Can overeating be a cause of obesity?

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What is the meaning of “overeating”?

I would say it is not called overeating, unless we think there is a negative consequence. If we say it is “overeating”, we should be able to say it’s “too much” food, “beyond a desirable amount” of food, and you must do it frequently, because otherwise you are not supposed to get the negative output (e.g. getting fatter). There must be a negative consequence and we all could agree that the negative consequence is getting fatter (and maybe sicker). Therefore, as I see it, overeating means eating so much food that something detrimental happens to you.

Note: the term “overeating” assumes that food quantity causes fat accumulation. That is the reason why, IMO, talking about “overeating” is always an error.

Can “overeating” be a cause of obesity?

if we get fatter and heavier, more energy enters our body than leaves it. Overeating means we’re consuming more energy than we’re expending. It’s saying the same thing in a different way”. Gary Taubes

Overeating is the same as getting fatter. It can’t be a cause of getting fatter because they are two ways of saying the same thing. Having problems paying attention and sitting still in a seat doesn’t cause ADHD.

But still, some people think eating “too much” could be a cause of obesity. The question here is “too much, compared with what?“. People use to say “more than our needs”, but the reality is there is no such thing as “our needs”, i.e. a level of caloric intake beyond which we get fat. We only know if we are overeating if we get fat. Even if eating a diet with 2500 kcal/day your weight is stable, you can’t say a 3000 kcal/day diet is going to make you fatter. It could even make you leaner.

Blaming obesity on “eating more than was expended” is  incorrect because whether more was eaten than expended can’t be known unless the patient is already obese. Bill Lagakos

  • Why are you obese?
  • Because I overate
  • How do you know you overate?
  • Because I am obese

Unrealistically extreme situations don’t give answers about normal conditions

If a eat 3000 kcal/day of real food and I don’t get fatter, am I overeating?

If I eat 3000 kcal/day of fast food and I get fatter, am I overeating?

What do you think?

is it impossible to gain weight if you eat let’s say 500 grams of fat a day, on a real food, low-carb, high-fat diet? (see)

That would be 4500 kcal/day only from fat. That would be unusual and probably unnatural: you have to force yourself to eat that much. Therefore we are prone to think it may be harmful and/or fattening, and for that reason we are prone to say that that is “overeating”. Since we perceive that that is a forced situation, we probably could say that in that case overeating is probably causing obesity. But, is that a proof that “overeating” is a cause of obesity in normal people who don’t force themselves to eat for three? No, it isn’t. It just means that an unrealistically extreme amount of food is probably fattening. It doesn’t prove that a positive energy balance is a driver of obesity.

Even if driving you car in the city at 200 mph is a death sentence, that doesn’t prove that driving at a normal speed is dangerous. Talking about an unrealistically extreme case is moving the goalposts.

Whether you get fatter or not with a specific diet depends on the composition of the diet (see,see,see) and also on the physiological response of each person (see,see,see). Even if you are objectively eating “a lot”, it is still about the physiological stimuli you create with that food and about the physiological response of the person eating that food.

For a healthy person, eating a real food diet is probably not going to lead him/her to obesity. That is what we know from what has happened for millions of years to the human species and to other animals. It is eating crap what has made us obese and sick, not “eating too much” because of “food-reward”.

The right question isn’t why we eat so much, it is why are we getting fat. Talking about calories leads us to wrong causes and wrong solutions (see).

Reading further:

In nutrition science, the blind lead the blind

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Obesity is generally caused by eating too much and moving too little

If you want to lose weight, don’t eat. This is not medicine, it’s thermodynamics. If you take in more than you use, you store it.

The law of conservation of energy states that energy can’t disappear. What we eat, has to be transformed in other forms of energy. In simple terms, a person’s energy intake must be transformed into bigger muscles, more fat or will be spent as heat/work.


First mistake

The first mistake some “experts” make is to pretend that the above equation gives an explanation or the keys to understand how a system works. What do I mean? It’s very simple: in the above equation, do the terms on the left side of the equality sign depend on the terms on the right side of the sign? Do muscle development, fat accumulation and dissipated heat determine how much I eat? Mathematically, yes, they do, but this approach is stupid, as is obvious when we think about how every term of the equation behaves in the real world.

