie intake and lose a certain amount of weight.

And that weight loss―if they maintain their diet changes it’s somewhat durable, but it’s fairly modest. So typically in the range of three to five pounds over the course of a year or two of weight loss. So yeah, as you said―it’s not ineffective, but it’s relatively modest when you average it across people. That being said there are some individuals who respond relatively well to low carbohydrate or low fat and can lose and maintain a large amount of fat loss.

Chris Kresser: Right, maybe we’ll get a chance to talk a little bit about what that individual variation might be about. I think my―you know, there haven’t been a lot of studies on this, but my theory is that a paleo-diet is probably more effective then low carb or low fat because it eliminates some of the food toxins, or at least dramatically reduces them like industrial seed oils.

But even having said that, I still see plenty of patients in my practice everyday that started to lose weight on paleo diet but then they plateau or even start to gain weight again. So I’m sure a number of those folks and other people out in the blogosphere are excited to listen to this to see if they can get some ideas for how they might―you know―continue making progress.

So before we get into this new series you’ve been writing on your blog and your new theories. Can you just briefly introduce the concept of body fat set point to people who might not be familiar with it, and its relevance to weight regulation?

Stephan Guyenet: Yeah, so it’s been known for at least half a century that when you perturb the body fat level of animals and humans by manipulating the amount of energy that they’re taking in or the amount of energy that they’re expending. They will act to bring fat mass back to its former level. So a simpler way of saying that is that fat mass―that the body attempts to keep fat mass constant by influencing the energy entering the body, the energy exiting the body. And the―where that energy in the body is directed―towards fat mass or towards lean mass. So the reason that’s important is that it has implications for efforts to lose fat and to maintain leanness.

Because if you’re trying to lose fat by just eating pure calories or by just exercising, you’re not necessarily―you’re basically going to be fighting your body, which is going to try to maintain the amount of fat that you started off with. And that’s why that type of strategy is usually not very effective. And people who achieve and maintain fat loss usually don’t do it by keeping their diet exactly the same, but just eating less of it. They usually do it by changes in diet quality. Which we’ll discuss somewhat later.

Chris Kresser: Right, so it’s not just mind over matter and a matter―you know―and will power that comes into it. But the brain is literally―you know―controlling the body fat set point and the determining what weight it thinks we should be at.

Stephan Guyenet: Yeah, and ultimately you do have conscious control over the amount of food that goes in your mouth and the amount of exercise you do. And that obviously can influence body fatness. But the problem is that, if you’re doing what your body―if you’re basically fighting your body on that, it’s going to be very difficult and it’s going to require a level of sustained discipline that most people don’t possess.

Chris Kresser: Right.

Stephan Guyenet: So a better way and probably actually a healthier way is to work with your body and change that suspended level of fat mass instead of trying to fight the level of defended fat mass.

Chris Kresser: Right. Okay, so we know there’s a body fat set point that regulates weight. And we know that this set point for some reason goes awry in certain individuals. So what are mechanisms―the major mechanisms Stephan, that make that happen?

Stephan Guyenet: Yeah, so let me explain a little bit more about what the system actually is before I talk about the mechanism. The dominant element of this system is a negative―it’s called a negative feedback loop, between fat tissue and the brain. So what that means is that fat tissue produces a hormone called leptin that―the more fat you have, the more leptin it produces. Leptin goes to the brain and basically increases energy expenditure and decreases behaviors related to eating food. So it decreases hunger. Decreases motivation for acquisition of food, etc. So it’s basically a feedback loop where the more fat you have, the more of a stimulus there’s going to be reduce that fat mass. So it tends to settle in at a balance of at a specific amount of fat mass.

And for a lean person that balance is a relatively low level. For an obese person, the balance is a high level.

Chris Kresser: Right.

Stephan Guyenet: So, how does it go from being balanced at a lean level to being balanced at an obese level? So I believe there are two factors. And one of them is basically an interference with that feedback loop that I was just talking about. Where basically the brain becomes less sensitive to that leptin signal. So, the less it hears the leptin signal, the more leptin there’s going to have to be to get the same amount of signal, so the brain feels satisfied.

Chris Kresser: Right.

Stephan Guyenet: And that means that you need more fat mass to produce that same amount of signal. So the system will settle at a higher fat mass. So, it’s known that one of the factors―I mean, I will say that―you know―there’s still a lot of unknowns here. It’s known that inflammation in the hypothalamus can suppress that signaling via a variety of mechanisms. So basically interference with that system itself possibly by inflammation, possibly by other mechanisms is one way of doing that. Another way of doing that I’ve come to appreciate only recently is changes in the palatability and reward value of the diet.

So basically, there are these interconnections between the circuits that regulate body fat levels and regulate the response to rewarding food. That is, food that you find tasty, palatable―in certain ways. Those systems are interconnected and they actually influence one another. So for example, if you’re really, really full and you just had really big meals over the last three days, you’re not going to be very interested in eating more food. Whereas if you hadn’t done that―or let’s say, you didn’t eat anything for three days, you’re going to be very, very interested in eating more food.

Danny Roddy: Sure, Right.

Stephan Guyenet: That’s basically that homeostasis system―system that tries to keep fat mass in balance interacting with your food reward system which is what motivates you to eat food. And there is also reciprocal regulation that’s happening from reward pathways to the body fat homeostasis system. And that’s what I think. And this has not been proven, but what I believe is that excessively rewarding food―excessively palatable food can actually increase the level of body fat that that homeostasis system decides to defend against changes.

Chris Kresser: Right. So basically we’ve got a couple of things in general that disturb the set point. One, you can say is inflammation of the brain on a really general sense. But specifically inflammation of the hypothalamus. And the other is the food reward system. Which I think you mentioned―you know―Seth Roberts first talked about in his Shangri-La diet book. Which is kind of a physiological and psychological system where we begin to associate certain flavors with certain psychological and physiological response. Like feeling satisfied or just―you know―the emotions that are produced when we eat that response―the food reward system.

Okay, so in terms of inflammation of the hypothalamus, you wrote a great series about this a while back on your blog. But can you maybe summarize for us the main dietary and lifestyle factors that would contribute to inflammation of the brain.

Stephan Guyenet: Yeah, so. My thinking has evolved a little bit on this since that post. So there are some additional factors now that I think play―that I think potentially play an important role.

Chris Kresser: Okay.

Stephan Guyenet: I just want to be clear that this is all pretty speculative. These are factors that I think are good candidates for being responsible for that inflammation. But, I cannot―you know―there’s no evidence proving that these factors are involved in brain inflammation and obesity. Just my educated guesses.

Chris Kresser: Okay, we won’t hold you to it.

