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My notes from the second segment of the debate (second half hour of it) and my comments below the notes:

• [SG 29m] The brain actually regulates body fatness. No one should be surprised by this.
• [GT 30m] One of the problems is «intellectual phase-lock» [a condition in which dogmatic beliefs prevent certain questions from being asked]. The obesity research community left out of its research endocronilogy in the 1960s, i.e. the hormonal/metabolic regulation of body fatness, oxidation, etc. Everything they have done since has been interpreted incorrectly. Leptin is a good example. They assumed what leptin does is control the brain, but perhaps a lot of what leptin does is done in the periphery. In the search for genes associated with body type all the genes act below the neck (insulin-regulated genes), but with excess body fat they decided they are in the head. The question is that when they look, they are programmed to think body fat is caused by overeating, so they look in the brain.  
• [SG 35m] They don’t start with any assumption.
• [GT 36m] Genes can have different jobs in different cells of the body, but if you think that the problem is in the brain, that’s where you look. 
• [GT 36m] Stephan’s book is supposed to be about obesity, but in fact you never mention anything about the hormonal regulation of fat accumulation. It is just not there and it has to be there. [we can hear the laughter of Guyenet while Taubes speaks] 
• [GT 37m] Stephan is the defender of the orthodoxy, and I’m the one who comes along and says «you have psychologists and psychiatrists running the field, while endocrinologists solved it». 
• [GT 37m] What has the brain to say about the fact that body fat accumulates in some parts of the body and not in others? [Again we can hear Guyenet laughing while Taubes speaks] 
• [SG 38m] When looking at the genes associated with total body fatness, the thing that causes obesity, genes related to the brain pop up, whereas when looking for genes related to the body fat distribution, we see insulin-related genes, for example in the people who have body fat around their waist.
• [SG 39m] [sarcasm about Taubes talking about leptin] «this is good», because he does not normally mention leptin. Researchers do not talk about the peripheral actions of leptin because it has been shown that the effects of leptin are via the brain, not because they wear blinders . [Guyenet taks about himself as a researcher: «WE focus»]. In the experiments in which the leptin receptors are knocked-out in the brain or in the hypothalamus you get obesity, which shows that the brain is a key site of action.
• [GT 40m] A key site of action. 
• [SG 41m] The brain is this site of action that causes this to happen. We understand very well how leptin works. People with obesity don’t lose fat because they have a higher set point in their adipostat. When a person loses weight there is a reaction in the brain circuits that regulate body fatness that drives an increase in their cravings and hunger. It does that until the fat comes back. Body fat is regulated by a negatively feedback loop that is controlled by leptin.
• [Joe Rogan 44m] When you are eating a sugary diet, a high-calorie diet, your body will get fatter, right? 
• [SG 44m] It depends on how many calories you are eating.
• [GT 44m] Leptin is not only produced in response to the size of the adipocyte, but also in response to the entry of glucose into the adipocyte, which is partly mediated by insulin. 
• [GT 45m] Everything that is said has two interpretations, depending on which paradigm you are looking at. And the paradigms are essentially different. 
• [GT 46m] 8 years ago Stephan and I first fell out when I acted inappropriately in the Ancestral Health Symposium. 
• [GT 46m] Knowing that more people are entering a room than leaving does not tell us why the room is getting crowded. In obesity, why you are getting fatter has been left out and people decided that overeating was somehow an explanation. 
• [GT 47m] To know what is the influence of the environment on obesity we must ask ourselves if  we can find an epidemic of obesity without this «modern food environment». And I found out about the Pima in 1902: poor, malnourished, suffering through famine for 40 years, and yet the women of the tribe, who do all the hard work, were obese. We can then disassociate obesity from the «modern food environment» and the ultra-processed foods. We have obesity despite the existence of famine. [We hear Guyenet laughs]