If you rearrange the terms of the equation, you will clearly see the origin of the first mistake “experts” make, to think that mathematics tell us what to do to control the accumulation of fat:


Does the equation above say that energy intake, energy expenditure and created muscle determine the amount of fat we store? Even if you think it makes sense, I remind you this is the same interpretation we talked about before, and it made absolutely no sense. From the formula of the conservation of energy it can’t be inferred that energy intake, energy expenditure and created muscle determine the accumulation of body fat. Whether the idea is correct or false, is a question to be answered from our knowledge of the how our body works, never inferred from the laws of thermodynamics.

Second mistake

The second mistake some “experts” make is omitting muscle building.


As I will discuss soon, some “experts” tell us that an excessive intake (“eating too much”) and a reduced energy expenditure (“moving too little”) make us store fat. They say that it follows from the laws of thermodynamics. Ok. In that case, I ask why eating too much and moving too little doesn’t lead us to an increase in our muscle mass, instead of increasing our body fat. What part of the above equation says gluttony and sedentarism lead to obesity but not to muscle building? Why is it that all the positive energy balance goes to one of the terms in the left side of the equality sing and not to the other term?

In order to blame the obese of being gluttonous and sedentary, the “experts” make “muscle building” disappear from the equation:


Third mistake

The third mistake the “experts” make is to ignore reality. The theory they think unquestionable is that energy intake is controllable, because it depends on how much we eat, and that energy expenditure is manageable, because they tell us that it basically depends on how much we move:


And the mistake of this theory is that it ignores all the scientific evidence that what we eat and how much we exercise, both of them influence energy expenditure and fat accumulation. In addition, exercise probably is going to make us hungry, and also losing/gaining weight will modulate our tendency to exercise. The theory “eat less and move more” is not consistent with our knowledge about how our body works:


(I’ve reverted again the order of terms in the equality, in order not to encourage the first mistake I pointed out, i.e. thinking that the terms on the right side of the equality sign determine the terms on the left side)

It is perfectly possible to increase the caloric intake, without more physical activity, and lose weight (see, see, see) or gain fat (see). And decreasing the caloric intake has never worked for losing weight (see) because our body reduces its energy expenditure making impossible to lose weight (see). And we can’t take for granted that after a intense physical activity, our body will spend the same energy as if we hadn’t done that physical activity (see). Neither can we assume that the total energy expenditure is independent of what we eat (see). None of the above are effects that can be ignored. Therefore, the third mistake is essentially assuming as true the following hypothesis:

  • What I eat only affects the caloric intake, and not the fat accumulation nor the total energy expenditure. That goes against the scientific evidence. E.g., if I decrease the intake, energy expenditure will be reduced much more than what the “experts” admit.
  • Energy expenditure is a term that only depends on exercise. That is contrary to the scientific evidence. E.g. our body can compensate in the following few hours the energy expenditure created through the physical activity. Another example is that the the specific content of the diet affects energy expenditure. It is different when the diet is based on carbohydrates and when it is based on fat.

Fourth mistake

The fourth mistake is in part the result of mistakes I exposed before, and it is to close the door to other possible causes of obesity. This one is the refusal to listen to other ideas, and later accept or discard them rationally. A not-too-smart “expert” can make all those three previous mistakes, but to rule out, just because, other points of view, is a new mistake. There are other approaches perfectly “consistent” with the laws of thermodynamics (see,see), but they are discarded arguing that anything apart from “eat less and move more” is stupid. A clear sign that the economic interest for continuing without listening is strong.

“Excessive intake” or “lack of exercise”. Those are the only options considered by some “experts” on the grounds that it they derive from the laws of thermodynamics. But, as we have seen, that way of thinking is the result of several thinking mistakes.

It is ridiculous to observe that when an experiment says “it is not an excessive intake,” then they conclude then “it must be lack of exercise.” And when the evidence says that “it is not a lack of exercise,” then they conclude that “the intake must have been excessive.”