Stephan Guyenet: So―okay. So, at this point I think that one of the dominant factors in inflammation of the―of basically all tissues, but probably including the brain―is actually energy imbalance. So what I mean by that is―consuming more calories than your body can constructively metabolize. So when you put excess energy on cells or on tissue or on an organism it results in inflammation and insulin resistance. And I think that this is probably one of the main factors behind the kind of inflammation and insulin resistance and metabolic disturbances that you see in the modern United States today.

Chris Kresser: Right.

Stephan Guyenet: I think energy imbalance is a major factor. And one of the symptoms of that is obesity, but―one of the signs of that is obesity. But, you don’t necessarily have to be obese to be an energy imbalance. You can still be eating more calories and not necessarily be obese.

Chris Kresser: Right, and Stephan―would that work the other way around? Like long term caloric restriction energy imbalance in the other direction, also cause that inflammation, you think?

Stephan Guyenet: Not to my knowledge. I mean, if anything the reverse seems to be true. If you look at studies of people who have been restricting calories long term―I’m not saying that’s the optimal thing to do for your health. But, it seems to increase insulin sensitivity and decrease inflammation if anything. At least―at the very least compared to the average the person who’s probably over-consuming calories.

Chris Kresser: Right, right.

Stephan Guyenet: So I can’t speak―you know―if you compare that to someone who’s in perfect energy balance then maybe not. But, compared to the average person it’s certainly been proven that in insulin sensitivity and inflammation.

Chris Kresser: Right.

Stephan Guyenet: So, couple of other factors that we talked about were an imbalance of Omega-6 and Omega-3 fat. That’s a relatively―you know, I’ll admit―a more controversial one. I think that at a minimum Omega-6 overconsumption of Omega-6 fat can suppress the metabolism of Omega-3 fat. That’s pretty well demonstrated at this point.

So, I think that since Omega-3 is intimately involved in resolving inflammatory signaling―that that’s a potential mediator of brain inflammation. And not only that, Omega-6 fatty acids are the precursors of a number of things that are involved in body weight regulation in the brain. That kind of like modulate those systems. Like eicosinoids and endocannabinoids. And in fact, one of the things I talked about on the last show was Rimonabant which is basically reverse marijuana―

Chris Kresser: Right.

Stephan Guyenet: that causes depression to appetite. And it is somewhat effective although it has some nasty side effects. And so if you have an excess of Omega-6 precursor it’s possible that you can have an excuse of endocannabinoids. And actually they’ve shown that that’s true when you have a deficiency of Omega-3 fatty acids. You get excessive eicosinoid production and it favors fat mass to some extent.

Chris Kresser: Right.

Stephan Guyenet: So that’s one thing. There’s the gut dysbiosis that we talked about. We know at least in animal models that gut flora is a causal factor in fat mass but somehow that’s modulating the system. It’s not quite clear how that’s happening.

And then another thing that I’ve come to appreciate is cooking temperature as a mediator of inflammation. So there are a number of studies now showing that gentle cooking methods like steaming or boiling or gently braising in some liquid lead to better insulin sensitivity and less inflammation then high heat cooking methods. Then eating a diet of the same foods cooked by high heat like roasting and broiling and grilling and frying.

And that’s particularly true when you look in people that already have some sort of problem like diabetics.

Chris Kresser: Right.

Stephan Guyenet: Massive, massive differences in inflammation between those two diet styles in diabetics. Very significant. But, they’ve also noticed that to a lesser extent in healthy normal people. So, I think that’s an important factor and that’s something I focus on in my own diet. Although I haven’t written about it on the blog yet.

Chris Kresser: Yeah, that’s really, really interesting Steph. And I’ve heard a little bit about this, but I hadn’t heard that there was such a dramatic difference in people with preexisting metabolic irregularities. You know―from people whose metabolism is essentially intact.

Danny Roddy: So Stephan, if I get this right, you’re saying Aajonus Vonderplanitz was right all along?

Stephan Guyenet: Exactly. Actually I am. Him and I are the same person.

Chris Kresser: Yeah, raw meat Paleo, woohoo.

Stephan Guyenet: That’s right. Don’t forget to make it rot a little bit first though.

Chris Kresser: Fermented raw meat―sorry. But definitely bust out that crock pot if it’s have sitting in your cupboard for a while.

Stephan Guyenet: Yeah, and I don’t think―I’m definitely not endorsing becoming a―you know―raw food person. But I think that cooking food gently is in a general sense healthier then cooking it by more high heat methods.

Chris Kresser: Right, well that makes sense when you consider the fatty acids that are present in meat and how fragile―and you know―they are to heat.

Stephan Guyenet: Yeah, there are a lot of things in food that are fragile to heat. And there are chemical changes that occur with heat. And those are dependent on the amount of heat you put on something.

Chris Kresser: Right.

Stephan Guyenet: So basically anytime you incorporate water into your cooking whether it’s steam or brazing or whatever. You’re going to make it a very gentle cooking method.

Chris Kresser: Poached eggs.

Stephan Guyenet: There you go. I love poached eggs.

Chris Kresser: No more scrambled eggs.

Okay, so―let’s see. You mention a micronutrient deficiency. Especially vitamin D. Do you think that plays a big factor here still?

Stephan Guyenet: Yeah, I think it can play a role. I mean, it’s not clear to what extent it can play a role but there are some signs that it could be a factor. And there was a study that came out pretty recently from China, where they looking at micronutrient supplementation. They had a kind of comprehensive low dose supplement. And that caused some pretty impressive metabolic improvements in those people. So, some fat loss, and some improvements in blood lipids.

That study needs to be replicated. It’s just one study. So I wouldn’t hang your hat on it quite yet. But, there are some interesting suggestions also in the rodent literature that nutrient status could affect these things. I mean basically―you know―what are minerals to―you know―many cases minerals are co-factors for enzymes and for different chemical reactions. They just don’t have a sufficient amount of co-factor. You can’t do what your body is supposed to be doing. So, you know it’s not really that surprising that these things might in some way influence the way your body regulates body fat.

Chris Kresser: Nor is it surprising in light of the modern diet and soil depletion, etc. that a lot of people might have micronutrient deficiencies.

Yeah, so of course there’s another big factor that effects the set point, and you mentioned it earlier and this is what you’ve been writing about in your current series. The Food Reward System. So, I read Seth Roberts book after I saw it on your blog. And I thought the history of it was kind of interesting. So why don’t you tell us a little about how this whole theory―you know, was discovered and came about?

Stephan Guyenet: Yeah, so―food reward… the reward systems have been most thoroughly characterized from the perspective of drugs of abuse. So Cocaine and Morphine and things like that. Addictive drugs are where―are how people worked out a lot of these systems historically and in the greatest detail. And it’s only now that I think really mainstream science is coming into line with the idea that this is a really important system for not only just food, not only food acquisition, but also potentially obesity.

And I mean―basically they were studying this from the perspective of drugs, but all along they knew that this system didn’t involve to deal with drugs. But what drugs do is they plug into a system that’s designed to reinforce behaviors related to things that are beneficial to the organism.