• [Joe Rogan 48m] What was the cause of the women becoming obese?
• [GT 48m] They were «reservationized» and they began eating western foods. You can find the same in the Sioux.
• [GT 49m] Any population transitions to a Western diet or western diet/lifestyle become obese and develop metabolic syndrome. Genetics aren’t that important thing, the important thing is what’s triggering it in the environment. I think it is certain foods. 
• [GT 50m] Double burden of obesity: we have obese mothers with malnourished children. And this occurs in populations that have not been able to «overeat». And if they could have eaten more, why are their children starving? How do we explain obesity in the mothers without assuming that the mothers are overeating? 
• [Joe Rogan 51m] Stephan, are there populations in the world that are obese and that are not consuming a Western diet, that are not eating sugary products? 
• [SG 51m] Probably not, because once you have an industrialized food system that is going to include sugar. But there are populations that eat a lot of sugar and are not obese.
• [SG 52m] Gary has told a story, his version of the Pima story. Let me tell you the version of the story that appears in the scientific literature. They were a society that depended on agriculture, but with the arrival of farmers (settlers of european descent) the river that supplied them was diverted and the government began to provide them with food: calorie dense refined foods, flour, lard and sugar. And they became very obese. Other Pima who, right accross the border, maintained their traditional high-carbohydrate and agricultural lifestyle, were much leaner and healthier.
• [SG 54m] Gary, you seem to believe that people can gain weight even if they are eating too few calories …
• [GT 54m] Yes 
• [SG 54m] These are very casual observations, story-telling. When you look at the data, what you see obese people consume between 20 and 35% higher than people who are lean. Those data come from the most accurate methods that we have. Gary’s model says that is a consequence, a result, of gaining weight, while my model says that that is actually required for the fattening effect to occur. What happens if you reduce the calorie intake by that same amount? It does not matter if you do it by restricting carbohydrates or fat, these experiments have been done, they lose weight.
• [Joe Rogan 56m] You’re saying that by consuming low amounts of calories but high amounts of sugar, it does not make sense that one can become obese that way. 
• [SG 56m] Right.
• [GT 56m] We can find cases where there is obesity without excess food, such as Trinidad in the 1960s. Two thirds of adult women were obese, and there was famine, malnutrition and stunted children. Data say that they consumed fewer calories than those recommended by the WHO for a healthy diet. The brain hypothesis does not explain why a mother is obese while her children are starving. If she has to eat superfluous calories to get fat, which is what that hypothesis says, why isn’t she giving those calories to her children? My hypothesis is that the explanation is that it is the macronutrient content of the diet what triggers obesity. 
• [GT 59m] There are experiments on which the animals get fat even if they are starving. 
• [SG 59m] They are experiments done on animals with mutations related to leptin.
• [GT 59m] The point is that if my body accumulates fat at intake levels at which a thin person can’t, I will gain fat eating the same amount. 
• [SG 59m] The caloric intake data for Trinidad are not reliable. There is no reason to believe that people were eating 1800 kcal/d and becoming obese. Accurate measures of caloric intake from people who say that they are consuming 1200 kcal / d, say that they consume more calories than thin people. What Gary says is only observed when inferior methods are used to measure calorie intake.
• [GT 1h1m] I insist on my question: obese mother with starving children. The existence of the starving children strongly suggests that there is not a lot of food available. And we have to explain the obesity in the mother. 
• [SG 1h1m] There are many reasons why a child may have malnutrition in a non-industrial situations. I don’t have an explanation but it is not necessarily for the reason that Taubes says.