Some “experts” in the nutrition field think a physical principle can be deduced from mathematics:


It is not true. Just as a causality can’t be inferred from a correlation, the above formula doesn’t tell us why we store fat and how to avoid that process. It is only a mathematical equality, something that must be fulfilled, nothing more than that. Change the order of the terms, so nobody would imagine that the accumulation of fat depends on what is on the right side of the equation. Add the term of muscle building. And do not confuse energy expenditure with exercise, and neither ignore that what you eat and your physical activity affect all the terms of the equation. Look at the equation again:


Do you see in that mathematical expression any reason to blame the obese for having earned it all by themselves, because they are lazy and gluttonous? That accusation is not based on the laws of thermodynamics, but rather on the ideology of those “experts”. It’s a sign of arrogance. Since it is an idea that is not derived from the laws of thermodynamics, the question is, what evidence do these “experts” have that gluttony and sloth are the causes of obesity, and not, conversely, a consequence of a diet based on the consumption of grains, flours and sugars? That is, what evidence do they have that proves that those “experts” and their absurd dietary recommendations haven’t caused the obesity epidemic? I don’t think they are in a position to blame others for anything. A diet based on flour (grains), sugars and seed oils, or exposure to certain toxics (see), could change our metabolism, leading it to a fat storage mode. That dietary change would end up making us eat more than we spend. If anyone thinks that this hypothesis is not consistent with thermodynamics’ laws, he/she is committing several thinking errors.

Let’s think about gluttony and sloth. If for every two obese men there are three obese women, are the “experts” saying that women are lazier and more gluttonous than men? Seriously? And poor people are lazier and more gluttonous than wealthier people?

Just one more thing: do you think that children grow up because they ingest more calories than they spend? Do you think they stop growing up when their parents decide that they have grown up enough and stop overfeeding their children? Do you think that that idea derives from the laws of thermodynamics?

Further reading:

The dumbest thing ever

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There is a dogma in the nutrition field that says “fat accumulation is determined by the difference between the calories you eat and the calories you burn, no matter the source of those calories.”  In a more concise way, it is said that for losing weight or becoming fat “all that matters is the energy balance” and that “a calorie is a calorie”.

Other people, like me, however, think that this dogma is false and that counting calories is nonsense, as absurd as adding apples and oranges. 400 kcal of sugar don’t have the same effect on our body as 400 kcal of butter. They do produce the same heat in a calorimeter, but they do not cause the same effect on a human being. That makes sense, right? This point of view raises the ire of some people, and we are accused of denying the laws of thermodynamics. They are physical laws of the universe! I’ve come to read (see the first note at end of the document), and they call us zealots for denying the compliance with these laws (which we don’t).

I am aware that those from outside the world of nutrition live in deception. If you haven’t spent some of your time on this field, if you haven’t spent a minute of your life thinking about what calories are, most likely you still think that the dogma is true. No surprise there. I’ve been in that situation and don’t consider myself an idiot because of believing that. I never questioned the dogma.

But a different case is to hear nutrition experts say that advantages (real or not) of a diet like mine, like producing greater weight loss with the same amount of calories as other diets, “are not compatible with the laws of thermodynamics. ” Well, that, coming from alleged experts in nutrition, is really serious, as it is assumed that these people have indeed spent a couple of minutes thinking about it. If these people really are honest when they talk about “incompatibility”, when they realized the extent of their mistake, they surely would want to disappear from the face of earth. Or delete entries from their blog, as one of them is used to do.

It’s really very simple. In a very very simplified way, the energy expended is derived from ingested food and burnt body fat:

What I spend = what I eat + the fat I burn

Let’s say a person normally spends 2500 kcal per day and today he/she ingested 3000 kcal. The dogma says that there are 500 kcal/day that will make you fat. And according to the dogma:

2500 = 3000 + (-500)

where the negative sign means that we gained body fat instead of burning it. Very important: the first law of thermodynamics says that the sum of the blue and green terms must be equal to the red term. The equality must be fulfilled. Something that is true in this case, and therefore this energy partition is possible, because it doesn’t violate the law. Simple, right?