Chris Kresser: Sure.

Stephan Guyenet: So basically there’s this system that labels things as good or bad, based on whether they are hurting you or helping you. And things that are considered to help you are things like―you know―sex and warmth and food that the organism perceives are calorie dense and nutritious. And so―

Chris Kresser: All designed to help us survive and procreate.

Stephan Guyenet: Exactly, exactly. And that system was designed for a particular environment with a particular level of typical food reward accessible to people in that environment. So when you put things like drugs of abuse into the system, those are basically―instead of functioning via the typical external routes that rewarding things function by―by you know, sensory systems and all that. They go directly into the brain and stimulate those reward pathways that would be otherwise stimulated by those natural routes.

And so they kind of like short circuit the whole thing and create a very strong response.

Chris Kresser: Right.

Stephan Guyenet: Which is why they’re A, so pleasurable and B, so addictive.

Chris Kresser: Right.

Stephan Guyenet: And what I think is that basically when you’re in an environment that has an excessive amount of rewarding stimuli whether that comes from professionally designed industrial foods. Whether that comes from video games, television or whatever else that’s unnatural about our environment that we really like. I think that can kind of create a bit too strong of a stimulus that takes us outside of what the system is designed to handle.

Chris Kresser: Right.

Stephan Guyenet: And into a place where we’re doing pathological things. And so, some of the earliest signs that this system was important for obesity was―there may have been earlier studies as well, but the first that I’m aware of were in the 1970’s when they started using a diet for rodents called the cafeteria diet. And that’s basically a junk food diet where they feed rats or mice a variety of human junk foods.

And these junk foods, keep in mind―especially today, but it was true in the 70’s to a lesser extent as well―are professionally crafted to be maximally rewarding. I mean that’s the whole point.

Chris Kresser: Right. Right, that’s like eating Twinkies and big gulps and―you know―Cheetos, cheese doodles―like mainlining right into the food reward system.

Stephan Guyenet: Right. I mean imagine if you had―you know―a big gulp and then right next to it you had a competing brand. But instead of being colored red it was kind of like a dirty brown color. Would that be able to compete on the market. No, it wouldn’t. Because the color is actually part of the reinforcing quality of it.

Chris Kresser: Right, right.

Stephan Guyenet: A lot of it’s the flavor, a lot of it is other things. But, the visual appearance and the context in which you’re consuming it―that’s all―basically everything about it is part of the rewarding properties of it. And food manufacturers have learned to systematically exploit all those factors to try to get people to come back and buy their product over and over again.

One of the things that Seth talks about that I like―Seth Roberts―is that he coined this term, ditto foods. Because one of the things that cause foods to be maximally rewarding is if they are exactly the same every time. So if you go to a McDonalds in New York City and in L.A. and you get French fries, they are going to taste identical. And you’re expecting that and you’re wanting that. That’s part of the thing you like because consistency of flavor and all the other things that determine reward including the physical environment and everything else is what determines the strength of the rewarding property for the food that you’re eating―in part.

Chris Kresser: Right. Okay, so―the cafeteria diet―you know―we were eating all kinds of highly palatable foods that have been engineered by―you know―massive food corporations who know this. Maybe know it better than some scientists at this point. Seems to raise the set point, it sounds like what you’re suggesting. So what about if humans or rats eat unpalatable food. Does it have the opposite effect?

Stephan Guyenet: Yeah so, there have been a number of studies in rats that show when you put them on―take them from a highly palatable food and put them on unpalatable food, they will lose a lot of weight and―lose a lot of fat, I should say. And depending on the study, they’ll either lose all of the excess fat that they’ve gained or some proportion of it. But typically, it will be most of it.

And then there’s some even more interesting studies in humans. That I referenced in my blog. One of them I talked about in detail, and one of them I didn’t. But they show essentially the same thing and in particular there’s one, where they took people and put them on this diet―this machine feeding diet where they were sucking fluid through a straw basically that was coming out of this refrigerator. So it’s basically eliminating―it was a tasteless fluid―it was basically eliminating all the reward―almost all cues that could be associated to the reward value of this food.

So no flavor, no texture, you’re not even really getting it in most of your mouth―it’s going straight down your throat because it’s through a straw.

Chris Kresser: Yeah.

Stephan Guyenet: So there’s almost no cues whatsoever. No color. There’s no social, environmental aspect.

Chris Kresser: Right.

Stephan Guyenet: So just―they told them, whenever you want drink out of this straw and have as much as you want. So they took lean people, put them on this thing. They consumed a normal amount of calories, their weight stayed extremely stable. And then they took obese people and put them on this same diet. And the result was absolutely remarkable. They barely ate any of the food. And they tested this on―I believe they said a total of five or six obese people so―a relatively small study. I haven’t seen any follow-up. But―

Chris Kresser: That’s amazing that there hasn’t been. Because this was like 50 years ago, right? In the late 60’s or 70’s or something?

Stephan Guyenet: I think it was in the 70’s but I’m not really sure.

Chris Kresser: But long enough ago that there could have been a follow up by now.

Danny Roddy: The picture on your―I’m sorry―The picture on your blog is like from a bad science fiction movie. It’s so funny. The machine with the fridge.

Stephan Guyenet: I know. I know. The nurse, the nerd outfit. Drinking out of the straw is pretty funny.

Chris Kresser: Yeah like with a foot peddle or something. You just kick it and the stuff goes right down your throat. Just not to get too far off track, but what was in there? I mean we know it was colorless, flavorless. But what was the actual nutrients that they used?

Stephan Guyenet: Oh, okay. You know I had a reader email me actually recently. He ended up getting his hands on the ingredients for that stuff. And I don’t remember all the details. I wish I had it on hand but it’s―they lifted the macronutrient composition of paper. I think it was 50 percent carbs. 30 percent fat, and 20 percent protein or something like that. It’s basically based on dairy and some kind of sugar or starch. And then vitamins and minerals. And some kind of like oil emulsion.

Chris Kresser: Right

Stephan Guyenet: Something like that. It’s―

Chris Kresser: So probably vegetable oil of some sort, huh?

Stephan Guyenet: Yeah, I suspect it was some kind of vegetable oil but I’m not totally sure. And the composition of that stuff has changed over time. It’s some kind of brand name liquid food. And―

Chris Kresser: Right, right. Well that’s like―

Stephan Guyenet: Anyway so they―

Chris Kresser: Go ahead.

Stephan Guyenet: Go ahead. Well, I was just going to say―

Chris Kresser: I was just going to say―

Stephan Guyenet: Go for it, go for it―you.

Chris Kresser: Yeah, you also―I mean, speaking of liquid food. There was this other study you mentioned where rats that eat strawberry and vanilla Insure which is a liquid formula that usually―tube fed that patients in hospitals don’t get fat. But the ones eating the chocolate flavored ones do.