It depends on how many calories you are eating

Guyenet, PhD, the same guy who just a few minutes earlier said that a diet with fat and sugar produced effects that cannot be completely replicated with only sugar or only fat, now worships the energy-balance dogma:

• [Joe Rogan 44m] When you are eating a sugary diet, a high-calorie diet, your body will get fatter, right? 
• [SG 44m] It depends on how many calories you are eating.

This is the same guy who believes that sugar can make you fat because it is palatable, regardless of how many calories it has. But when he is interested in showing support to the official dogmas, then he says that calories are what makes us gain fat. Guyenet is a master of cognitive dissonance. Or a master of decepcion who is betting to two horses at the same time.

There is no obesity if westernized food is not present

They both agree on that. It is clear, I would add, that it is not a dysfunction in the brain what causes obesity. An analogy can make this clear: if I prick someone with a needle and that person bleeds, the cause of the bleeding is not the lack of a band-aid: it’s been the needle prick what has caused the bleeding. Even if we know that a band-aid stops the bleeding. Speaking of obesity, if your genetic endowment is better than that from other people, maybe it protects you from «food» that you shouldn’t be eating, but what causes obesity in those other people is the insult, not their faulty brain: the cause is the stimulus, that is, what they are eating and they shouldn’t be eating.

Let’s see an example. Suppose we have two people (person A and person B) who are exposed to two different environmental conditions (conditions 1 and 2) for a time, with the following results in terms of body weight gain:

Person \ Environment	1	two
A	0 kg	+6 kg
B	0 kg	+7 kg

Even if we found a relationship between genetics and weight gain that explained the difference between those +6 and +7 kg, what is the real cause of the weight gain in this example? It is only an example, but it makes clear that although the differences between people’s fat mass under environment #2 can have a genetic explanation, not necessarily that fact tells us anything meaningful about the actual cause of their obesity.

On the other hand, Guyenet argues that there are populations that consume a lot of sugar and they are not obese. He will give details later in the debate. What I want to emphasize is that his counterargument does not prove anything about the reasons why we get fat in the western world, not even in case we believe the data of those populations are reliable. They just don’t live under the same conditions we do. For example, there could be a synergistic effect of sugar with seed oils (high omega-6) or with some endocrine disruptor, and finding out a population that has a high consumption of sugar and no obesity, in the absence of other factors typical of the western world, cannot be used to exonerate sugar in societies in which sugar coexists with a different set of dietary and environmental factors. Or maybe these people spend a lot of time outdoors (under the sun) and respect their circadian rhythms and that fact protects them in a certain way from sugar, and that is not our case. Or maybe those populations follow very low-fat diets in which sugar is not so harmful to their health. Who knows.

Obese mothers and undernourished children

The «double burden of obesity» is the coexistence of obesity and undernutrition in a population (see). For example, in the following graph we have BMI (body mass index) versus age in refugee camps in Western Sahara. As we can see, in all ages there are both people with clear obesity and people with very low BMI:

And in this study in a quarter of the households coexist obesity and malnutrition:

Our results demonstrate that both stunting (in children and women) and obesity (in women) are highly prevalent among Sahrawi refugees, with central obesity being even more prevalent and appearing at a younger age in women than obesity. Second, more households were affected by overweight and central obesity than by under-nutrition, although the latter affected over one-third of households. Third, an important proportion of refugee households, one in four, are affected by the double burden of malnutrition.

How do you explain that there is an obese mother who has an undernourished child? Guyenet puts into question the data provided by Taubes, that is, he says that a woman cannot gain weight by consuming only 1800 kcal/d.

[SG 1h0m] What Gary says is only observed when inferior methods are used to measure calorie intake

Is that so? Does the obese mother overeat while her child is starving? This is hard to believe.

[Joe Rogan 56m] You’re saying that by consuming low amounts of calories but high amounts of sugar, it does not make sense that one can become obese that way. 
[SG 56m] Correct.

Let’s mention four scientific experiments I have already commented in the blog. In the first one (see), we have a group of rats, the HS group that consumes a diet high in sugar. As we can see in the table below these lines, this groups consumes about 100 kcal/d, while the HF group consumes about 200 kcal/d. The body weight and body fat data tell us that the group that consumes 100 kcal/d finishes the experiment with more weight and more fat mass than the one that consumes 200 kcal/d. Can you get fat while eating too little? Yes, you can.

This is an experiment in animals and, therefore, absolutely controlled. There are no reasons to doubt caloric intake data in animal experiments.

The second experiment (see) shows that the same food, and therefore with the same calories, is much more fattening when consumed as powder than when consumed as pellets. The graph shows in pale pink the evolution of the body weight of three dietary groups that consume much fewer calories than the group represented with empty circles, and yet, the evolution of their body weight is practically the same as in that group:

This means that in this experiment, while eating much less food, those three groups of rats are gaining weight at the same rate as rats that consume more calories. I insist: in the experiments with animals the caloric intake is not poorly measured. The trick of questioning the reliability of the caloric intake is unwarranted here.

In the third experiment ( see ) the group of mice that eats the lowest amount of calories (white points) is the one that gains more weight and more body fat:

In the fourth experiment (see), the diet of the rats is identical in terms of nutrients and calories, differing only in their glycemic index. To prevent rats in the high-glycemic-index diet from gaining more weight than the other group, their intake had to be considerably reduced, as shown in the graph a the top:

Despite the reduced intake compared to the other group and despite having practically the same weight as they have, the high-glycemic group finished the experiment with 71% more body fat: 98 g vs 57 g. And they are eating less food:

[SG 54m] Gary, you seem to believe that people can gain weight even if they are eating too few calories …

Gary Taubes believes that it is possible what the  four scientific experiments above show is possible. The question is why Guyenet doesn’t think it is possible. Doesn’t Guyenet know what has been published in the scientific literature?