Okay, now I suggest that those excess 500 kcal can change the total energy expenditure of that person, increasing it by the same amount, 500 kcal, (the excess is lost in the form of an additional heating of the body) and therefore there will be no fat accumulation.

3000 = 3000 + 0

Are the laws of thermodynamics violated here? No, the sum of the blue and green terms is equal to the red term. There is no violation of the laws of thermodynamics. This second energy partition is also possible, because it doesn’t violate these laws, either.

In summary, the idea is that these “extra” calories can not disappear, they surely have to go somewhere (so says the first law of thermodynamics), but thermodynamics don’t tell you where they go, to body fat or to an increase in energy loss as body heat.

And what determines if the fate of that “overeating” (if such a thing does exist) is to be converted into body fat or to be lost as heat? That is, what determines whether excess food will make us fat or not?

The first law of thermodynamics is not going to give you an answer for that.

Let’s say I propose that “the composition of the diet, not calories, is key in determining whether you lose or gain body fat”. What is important right now, in this little dissertation, is not to know whether this statement is true or false, but to understand that it is possible! and that in no way implies a violation of the laws of thermodynamics. The laws of thermodynamics only say that the mathematical equality we’ve seen before must be fulfilled, but they don’t impose a specific value for the terms of the equation. When you use a diet A you can be accumulating fat, while another diet (with exactly the same total calories) can cause the excess calories to be lost as heat. In both cases the equality is fulfilled. In both cases the laws of thermodynamics are satisfied.

Perhaps with diet A we have: 2500 = 3000 + (-500)

and with diet B we have: 3000 = 3000 + 0

Both diets have the same total calories, and gaining body fat, or losing it, may depend on what you eat. It’s simple to understand, right?

Well, from now on, whenever you read that “Food A is not more fattening than Food B because it has the same amount of calories”, you will see it like I do, and you will stop reading what that person wrote or listening to what they say, because you will know they are ignorants. Now you understand that counting calories is meaningless. Why would you care about the total calories of a the diet if you don’t know where those calories will be used? The total calories of food, if you don’t know about the energy partition your body is going to apply, provide no useful information to you.

And when you read sentences like these (they come from two different people):

“I believe that the truth is far simpler and far more compatible with the laws of thermodynamics ”

“the insulin hypothesis is not consistent with basic thermodynamics”

you will wonder, as I do, how can a person who is professionally involved in the nutrition field have a misconception as profound as that, something that is so obvious and that only takes five minutes to understand it?

Just one more thing: the dogma that “fat accumulation is determined by the total calories you ingest, and not by diet composition” is false, as has been proved in many scientific experiments. For example, the experiments I explain in the pages linked below this line are impossible according to the Calories In Calories Out dogma. The experiments are real or the CICO dogma is true, but both can’t stand at the same time. If a theory is contradicted by the scientific evidence, it is false.

I wrote about these ideas a while ago (), but when I read another comment about the “incompatibility” with thermodynamics, this time coming from a vegetarian, one of those who go through life giving lessons to us, it seemed to me it was time to write again about it.

Further reading::

NOTE: The page that says we are violating laws of the universe has been removed . The URL was:

But the author published it here too:

It’s quite simple. If you have a caloric deficit, you lose weight. If caloric balance is positive, you gain weight. Energy balance is a direct representation of the first law of thermodynamics, the one that says energy can neither be created nor destroyed. We’re not talking about a hypothesis here, or even a theory, but a physical LAW OF THE UNIVERSE. Ever hear of the law of gravity? A law is something scientists are so damn sure of there is no disputing it. You can’t deny the first law of thermodynamics any more than you can deny the fact that if you jump out of a high-flying airplane without a parachute, gravity will not be your friend. (Note to fans of The Secret: the “Law of Attraction” is not a real scientific law.)

And yes, I do know there are bestselling low-carb authors who question this law. They present themselves as “controversial.” They assert that years of accepted science is wrong. Let me ask you a question: The next time you get into an airplane, would you rather it was designed, built and tested in a scientifically proven manner, or a controversial one?

NOTE: I have tried to simplify the explanation as much as possible, even at the risk of committing inaccuracies. The false dogma of “energy balance” is a simple idea (even the dumbest person understands it) and to prove it is false it seemed fit to also use simple explanations.