Stephan Guyenet: Right. Yeah, yeah. And I thought that was very interesting. That was kind of like the thing that started my cognitive dissonance about this whole food reward thing.

But anyway, back to the study with the machine feeding. So the obese people but not the lean people started consuming a very low amount of calories. If I remember it was like―somewhere in the 200 to 500 calorie range.

Chris Kresser: It was 200. I just―because I was reading that yesterday. I could hardly believe it. I thought I was misreading it.

Danny Roddy: Same here.

Stephan Guyenet: Yeah, extraordinary. Yeah it’s―

Chris Kresser: And they did it not just for a couple of days. Like for a while they were eating only 200 calories and not feeling―saying they weren’t hungry at all.

Stephan Guyenet: Exactly. Yeah, they were eating as much as they wanted. They were not hungry. And they were eating an extraordinarily low number of calories. And they were burning fat at an extraordinary rate. And what I think basically happened is that almost zero palatability food―almost food reward lowered their body fat set point to a much leaner level. And they just began to shed those pounds very rapidly―without hunger. Because basically their body said―whoa hold on there, all of a sudden we have way more fat then we want. We have all this leptin hanging around and we’re going to try and get this back down to the level that we think is appropriate now that the food reward has been reduced.

Chris Kresser: Right, so it seems like a couple of things. Would you say the difference between the set point and where someone’s weight is will determine the rate of weight loss? Because you mention that the lean people did it―and you know, they didn’t really experience any weight loss. But the obese people did it and then they experienced this dramatic weight loss very, very fast―weight loss.

Stephan Guyenet: It should determine. It should absolutely determine the rate. Because if you take animals and you inject leptin into them, the amount of weight that they will lose in response to that leptin and the amount that their appetite will be suppressed is proportional to the amount of leptin that you inject.

Chris Kresser: Right.

Stephan Guyenet: So basically an obese person has a lot of leptin. And if you drop their set point down to half of what their current fat mass is, if they’re still carrying that fat mass they have a tremendous excess of leptin. But if you just drop your set point down a little bit then they only have a small excess of leptin. So it’s kind of the equivalent of injecting a massive dose of leptin into a leptin sensitive person, versus injecting a small dose of leptin.

So yeah, you should expect a higher rate of fat loss in the beginning when that system is receiving a very strong stimulus.

Chris Kresser: Right, that makes perfect sense. So I know a lot of people are listening to this and probably wondering―you know―they know someone or maybe they themselves are the type of person that could like eat―you know―Skittles for breakfast, and Cheetos for lunch and have―you know―dunkin donuts for dinner and they never gain weight.

And then there are the people who eat only―you know―relatively small amounts of those highly rewarding foods. Or even none at all. And they’re gaining a lot of weight. So do we know anything about why highly rewarding food increases set point in some people but not in others?

Stephan Guyenet: Well, different people are differentially susceptible to the effects of highly palatable foods. So it’s known that there’s a lot of individual variability in the response of the reward system in the brain. Which has been relatively highly characterized. And there are fairly large differences in how that responds to foods between individuals. And in addition―you know―we have this system where there’s basically―there’s two control centers that I’m envisioning.

There’s the homeostatic system which is actually the main control of body fatness. And then there’s this palatability food reward system that’s influencing the homeostatic system and vice-versa. But―where was I going with that? Yeah, so I think it’s also going to depend on the relative strength of those connections between those different areas.

And you know, there’s a lot of variation between different people. And there’s probably differences in the balance of which of those systems is dominant over the other between different individuals. So, I think both differences in the reward system―individual differences, and how people respond to food that have already been fairly well demonstrated. And there’s even some genetic basis for some of that.

And differences in the homeostatic body weight regulation system and how those two systems interact―I think those could easily explain individual variation in body fatness and response to palatable foods.

Chris Kresser: So could we say like―in the same way that you hear somebody has an addictive personality and they’re the type of person that’s more likely to get hooked on drugs or alcohol or something like that that there might be a subset of people―and maybe it’s the same set of people―that is more likely to have their set point shifted by these highly rewarding foods.

Stephan Guyenet: Yeah, that’s correct. And that’s actually been shown. And it’s been linked to genetic differences in dopamine signaling. So food reward is highly linked with dopamine signaling, and there are dopamine projections going right into the hypothalamus―that is the part that is the main controller of body fat. So I think that―yeah, and it’s already been shown that people with certain types of genes that influence that dopamine signaling in certain ways are both more susceptible to compulsive eating behaviors and fat gain and non-eating compulsive addictive behaviors.

Chris Kresser: That’s interesting because―

Stephan Guyenet: And they would be more susceptible to rewarding things in general basically.

Chris Kresser: Yeah, and I bet some people think―oh, that’s lucky. You know if you’re one of those people that’s not susceptible you’re lucky because you eat all that food and you don’t get fat. But if―it’s kind of, you look at it the other way around. If you’re one of those people and you eat all that crap and you don’t get fat you probably are one of the people that’s going to keel over and die of a heart attack when you’re fifty-five. Because you never get the wake-up call.

You know like―gaining weight for a lot of people is a sign that something is not going right. And it’s a sign that―you know―maybe something should be done about it. But, I don’t know. That was just a random thought I had about it.

Stephan Guyenet: Yeah, I agree. I think it’s the canary in the coal mine. And, I mean fat gain―especially moderate fat gain. To the point of overweight but not obesity, is not particularly bad for your health. I mean some people would even argue that it’s good for your health. So, I think that―you know―that’s a relatively less dangerous thing then some of the alternatives in terms of bad health outcomes.

Chris Kresser: Sure. So, another question I’m sure a lot people have is how this whole food reward theory and how it relates to homeostatic hypothalamic regulation of set point explains the effectiveness of some of the more popular fat loss diets like Atkins and South Beach and―you know―the low fat diets.

Stephan Guyenet: Yeah, it’s really quite simple. I mean if we start with low carb and low fat diets. Fat and carbohydrate are both major food reward elements. So if you cut out one of the main elements of food reward, you’re going to be reducing the rewarding quality and the palatability of your diet, then you’re going to reduce your set point. And that’s exactly what you see.

Chris Kresser: So even if have still one thing that’s rewarding, you’ve knocked out another, so the overall reward is less.

Stephan Guyenet: Yeah, that’s correct.

Chris Kresser: Yeah, yeah, okay.

Stephan Guyenet: And then―you know―you have all these other guys that are restrictive in various ways. And many of them restrict typically processed and industrial food. Those are going to be the most rewarding foods to most people. So those are going to have a tendency to be somewhat effective. Even if―you know―their rationale for why their diets work are some completely different reason. They all kind of plug into the same system and they are all effective in that way. So I think that explains why you have all these low fat diets that―you know―from the 1980’s that are concluding at the end―you know―eating fat makes you fat, reducing it makes you leaner. So let’s eat less fat.