Anyway, I think Guyenet is entitled to doubt the data. What is unacceptable is the arrogance of saying that Taubes’ arguments are story-telling and of presuming that his own opinion is supported by scientific evidence.

Gary has told a story, his version of the Pima story. Let me tell you the version of the story that appears in the scientific literature.

As we will see in other segments of the debate, the «anecdotes» that Guyenet will use (the Kuna, the Cuban economic crisis or the Hadza) are observations that are quite similar to the cases explained by Taubes, i.e. the Pima, the Sioux and Trinidad. Story-telling or science in both cases, no matter who puts them on the table. Guyenet uses plenty of derogatory comments towards the Taubes’ arguments and presumes of being the defender of what the scientific evidence says. Why does Guyenet think he is better than Taubes? He is not even a researcher any more, in contrast with what he implies in the debate: he is a writer and a scientific consultant. Not only does he use the fallacy of authority, he does it by bragging about being what he isn’t.

People who suffer from obesity eat too much

I put together here three of Guyenet’s arguments:

• obese people eat between 20 and 35% more calories than lean people
• in the Guyenet model eating a lot is a requirement to gain weight
• if you reduce the intake in that same amount it does not matter if you do it by restricting carbohydrates or fat, the experiments say that you lose weight

The first point already appeared in the first segment, but I insist on it because I find it interesting. Gary Taubes argues in the debate that to develop obesity it is enough to accumulate 10 kcal/d, and that this is not explained by an «excessive» consumption, because of that «excessive» intake that there may be every day only 10 kcal/d end up being storead as body fat. As Guyenet cannot justify saying 10 ridiculous kcal/d are an «excess», what he does is redefine «excess» as the difference between what you eat when you are already obese and what a lean person eats. With this trick he converts those 10 kcal into a much larger amount, and this allows him to go on using the term «excess». In any case it is a rhetorical trick that he uses to avoid answering the question. And in doing so, he blames the victim for his weight problem: if you have obesity Guyenet says that you overeat even if you maintain your weight, even if you eat what your body asks or needs to function. We should not fall in his trap: we are not talking about the person who already has excess weight: the one who is gaining weight does so at a rate of 10 kcal/d. Does this accumulation of energy occur because this person eats 10 excess kcal/d compared to the person who does not gain fat? That is the question that Guyenet avoids to answer. Because nobody can accept that 10 kcal/d are an «excess». And maybe that fat accumulation is not produced by the «excess», but instead by the composition of the diet. Guyenet has beliefs, but he may be wrong in his beliefs.

Moreover, Guyenet uses this argument as an explanation for the «dual burden of obesity», but he is not using data from the populations cited by Taubes. He doesn’t know if that is the case of those populations.

The second argument is that an increased intake is a requirement to gain weight in Guyenet’s obesity model. Well, we have seen four scientific experiments that show that, in such a case, his model is wrong. And I find it very interesting that he uses the term «requirement», because precisely one of the errors on which his pseudoscience is based is to assume that an increased intake with respect to the energy expenditure is a requirement to gain weight. It is not!! That belief is based on errors of reasoning, and I have explained thousands of times in the blog (and we are near the point where saying a thousand times is not an exaggeration): see, see, see, see.

Finally, Guyenet says that by reducing the caloric intake people lose weight. Guyenet is deceiving the hundreds of thousands of people who have seen this debate.The scientific experiments show that people lose weight in the short term, but the lost weight is almost always regained in the long term, even when the energy restriction is maintained (see, see). That’s what the scientific evidence shows, not what Guyenet is telling. What’s more, he could ask Kevin Hall, PhD what happens when you try to make someone lose weight by applying that method (see, see). But hey, it’s no surprise that Guyenet deceives people with clearly wrong arguments. This has an explanation: this guy is Guyenet, PhD.

In regard to this, let’s remember an experiment (see , see) in which a group of mice is forced to eat only 66% of the calories consumed by the rest of the mice (who follow different diets). As we can see, after the initial drop in their body weight they gain weight.

Have those mice lost adherence to the caloric restriction? No. They have gained weight while eating a small amount of food.

NOTE: all the terminology of the energy paradigm is in question. It is not obvious that the term «excess» (or «caloric excess») can be used associated to body fat gain .

Go to the conclusions
Go to the fifth part
Go to the fourth part
Go to the third part
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