Calories don’t count

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Do calories count?

In one word: NO.

But that question is tricky. What does “count” mean? Count, for what? Speaking of what? Calories from what?

Does the law of gravity count for walking? Of course it does: without gravity it wouldn’t be possible to walk. But, do you need to know that fact to be able to walk? If someone told you that without understanding the law of gravity you can’t walk, would he/she be right? If someone told you that when you walk your body exerts a force upwards exactly equal in magnitude to the force that gravity exerts downwards, does that fact help you at all? The law of gravity doesn’t count for walking. Although it is essential to walk and it always applies.

The same happens to calories: they don’t count because they do add nothing to the main questions in nutrition, being those how to eat well and be healthy.

Do calories count when chosing what to eat?

No. Thinking about calories leads to the wrong decisions about what to eat (see).

Do calories count when trying to lose weight?

NO. Thinking in terms of calories can lead us to think that “eat less and move more” is an appropriate strategy for weight loss. And for most people it is not (see).

Does the energy balance count for weight loss (losing fat)?

NO, because the energy balance will always be satisfied, wether we get fatter or lose weight. The key to a successful weight loss is not changing the total amount of calories ingested nor changing our physical activity, but understanding:

  • How to lose body fat in the long term
  • How to avoid the undesirable changes in the metabolism and the hormonal response that often happen in the long-term

If we find the key to understanding those two aspects, the terms of the energy balance will reflect our success (see). The key to success is understanding how our metabolism works, not counting calories.

If calories don’t count, can I eat as much as I want?

I didn’t say that. What I say is that if you think in terms of calories you will probably end up eating too much and gaining weight. When you eat the right foods overeating is unlikely and possibly “harmless”. On the contrary, if you eat the wrong foods, you will probably overeat and get fat. May be you think that is the same as saying that calories count, but it is not. My point is that:

  • the foods you chose to eat are what really matters , and that
  • thinking in terms of calories is counterproductive because it leads to the wrong choice about what to eat.

Even accepting that there are people who can’t avoid overeating on a healthy diet, their problem would be eating too much food, not eating too many calories. No need to talk about calories, and since thinking in terms of calories is counterproductive, we should stop talking about them.

Many sensible people say “calories do count” and I think what they actually mean is that “gravity applies”. Saying “calories don’t count” is not a denial of universal laws, just saying that to think of them gives us nothing useful. I think the key to eating healthy, and keeping the weight I lost one year ago, has nothing to do with calories: calories don’t matter.

Biology determines calories

Read it again, because that’s the key idea: our biology determines the calories. Trying to change the terms of the energy balance doesn’t work because there are terms that are not under the control of the rider, but under the control of the elephant ( see , see ). If you want the elephant to behave in a certain way, you have to understand how it works, you have to pay attention to its reactions. Don’t ignore how it behaves when you restrict the amount of food. Don’t ignore how it reacts when you exercise (see,see). If you believe that nutrition is more a matter of mathematics rather than biology (see), you are denying the existence of the elephant. And even if you ignore its existence, it is there.

But if I eat less calories than those I spend, I will lose weight!

Are you sure of that? In the long term? Why do you ignore the overwhelming scientific evidence that says that caloric restriction and exercise do NOT work for long-term weight loss? Hundreds of scientific studies say that is not true  (see,see)

Moreover, forget the scientific evidence. Do you see people around you lose weight in the long term just doing that? Do you really think that the method works but no one follows it?

When riding a bike…

Do calories matter? No, they don’t matter. For what they are used, which is to decide what to eat, calories don’t matter.

Another analogy: when you ride a bike, unless the forces you suffer sideways are balanced, you will fall down. If one is greater than the other, you fall down. Is that important? No. It needs to be so not to fall down, but it adds nothing to our knowledge of how to ride a bike. Does any father tell their children that forces must be balanced for not falling down? Saying that it doesn’t matter is not the same as denying that those forces must be balanced. A useful tip may be to know that the speed of the bicycle helps to achieve the balance of those forces. Just thinking about the balance the forces, doesn’t help us at all. Eat well, make your bike move, and calories, forces, will get in their place. If you ride thinking about balancing the forces, you’ll end up kissing the ground. If you eat thinking about calories, you will end up obese and suffering health problems.