And then now you have these low carb studies that are concluding the opposite. Carbs makes you fat, so let’s eat less carbs. But the fact is, neither one is inherently fattening. It’s the fact that it’s a palatability factor. It depends on the diets context.

Chris Kresser: Right.

Stephan Guyenet: So if you add carbohydrate to a low carb diet, you’ve increased the food reward value of that diet. If you add carbohydrate to a high carb diet, you’re not increase the food reward. You might even decrease it. So it absolutely depends on the dietary context.

And then there’s other diets like―well there’s a bunch of other diets. But the other one I want to talk about is the paleo diet. And the paleo diet reduces those rewarding qualities considerably. Because―you know―there’s a lot of different versions of the paleo diet that―you know―many versions are reducing processed  food. They’re reducing salt, they’re reducing sugar, they’re reducing free glutamate. They’re reducing these―you know―processed professionally crafted highly rewarding foods.

And the thing that I really like about the Paleo diet is it’s able to achieve a lower food reward level while still remaining highly nutritious.

Chris Kresser: Right, and still―

Stephan Guyenet: Because you look―

Chris Kresser: Including all―and not really necessarily being about macronutrient ratios.

Stephan Guyenet: Exactly. And you can look at other diets that are somewhat effective for weight loss. I mean―you know, the more extreme the diet gets, and the more restrictive, often the more effective it will be for fat loss. And you can look―you can go from  low fat diet and say okay, this works a little. Low crab works somewhat. And then you can go the vegan diets. And these diets―you  know, people go on these things and they lose a substantial amount of weight.

And reduce their calorie intake quite a bit. And because of that, because their energy balance is improving their health in many ways does legitimately improve. You know―insulin sensitivity and inflammation go down and things like that. And so then they conclude that―okay animal foods are causing obesity and inflammation and insulin resistance. But that’s not what’s actually happening. What’s actually happening is they’ve created a diet that tastes like crap. So you know, they reduce their food reward and the fact that their energy balance is coming back into line. And the fact that that is a dominant factor in health is the reason those people’s health is improving.

Chris Kresser: That’s right.

Stephan Guyenet: And so that’s all well and good. Except for the fact that it’s not a nourishing diet. So in the long term you’re going to run into problems.

Chris Kresser: Right and that’s so―I’m so glad you brought that up. Because I always―I get, you know probably an email a day from some raw food vegan saying well―you know. So many like―Dr. Dean Ornish and so and so. Joel Fuhrman, you know. They put their patients on a vegan diet and they get better. And I say right. What were they eating before? You know. Where are they coming from?

And this is just yet another―you know―I was explaining it more in the context of what they took out of their diet, instead of what they added in. You know, like they stopped eating seed oil, stopped eating processed and refined cereal grains. Stopped eating sugar and excess fructose. Stopped eating―you know―processed soy.

But this is a whole other angle. It’s not only what they removed in terms of nutrients. It’s what they removed in terms of flavor. Yeah.  It’s really fascinating.

Stephan Guyenet: Absolutely.

Chris Kresser: So speaking of that there’s a pretty interesting part of Seth’s book for me was that―you know―certain flavors that when we first try them don’t―we don’t like them. Or―you know―they’re nothing special, but over time they become more appealing. I think one of the examples he used was Cilantro. That―you know―Cilantro usually is put on―you know―foods that are highly rewarding. Like maybe Mexican food with sour cream and―you know―guacamole and lots of other hot―really tasty kind of rewarding flavors.

But if you just ate Cilantro the first time and kept eating only Cilantro, you’d probably never get a―that flavor would never be appealing. So what is that―can you talk a little bit about that and how it relates to this whole food reward concept?

Stephan Guyenet: Yeah, so Seth focuses on associations between flavors and calories that form over time and how those influence the set point. And that’s also something I think is central to this whole thing. And so basically what happens is you have these properties that are inherently rewarding about certain foods. Like calorie density and fat and starch and sugar and free glutamate which is―you know―MSG or the meaty flavor mommy. Salt and a variety of textures and some aroma like esters found in fruits.

And then those―you know―when you eat foods that contain those, your body kind of picks up on the things that are associating with that. So what flavors are coming along with it? Where did you eat it? Who did you eat it with? Etc. And it basically attaches the positive associations to those factors that were associated with that food. As well as the positive value that’s inherent to that food.

So if you eat―you know, one of the things I like to talk about is―you know―greens or spinach with butter on it. The butter is inherently rewarding. That’s really tasty food to almost anyone.

Chris Kresser: Right.

Stephan Guyenet: But spinach is not. And―you know, especially as children people hate spinach. Most people hate spinach or brussels sprouts or whatever you want to say. But if you eat that with a dense source of calories or something that’s highly rewarding, over time you’re going to form an association with that. And it’s going to taste good. So that’s basically how it works. That’s how we evolved over the course of our lifetimes to understand what foods we should be eating, and what foods we shouldn’t. The brain decides whether flavors are good or bad based on what they’re associated with and how it ranks the values for the food that you’re eating.

Chris Kresser: Yeah. I always cringe when I see parents like trying to force their―you know―three or four year old kid to eat spinach and brussels sprouts and broccoli when they’re just like steamed with nothing on it. It’s pretty obvious why they don’t want to do that. And not to mention the fact that to absorb a lot of the nutrients in those vegetables you need fat soluble vitamins that are found in fat. And I wrote this post a while back called have some veggies with your butter.

Which was―you know―basically about this topic. But, so what’s interesting I think about this for me is it’s not just about flavor. Because it―you know―you have traditional cultures who ate very stinky foods, right? They all―like, you know―fermented cod liver oil or anyone who’s eating poi or you know. Most traditional cultures had this stinky foods which you would think because they’re super flavorful might increase the set point. But what they didn’t have is the super caloric dense―you know―artificially manufactured foods to go with those stinky foods that would really increase their set point.

Stephan Guyenet: Yeah so, I think that those foods―you know―fermented foods with the strong flavor for example are more rewarding than those same foods before those fermentation steps. And you know, they were considered typically delicacies in those cultures.

Chris Kresser: Right.

Stephan Guyenet: But what you have to think about is that―you know―those strongly flavored, peculiarly flavored foods were not usually the dominant source of calories in these cultures. They were typically delicacies that were―

Chris Kresser: Or condiments.

Stephan Guyenet: Yeah, and―you know―you mentioned Poi. That’s obviously an exception. That was actually a staple food in Hawaii. That’s a fermented Taro. But, I mean, it’s not a strong flavor. It has a little bit of tartness, but it’s actually not a very strong flavor.

Chris Kresser: Right, Taro is pretty bland itself.