What mice tell us

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We hear from the obesity experts that “if we create a caloric deficit, according to the laws of thermodynamics we will lose weight.” Since the laws of thermodynamics always apply, the scientific demonstration that a caloric deficit doesn’t work to lose weight (see), leaves us with no doubts:

The idea that to lose weight you have to eat less and move more is NOT backed up by the laws of thermodynamics

It’s as simple as that: if it derived from such laws, it should always work. But it doesn’t work, therefore it is not a logical consequence of such laws.

The dogma “eat less and move more” is wrong and absurd. And from the moment some people “thought” that this dogma was the direct incarnation of those laws, any alternative proposal is said to be contrary to the laws of thermodynamics, and therefore wrong.

Another way to demonstrate that the theory of energy balance is not a corollary of the laws of thermodynamics is finding other theories, different from the “energy balance” theory, that also satisfy the laws of thermodynamics. A few days ago I published an article (“Thermodynamics for dummies “) exemplifying exactly that: how alternative explanations of how you lose or gain weight are perfectly compatible with the first law of thermodynamics. But please note that the fact that a theory satisfies those laws doesn’t mean it’s right, neither that it is useful. “Eat less and move more” is an example of that: it is compatible with the laws of thermodynamics, but it has been proven false. I think it is also counterproductive for human health (see).

The laws of thermodynamics can’t be used to predict the behavior of a complex living organism, it just tells properties of such behavior. It is the physiology of the living organism what determines its evolution. For example, Gary Taubes in one of his videos shows two photographs of the same child at different ages and with different body weight. The first law of thermodynamics can tell us that if you’ve gained weight, then you ate more than you spent. But it can’t explain why the child grew up. Knowledge of how our body works (e.g. the hormones) can help with that, but thermodynamics’s laws can’t. Thermodynamics only tell us that no matter waht happens, and regardless of why it happens, the behavior will fulfill certain conditions. It can’t predict the outcome, nor show us a way to change the process.

The study

There is a very interesting 2007 study named “A high-fat, ketogenic diet you induce unique metabolic state in mice “. I don’t use to give much importance to animal studies, but in this case there is no reason to ignore them: the laws of thermodynamics are always met, also in animals. If the laws of thermodynamics had something to say in nutrition, they should predict the weight evolution of any animal. At the end of the day what the “experts” tell us is that physiology doesn’t count and that gaining or losing weight is a simple matter of eating more or less. Mouse or person, if you eat more you will gain more weight. Mouse or person, if you eat the same amount of food you will gain the same amount of fat.

Mice are divided in four groups, with four different diets. Three of these diets are shown in the table:

Diet Fat (%) Protein (%) Carbohydrates (%)
(C) chow 16.7 26.8 56.4 (6.5% sucrose);
(HF) High in fat and carbohydrates 45 24 35 (17% sucrose)
(KD) Ketogenic 95 5 0% (0% sucrose)

The fourth diet (CR) is restricted in calories and provides only 66% of the normal caloric intake of those small animals.

Mice are allowed to eat ad libitum (i.e. they eat as much as they want to) for two months (except the CR group, for which the amount is restricted). The 3 ad libitum groups (C, HF and KD) eating more or less the same amount (in calories). Caloric intake of the CR group is shown with white circles:


The “Calories In Calories Out” paradigm tells us that those mice that eat a 66% of the intake of the rest (CR group) must end up with less weight than mice from other groups, while the three other groups (HF, KD and C) must end up roughly equal in weight.

“Those who eat less should end up weighing less …”

The reality is that the “Calories In Calories Out” paradigm is wrong: after two months there was no difference in the weight of the ketogenic group (KD, black triangles in the graph) and the calorie-restricted group (CR, circles and discontinuous line). And remember that the CR group had consumed 66% of the calories consumed by the KD group. Very different caloric intake, the same weight result.


How can that be? Are mice violating the laws of thermodynamics? No, they don’t. As I explained elsewhere, thermodynamics doesn’t say that mice who eat much more must end up weighing more. This erroneous deduction is not derived from the laws of thermodynamics. What thermodynamics say is that if even after eating more you end up with the same weight, that means you expend more energy. And so it was. Analysis of heat from the animals revealed that for the KD group energy expenditure was a 15% greater than for the CR group (and 11% higher than the C group). That is, the mice following the ketogenic diet “generated” more heat: they had a higher metabolism than mice with other diets. For example, the 24h measured heat was clearly greater than in the other groups:

And indeed, there were no differences in body composition (body fat mass, and lean mass) between the CR and KD groups. It is also interesting to know that the KD mice showed much lower levels of postprandial insulin, compared to the other groups of mice. A final curiosity: in one study, female mice of the CR group stopped having the menstrual cycle, something that did not happen in the KD group.

A second experiment, from same study. Now for 84 days all mice get fatter and fatter with the HF diet (high in carbohydrates and fat). At that moment, a part of them is moved to the KD (ketogenic) diet. The output? The KD group’s mice lost weight and ended up with even less body weight than mice in the control group. Those who followed the HF diet never stopped gaining weight.

“To lose weight you have to eat less and move more” …

The “Calories In Calories Out” paradigm tells us that to lose weight you have to eat less and move more. Is that what happened in the experiment? Did mice ate less became of the ketogenic diet? No, they continued eating roughly the same amount than before (after the change of diet a little less, then a little more and once the weight stabilized, the same). So how is it possible? Again, mice from the KD group generated 15% more heat than the HF group, and their oxygen consumption (another indicator of the energy expenditure of the mice) was 34% higher than in the HF group.


A few more results:

  • Mice in KD group ended up with virtually the same amount of body fat than those from the control group. The HF group ended up with more than twice as much fat as both groups. KD mice didn’t lose muscle mass.
  • The KD group passed a glucose test with better results than the HF group.
  • In the HF group “exploratory activity” was reduced, but not in the KD group. It could be said that getting fat made them more sedentary.

Eating the same amount resulted in very differently output in terms of weight (and health). The laws of thermodynamics are always fullfilled, what doesn’t are the “theories of energy balance”, i.e. the “eat less and move more”, counting calories, “eat everything but in moderation” and “you are fat because you’re a sloth and a glutton”.

The authors conclude:

By specific dietary manipulation, weight loss may occur as a result of various metabolic changes without restricting calories.

Losing weight without eating less and without reducing your metabolism … All this reminds me of the Sam Feltham‘s experiment (who, by the way, recently published a book ).

Thermodynamics, for dummies

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First law of thermodynamics

It is the principle of conservation of energy. Applied to nutrition:

Energy Expenditure = What I eat + The Fat I Burn + The Muscle I Lose

The energy I spend comes from what I eat plus the fat/muscle I “lose”.


The grain diet (perfect for fattening the cattle)

Let’s say a man keeps his weight and body fat stable consuming 2000 calories / day:

Energy Expenditure = What I eat + The Fat I Burn + The Muscle I Lose

2000 = 2000 + 0 + 0

What happens if this person decides to follow the grain diet (i.e. living on bread, grains, pasta, pizza, etc.)? All these carbohydrates will skyrocket his blood glucose levels, and therefore also the insulin. Insulin gives a command to the adipocytes (fat cells) that they must store fat. Let’s suppose that from the total calories this person eats each day, 200 are stored as fat. Our organism has 200 Calories less available and therefore must adjust accordingly the energy expenditure and the food intake. The terms in red and blue must change to cope with this change:

???? = ???? + (-200) + 0

On the one hand the body forces the person to reduce his energy expenditure, for example making him more sedentary. A reduction from 2000 to 1900 Calories in energy expenditure. But he also needs to eat more to compensate for the Calories that are stored as fat instead of being used as fuel. That person goes from an energy intake of 2000 calories to 2100 calories.

1900 = 2100 + (-200) + 0

And day after day that person is storing a little bit more fat … not because he is sedentary and gluttonous, but because of an excess of carbohydrates in his diet. A sedentary lifestyle and an excessive appetite are consequences of being fat. And he becomes fat because of his bad food choices.