Stephan Guyenet: Yeah, Taro is quite bland. And so―but if you’re talking about fermented fish and fermented cheeses and things like that. Those were delicacies that were eaten in relatively modest quantities along with other foods that were relatively less rewarding. But you know, you can―you know―those foods I’m sure contributed to the reward value of their overall diet.

Because you can take rats and you can actually add bitter flavors to rewarding food and it will actually make it more rewarding in some cases. Because just having a flavor to associate that food with allows it to form a stronger association, stronger food reward association with that food. So it’s like beer, you know. That was an example I used on my blog. People end up enjoying the bitterness of beer even though bitterness is inherently aversive flavor.

Chris Kresser: Right.

Stephan Guyenet: If it’s continually paired with something you like, then it can actually in a specific context end up becoming pleasurable.

Chris Kresser: Right, I think most people can remember their first sip of beer and the―you know―the look on their face they had after it.

Stephan Guyenet: Oh man, yeah. I used―my parents when I was a kid, they would pour me a little bit of beer just so I could taste. And oh man, I used to pretend like I loved the stuff but really I hated it.

Chris Kresser: What are you people―you people are crazy. What are you thinking.

Stephan Guyenet: I know, I wanted to be an adult, so I would have my little beer, but.

Chris Kresser: Yeah. You’re sitting in the back of like a VW bus when you’re sixteen―you know―having your first sip of beer and trying really hard not to look like you’re about to spit it out.

Stephan Guyenet: Yeah.

Chris Kresser: So let’s get to the meat of it here in terms of practical applications. Like as people are waiting for us to develop our paleo food tube refrigerator machine  that we can sell to them, what can they do to put some of this into practice? If someone’s―you know―dealing with―you know―obesity or overweight and they’ve tried everything. And you know, all the different diets and they haven’t been able to lose any weight. I mean Seth has some interesting ideas about that. And I have a few ideas about Seth’s ideas, but I’d love to hear your―you know, practical tips.

Stephan Guyenet: I think that―you know―overall framework, the most general thing I can say is that the most important thing is a switch from a pattern of eating commercially produced foods to a pattern of eating home cooked simple gently cooked foods. So I think that’s going to be a strategy that will be useful for many people. There will be a subset of people that that’s not going to help or at least not going to help to the degree that they would like.

So, and I’m going to expand on this more on my blog over time but―I haven’t fully developed my ideas, but basically what I have in mind is kind of a series of different levels that you can go through. Different levels of reducing the food reward properties of your diet depending on what kind of results you’re looking for and what type of results that you’re getting.

So, the first stage would be kind of just getting the low hanging fruit. So that would be eliminating sodas and snacks. Not eating food between meals, which tends to be processed convenience foods. Not eating any source of liquid calories, especially between meals. And especially sweetened liquid calories. So that would be kind of the low hanging fruit.

The next level would be to reduce or eliminate processed foods in general. Cook all your food at home personally using simple, gentle cooking methods. Reduced sugar intake as much as possible.

And then, if that’s not working, or if that’s not working to your satisfaction you move to the next level. Which would be reducing additional palatability factors. Things like sugar and salt and meatiness. So things like Soy sauce and fish sauce and yeast extract and broths would be things that fall into that meatiness category.

Some people respond well to restricting fat or carbohydrates. So those are major palatability factors. And the degree to which people respond those differs on an individual basis. But I would also say at that level to make your food very simple and not really flavor it. Just eat plain vegetables. Plain starches like potatoes and rice and meat. And nuts or whatever. It doesn’t mean―you don’t necessarily have to restrict macronutrients. And I would actually say ideally that you probably shouldn’t and you only should do that if necessary.

Because I think that the most nourishing diet is one that’s not restricting macronutrients and not restricting micronutrients.

And then the next level―and I’m not recommending this, but I’m just putting it out there as a possibility for people who―you know―are up to the challenge and―you know―really want―you know―are really intent on making a change. Make your diet not only plain with―you know―not very many flavors, and not only very simple. But also very monotonous. So only eat just a few types of food. You know―make a plan where you’re eating basically the same thing over and over and over again. Now, plan it out so that you’re getting a good spectrum of nutrients so it’s a nutritious diet. But make it repetitive and not particularly attractive.

So you know, an example of this―and I’m not saying―I’m not―you know― I’m not recommending that anyone do especially this version of it. Is the 20 potatoes a day guy. You know, he ate basically nothing but potatoes for two months and his health improved dramatically.

And I would say―well, let me take that back. His many markers of health improved including his weight. Went down a leaner level. His cholesterol went in a direction that I feel is positive. His fats and glucose decreased. So it seems to be a positive change. And again, I’m not recommending that anyone eat nothing but potatoes. Or nothing but anything of any single food. Although I will say that potatoes―you know―if you were going to pick a single food, you probably couldn’t do much better then potatoes.

But again, I’m not recommending that because it’s not really nutritionally sustainable.

Chris Kresser: Right, nor will you have a bestselling book on your hands if you do.

Stephan Guyenet: Yeah, that right. That’s right. But yeah, it―that’s an example of a monotonous diet that was highly effective. And you know, he’s just one individual but if you look around you can find a lot of other examples of that. And that monotonous tube feeding diet I was that I was telling you about. Or straw feeding or whatever you want to call it―is another example of that. And there are other examples in the literature with―you know―larger sample sizes that are showing very similar things. So that would be kind of like the highest level.

Another thing I want to mention is Seth Roberts book, the Shangri-La diet. He has a simple strategy in there that really doesn’t involve restricting yourself at all. It involves taking in calorie containing flavorless foods between meals. As a way of king of tricking the system into the lowering the set point.

And you know, I’ve corresponded with Seth a little bit. And you know, I’ll just say that―you know―Seth, he’s not just an internet black ball. He’s a PhD in psychology and he―

Chris Kresser: At Berkeley, I―you see―at Berkeley right? I should go say hello.

Stephan Guyenet: Yeah, that’s correct. So, you know―he has some scientific backing for what he’s saying. And he also does some self-experimentation.

The thing that I never―that was never very clear to me is what―to what degree do these effects maintain over the long term? And are there any negative health consequences in the long term. That was a question that he was not able to answer. And that his―that’s poking around his Shangri-La diet forum was also not able to answer.

But, that being said―you know―that’s a possibility that people can look into if they’re interested. I’m not necessarily endorsing it. But―

Chris Kresser: Right.

Stephan Guyenet: That’s a possibility that―you know―people can consider. I think another thing that people―

Chris Kresser: So let me just―Stephan, just for the people who haven’t read this book. What he suggests in the book is eating a relatively small amount―say 200 to 400 calories depending on how―where you’re starting from. How overweight you are and how much weight you want to lose―of unpalatable food. Just adding that to your diet. Not making any other changes in your diet really.