Trying to lose weight with calorie restriction (and failing)

Again, let’s say a person keeps stable his body fat consuming 2000 Calories/day:

Energy Expenditure = What I eat + The Fat I Burn + The Muscle I Lose

2000 = 2000 + 0 + 0

He burns 2000 Calories per day, which is the same amount he ingests. Now that person decides to lose weight by eating less: only 1500 Calories/day. The very first days of this new diet the energy expenditure is still 2000 calories, so his body is forced to burn fat and muscle:

2000 = 1500 + 300 + 200

As time goes by, his body reacts to the food restriction by cutting the energy expenditure. Now he spends 1500 Calories/day, the same amount he ingests and he stops burning fat:

1500 = 1500 + 0 + 0

But energy expenditure lows further to 1400 calories, and he begins to accumulate as fat those calories that are not used:

1400 = 1500 + (-100) + 0

There has been fat burning, but only temporarily. Soon he regains the lost weight. He ends up with more fat and less muscle than before. And always hungry.

Lose weight with carbohydrate restriction

As we did before, we start with a person who doesn’t burn fat:

Energy Expenditure = What I eat + The Fat I Burn + The Muscle I Lose

2000 = 2000 + 0 + 0

We restrict carbohydrates, which makes blood insulin levels fall and our body begins to burn fat. Suppose that now our body has suddenly 500 extra Calories, those coming from the body fat, and our body has to find a way of getting rid of them!

???? = ???? + 500 + 0

Our body has to change the terms in red and blue to accommodate those 500 calories:

  • a) it increases our energy expenditure, it “gives usmore energy”, urging us to move more, and increases the body temperature, and
  • b) reduces hunger with the aim of lowering the caloric intake, since it already has some calories from fat and there is no need to eat as much as before:

2250 = 1750 + 500 + 0

Thus, the person ends up burning fat (500 calories), with more energy (2250 Calories) and eating more than people on other diets (1750 calories intake compared to 1500 of those trying to lose weight by “eating less”, plus 500 Calories from fat). The 1750 Calorie intake may seem like a “calorie reduction” because this guy started with 2000, but it is not, since there are 500 Calories more from fat. In total the organism receives 2250 calories, so there is no “caloric restriction”. Our body does not feel under attack, it does not miss food (rather the opposite) and it will not react by reducing the metabolism. This situation is sustainable in the long term, which can allow us to lose weight significantly.

Thoughts on the irrelevance of appetite and calories

Some people believe that diets low in carbohydrates are useful to lose weight because fats/proteins have the effect of reducing the appetite and therefore the caloric intake. Decreased appetite causes reduced intake, reduced intake causes weight loss. It is an erroneous reasoning, based on the erroneous theory “Calories In Calories Out” (see). The reality is that, as we have seen, eating less with low-carb diets is a consequence of burning fat, not its cause.

The official dogma tells us many ways to control our appetite, as if it was true that not eating or eating less would lead to losing weight. Focusing on appetite control is focusing on caloric restriction, and that does NOT work to lose weight. To lose weight you have to focus on what you eat, not on how much you eat. If you count calories, you end up choosing foods that make you obese (see): counting calories is not just useless, it’s worse than that, it is counterproductive.

Eat so you activate fat burning. When you burn fat your body has “extra calories” to get rid of. How is it going to do that? It’s not your problem, nor should you worry about that. Do you need to count how many times you breathe per day to do it right?

Maybe all this seems like science fiction. It seems to me that fits well with scientifically proven facts, e.g. that caloric restriction diets do not work (see), and diets low in carbohydrates make people lose more weight than other diets, even when eating the same amount of calories (see), they do not reduce energy expenditure as much as other diets (see) and they naturally reduce the appetite (see).

Low-carbers say they feel more energetic throughout the day ( see ), and with a constant supply of energy, without ups and downs, and they also say that on this diet they notice their body warmer (seesee) . And I’m not talking about the different thermic effect of the food we eat, but of the effect caused by burning fat.

I recommend the graphic explanations of Lindha about the laws of thermodynamics.