And the two things that he suggested and he did for himself on this experiment was sugar water―so in the beginning he added just liquid fructose―or maybe it was powdered fructose to water. And which you would think would be―is sweet and would have a sort of strong effect on the reward system. But he says―I’m curious about this too, Stephan. That the brain doesn’t respond to it that way. The brain responds to it as relatively bland taste. Because we basically come out of the womb―you know―liking that taste. And it’s―we―our brain responds to it as a bland taste.

And then the other thing―after a couple of years, a colleague told him about extra light olive oil. Which is unlike extra virgin olive old, has almost no flavor. And so then he started using a maybe a table spoon or so of the extra light olive oil each day. And making no other changes, and that would reduce his caloric intake significantly. He said he would go from eating―you know―two meals a day to one meal a day, and never feel hungry and lose quite a bit of weight.

Stephan Guyenet: Yeah, so the idea is that it reduces your set point. And therefore the extra calories that you’re consuming between meals are more than compensated by a reduction in calorie intake from other sources. So I’m glad you brought up this thing about sugar. Because this is probably something that other people are wondering about. I think this underlines the fact that palatability involves multiple factors. And one of them is actually flavor so―or, I should say smell would be a more accurate way of saying it.

So, for example if you drink Coca-Cola, you’re not just drinking sugar. You’re drinking sugar with flavoring in it. And your brain makes a very strong association between the sugar that it likes and the flavor of that Coca-Cola which becomes pleasurable over time. So sugar itself―plain sugar with nothing else―no other flavor to it, is not necessarily that rewarding. But when you add it into something that has a flavor and has other things your brain can associate with that, then all of a sudden it becomes very rewarding.

And sugar is one of the most strongly rewarding things there is in the context of other foods.

Chris Kresser: Right.

Stephan Guyenet: So, it’s interesting. And I think it underlines some of the complexity of the system. I’ll also say that that―you know―straw slash tube feeding study I was telling you about. I believe that there was a significant amount of sugar in that diet as well.

Chris Kresser: So―

Stephan Guyenet: But there was almost no flavor.

Chris Kresser: You know, and there’s of course this other question of what’s the health consequences of eating sugar―adding sugar water to your routine every day. Or even adding extra light olive oil. I think probably not hugely significant at the levels―quantities―we’re talking about. But, I was thinking about this a little bit, and I’ve actually done some experimentation on myself and some of my willing patients which is great. Because I get―

Stephan Guyenet: Using Seth Roberts methods?

Chris Kresser: Yeah, yeah.

Stephan Guyenet: Okay.

Chris Kresser: Not on myself, to lose weight. Because if anything, I―you know―I definitely don’t need to lose weight. But just to try it. And see how it felt, and what the effect was. And rather than using sugar water or extra light olive oil. I’ve tried two different fats. One was expeller press coconut oil. So not the extra virgin coconut oil which has quite a strong coconut flavor, which I’ve already associated with a lot of really tasty foods. But the expeller press version which is actually pretty flavorless. Pretty bland, especially compared to the other one.

And then MCT oil, which is also pretty flavorless and it’s definitely not something I have any association with in terms of flavor. And―you know― I don’t know if those will work the same as sugar water and extra light olive oil. But they strike me as being healthier alternatives since they’re―you know―either long chain saturated fat or medium chain triglycerides.

I mean, and so my experience has been that absolutely it’s decreased my appetite. The last two or three days I’ve only eaten two meals. And which―that’s not super unusual for me because sometimes I intermittent fast. But I’ve just literally not been hungry enough to eat more than two meals.

And then I’ve had a couple of patients who’ve done this who’ve lost a pound a day over―you know―like an eight or nine day period. So I mean this is like an N3 experiment here. So this is nothing to write home about yet, but pretty interesting nonetheless.

Danny Roddy: Real quick―

Stephan Guyenet: Yeah, that is very interesting and you know I think his methods are promising and I would like to see―you know―more information about the long term effects over time. Because if it’s true, it offers a relatively easy way of manipulating the set point via the food reward system.

Chris Kresser: Right.

Danny Roddy: Does he ever mention the French in his book? Because they’re known for having such a high―like cheese and wine―like very robust tastes in their diet. Is that―?

Chris Kresser: I don’t he does.

Stephan Guyenet: I don’t know if he does or not. But―you know, I have my own take on that. And that is that―you know, although the French are known for eating well, they’re also known for eating at home. And restaurant food in France is a special occasion. And industrially processed food is also consumed to a lesser degree then here. And of course that’s changing. The countries food system is industrializing―just as it is everywhere.

But, it’s still less then it is here. And―you know―they know how to eat well, but they make home cooked food that is actually―even though it might be more pleasurable to eat in many ways has a less of those qualities that make food excessively rewarding that are found in commercial processed foods.

Chris Kresser: Right. Right. So, we’re already at well over an hour here. I hope there’s at least two people listening to this. Why don’t we get to a few questions. We won’t have time to answer―of course all of them―there’s probably 60 or so questions that we got. But hopefully we’ve covered a lot of them. I think we have actually. And Danny, why don’t we just get into some of the questions.

And Stephan, if one of them―you know―we feel like we already answered, we’ll just skip it and move onto the next one.

Stephan Guyenet: Yeah, sounds good.

Danny Roddy: I feel pretty silly asking you this. Because what I change―what I eat changes every week. But Stephan, what do you consume daily?

Stephan Guyenet: Yeah, so a lot of people ask this question. Alright so, just in general I try to eat foods that are less processed. And processed in traditional ways and generally processed by me rather than in a factory. And so, I also try and eat things that are cooked relatively gently. So I favor things like steaming and braising and a little bit of water over broiling and grilling and frying.

So I’ll just walk you through what a typical days meals would be for me. My typical breakfast would be potato. Either one or two medium to large potatoes with a little bit of fat on it. Some butter or some red palm oil or some virgin coconut oil. I’ll have one gently cooked egg. I usually have some kind of vegetable. Usually it’s raw, sometimes fermented like sauerkraut. But often I’ll just have a raw carrot or something like that. And then I’ll just throw in a handful of nuts. Usually almonds or hazelnuts. Or some leftover rice and beans. And sometimes instead of the potato I will have kind of like sourdough savory pancake like the ones I was talking about on my blog. Either a thing that kind of like a [inaudible] or maybe buckwheat sourdough pancake. That would be my typical breakfast.

And then for lunch, I typically again will eat potatoes. Couple microwave potatoes. And then I make my lunches at home for the week. I’ll typically take some either ground beef or lamb―grass fed―or some chicken and cook it gently with some vegetables. Often there will be greens. Typically there will onions in there. A variety of different vegetables. And I just cook it very gently, very simply. I usually don’t add any kind of herbs or spices or salt. Sometimes I’ll add one or two herbs. Just very mild flavor. But usually, not even.

So that’s my typical dinner―or lunch. Lunches, very simple. And then for dinner I will often have some kind of either potatoes or sweet potatoes again. I’ll have often rice and legumes. So beans or lentils. And legumes are always soaked for 24 hours before cooking. And I cook them with some seaweed, usually with kombu for some iodine and flavor. And the rice―lately I’ve been doing a 50-50 mix of white and brown. And I will use my soaking fermentation method that I posted on my blog for 24 hours prior to cooking it.

And I’ll have often a little bit of meat. A little bit of wild caught fish. And then I’ll have some kind of vegetables. Often a fresh salad with a homemade vinaigrette or I’ll just have some raw or cooked vegetables. And then I’ll eat a little bit of goat dairy or sometimes a little bit of cow dairy. But mostly―most typically goat dairy. So and usually in fermented form. So it will be yogurt or cheese. And then I’ll have some nuts. Almonds, hazelnuts or cocoa nibs. And I usually have a piece of fruit. And then every couple days, sometimes everyday depending on how I’m feeling, I’ll have a small glass of wine along with dinner as well. Usually red wine, but I’ll drink white wine just as well.

Chris Kresser: Right, because you are French after all.

Stephan Guyenet: That’s right. And I guess one of the things blog readers don’t know about me. Is that I do a fair bit of brewing, and so I make my own wines and I also make some gluten free beers. So I’ll have those sometimes.

Chris Kresser: Nice.

Danny Roddy: Exclusive.

Chris Kresser: Can you send me some of that?

Stephan Guyenet: Sure. No, you’ll have to come up and visit.

Chris Kresser: Alright, sounds good. I―because I used to brew as well and then I stopped eating gluten and the thing that I―I don’t even miss bread or anything like that. But the thing that I miss is a good dark beer. That’s like―and I found gluten free darkish beer. In a store here locally. It was actually pretty good. But, I’d love to trade some notes with you sometime about that.

Stephan Guyenet: Absolutely.

Chris Kresser: So, just so everyone―you know―I imagine there’s some low carb listeners out there that think you’re 450 pounds because you eat six potatoes a day. This is clearly evidence that at least―it’s not about the macronutrient ratio usually. If you’re metabolism is intact that―you know―you can eat a relatively high carb diet like the Kitavans. And as long you’re not eating food toxins, and as long as you’re not eating a lot of processed food then your body should be able to handle it.

Stephan Guyenet: Yeah, that’s right. And there’s many cultures that will attest to that. And my diet has become more starchy over time, over the last few years as I’ve kind of gradually let go of the idea that carbohydrate is―you know―harmful―

Chris Kresser: Evil.

Stephan Guyenet: And behind―yeah―and behind obesity, etc. But one thing I just want to mention before I wrap it up about what I eat is that also I drink herbal teas during the day. I like to have a cup of herbal tea like―either hibiscus or tulsi tea which is basil tea. Or decaf green tea. I rarely drink caffeine. I’ll have it maybe once a week, just for pleasure. But not on consecutive days. I virtually never snack. I virtually never eat between meals. And I never consume any kind of soda, juice, milk or any kind of caloric beverage between meals.

And my diet is―I would say just estimating, it’s probably 47 to 50 percent carbs. 38 to 35 percent fat, and probably about 50 percent―or 15 percent protein. Just a very rough estimate.

Chris Kresser: Right, which is another thing that’s often surprising for the low carb or paleo type people. You know―that they should be eating a really high―that they have to eat a high protein diet to lose weight. You know―that’s another common misconception. Okay so, why don’t we choose―Stephan why don’t you choose one more question that is maybe the most interesting for you to answer. Because we’re coming up on 90 minutes and I think even the most diehard committed of our listeners is starting to look at their watch, so.

Stephan Guyenet: Okay, alright. Sounds good. I think―alright let me see here. There is one thing that I think would be interesting to talk about that a lot of people have asked me about. And that is how are―why do people gain weight with age. Especially post menopausal women. Why do they tend to gain weight with age whereas they were able to maintain leanness when they were young.

So I think basically there’s two different systems that are interacting to set the level of fat mass, and that’s the homeostatic system that’s the fat mass regulatory system. Which is basically the one that does the work. And then there’s the food reward system that’s influencing it. And I think that with age you can actually get changes in the signaling of that homeostatic system.

So you can actually develop with age a gradually increasing level of resistance to the hormone leptin. So the signals not quite getting through as well and your body has to increase fat mass to reach the same level of signal inefficiency. So that’s something that happens with age. It just kind of―in many people they develop an increasing baseline tone of inflammatory signaling. And that can lead to a resistance to leptin. It’s probably part of it, but the other thing―and this is particularly―this is relevant to women―I actually did quite a bit of reading on this recently. Is that estrogen effects leptin sensitivity.

So estrogen actually increases leptin sensitivity. So when a woman goes through menopause and her estrogen drops, it’s actually going to decrease the effectiveness of leptin to activate that whole system. So that explains A, why women gain weight when they’re―when they hit menopause. And B, why hormone replacement therapy can help women maintain leanness.

Chris Kresser: You know, that’s really interesting. And you know―might be from my perspective as a health care practitioner, I mean I have my own issues with certain types of hormone replacement therapy. Especially the creams which are free fraction hormones and bypass the natural regulatory mechanisms. But there are certainly other ways to address hormonal regulation in menopausal women. And that seems like a really potentially fruitful strategy for people in that group to lose weight.

Well Stephan, thank a lot. This has been fascinating. And I actually―I think it’s sort of just the beginning. I’m looking forward  to reading the remainder of your articles and I feel like there’s a lot of―my mind’s kind of spinning around right now with ideas for how to put this into practice with my patients. And I’m sure some people listening to this are really excited. So we’re grateful that you took the time to come and talk with us. And it’s always a pleasure to have you on the show. And we look forward to the next time you can come back.

Stephan Guyenet: Thank you very much. It was my pleasure.

Chris Kresser: Okay, take care Stephan.

Stephan Guyenet: Okay, you too.

Chris Kresser: Hey everyone. It’s Chris Kresser. I just want to make a special announcement. My new online home study course on supercharging your nutrition for fertility, pregnancy and breastfeeding―is now available. It’s called the Healthy Baby Code. And it’s designed to help you conceive naturally, have a smooth and joyful pregnancy and promote lifelong health for you and your baby.

Now the course contains about five and half hours of how to audio and video and more than a hundred pages of information in PDF format. And for a limited time only, I’m offering a introductory 25 percent discount for my blog readers and podcast listeners. So if you’re interested you can go to HealthyBabyCode.com. And make sure to check it out soon if you want to take advantage of the discount. Thanks again for listening and I’ll see next time.

Danny Roddy: That’s going to bring us to the end of this week’s episode. You can find all of Chris’s work at the TheHealthySkeptic.org. You can find me at DannyRoddy.com. Keep sending us your questions at TheHealthySkeptic.org using the podcast submission link. If you enjoy listening to this podcast, head over to iTunes and leave us a review.

Thank you for listening, and thank you for your support.