The Failure of the Calorie Theory of Obesity

The calorie theory of obesity has been perhaps one of the greatest failures in the history of medicine. Given the number of excess deaths caused by metabolic syndrome, you could argue that it is a bigger disaster than World War II. It is based on a com

plete misinterpretation of the energy balance equation.

Body fat gained = Calories In – Calories Out

This equation, known as the energy balance equation is always true. So, looking at this equation, people then say something like ‘It’s all about restricting the calories you eat’, or ‘All diets work by restricting calories’. On the Calories Out side, you hear things like ‘You should exercise more’. This is the standard Eat Less, Move More approach. Doctors, even so-called ‘obesity experts’ and various health professionals say stuff like this all the time, but they’re completely wrong. The problem is that they don’t even know why they’re so wrong.

The energy balance equation (which, yes, is always true) does NOT support the Eat Less, Move More approach. Huh? Let me explain. You can also watch my recent video from NBC here.

Let’s throw some numbers into the mix to make things more clear. Let us assume the baseline situation of stable body weight (zero body fat gained or lost) and 2000 calories per day intake.

0 Body Fat = 2000 Calories In – 2000 Calories Out

Calories Out is not just exercise. This is composed of 2 things – resting energy expenditure, or basal metabolic rate (BMR) and exercise. If you assume zero exercise, an average BMR is 2000 calories per day. This energy is used by the heart, lungs, kidneys, generation of body heat etc. Note that BMR is NOT under conscious control. You cannot ‘decide’ that your heart will pump more blood. You cannot ‘decide’ to generate more body heat. No amount of willpower will make your kidneys use more energy.

Exercise is generally a very small portion of the total daily expenditure, unless you are exercising multiple hours in the day. Consider a moderate exercise of 1 hour of moderate walking/ jogging, 3 times per week.  Each walk burns approximately 100-200 calories. If you’ve ever exercised on a treadmill with a calorie counter, you’ll know how slowly that meter rises. That 100 calories used during exercise pales in comparison to the 2000 calories eaten on an average day. So, we can safely ignore the effect of exercise except for those who do in excess of 1 hour per day.

So, people suppose that if you decrease your caloric intake by 500 calories per day or 3500 calories per week, that you will lose 1 pound of fat per week assuming that 1 pound of fat contains roughly 3500 calories.

-500 calories = 1500 Calories In – 2000 Calories Out

Please take careful note that in order to lose body fat, Calories Out MUST remain stable. Must. Must. But this is precisely what we know to be FALSE for at least the last 100 years. BMR may increase or decrease 30-40%. This was shown as early as 1917, when studies showed that a reduction of calorie intake by 30% is quickly met by a decrease in BMR by 30%.

Dr. Ancel Keys showed much the same effect in his famous Minnesota ‘starvation study’. Despite the title, subjects were given 1570 calories per day, more than most weight loss regimens being prescribed today. A drop in calories eaten by 40% is met with a 40% drop in BMR.

The reason for this is simple. Your body is very smart and does not want to die. If you do not alter your hormones (predominantly insulin), you won’t be able to access your fat stores. If you can’t get energy from body fat, then then you cannot run an energy deficit forever. If you are only taking in 1500 calories, you can only spend 1500 calories.

So BMR drops. We’ve known this for over a century. If you cut a few calories every day, your body will burn less calories and you will not lose fat. Weight loss plateaus and then you start to regain weight. So, counting calories, as a strategy for weight loss, has been proven over and over again to fail.

Strategies that lower insulin, however (Low Carb, Intermittent Fasting) are completely different. By lowering insulin, we tell our bodies that there is no food coming in. Therefore, the body switches from burning the calories from food, to burning the calories from our body fat. Our body wants to burn 2000 calories, but it just gets them from body fat instead of food. Instead of restricting energy (calories), our body is switching fuel sources, from food to stored food (body fat). But this can only happen if we correct the underlying hormonal problem of excessive insulin. So is ‘Calories In Calories Out’ totally useless? Well not totally.

You may have heard of or received an email offer for the Nigerian Phishing (email fraud) scam. The story goes like this. A few years ago, some crooks would send out millions of emails to potential marks (victims). The emails would say that they were an exiled Nigerian prince that was forced to flee out of his home country. He had $10 kajillion dollars in the bank and offered to split it with you if you would only give him your banking information. In other scams, the crooks would ask for money. Send them $1000 dollars and then they could go to the bank, retrieve their $10 billion and give you $2 billion as a thank you. The scam became well known as a fraud and most people recognized it immediately so they simply deleted the email.

However, contrary to what you might expect, the scam did not disappear. I still receive these emails on a regular basis, and they even keep the Nigerian prince rather than change it to, for example, an Indonesian princess. Since almost everybody has heard of this scam, what was the point?

Crooks could immediately identify potential marks by sending out this particular scam. If the crooks made up a new scam, they would receive many replies to their email, but most of them would not be gullible enough to hand over actual cash. By keeping the Nigerian prince scam, they could immediately and efficiently identify the most gullible people who would hand over cash. In this way, the Nigerian prince scam is a great marker for gullibility.

The Calories In/ Calories Out (CICO) model performs the same task for me. The CICO model has been tested over and over again. Multiple trials have shown it to be a complete failure. If somebody vociferously defends the CICO paradigm, I can immediately and efficiently identify them as people who have not really understood what causes obesity, and have no serious grasp of the physiology behind weight gain. These are the people who keep parroting ‘A calorie is a calorie’, as if I had asked them ‘Is a calorie a calorie’? The question I ask is ‘Are all calories equally fattening’, to which they usually stare blankly at me, before replying ‘It’s all about calories’, as if the body had any actual method of measuring calories.

The CICO model very useful because it efficiently flags idiots people who are not all that knowledgable about obesity, and I can safely ignore them. There are many of these people out there, and not everybody is worth listening to.

2018-05-01T12:08:52+00:0030 Comments

About the Author:

Dr. Fung is a Toronto based kidney specialist, having graduated from the University of Toronto and finishing his medical specialty at the University of California, Los Angeles in 2001. He is the author of the bestsellers ‘The Obesity Code’ and ‘The Complete Guide to Fasting’. He has pioneered the use of therapeutic fasting for weight loss and type 2 diabetes reversal in his IDM clinic.

30
Leave a Reply

avatar
15 Comment threads
15 Thread replies
11 Followers
 
Most reacted comment
Hottest comment thread
23 Comment authors
SaraMichael SantosMike SantosChuckskr k aravindan Recent comment authors
  Subscribe  
newest oldest most voted
Notify of
ghanshyam Singh rathore
Guest
ghanshyam Singh rathore

Still mostly docs and so called nutritionists stick on CICO that’s why obesity is spreading as epidemic.

Chucks
Guest
Chucks

You’re making this sound like being not-explodingly fat is somehow rocket science here.

While the exactly science and finer points of optimizing bodyfat in the most beneficial and easiest to adhere to ways are being refined, I find it really hard to believe that CICO is somehow to blame for rising obesity.

Curious
Guest
Curious

If I have to lose weight, and have a BMR of around 2000kcal, I can eat Low Carb / do IF and not care about calories ? If I eat above my BMR (say 2500kcal), I doubt I will lose weight.

BobM
Guest
BobM

I am fasting two days this week, around 36-38 hours each time. For instance, I ate Sunday evening then ate again Tuesday morning shortly after 9am (about 36 hours), but after my workout with weights and HIIT, and getting to work. (By the way, I had a great, intense workout.) I did not eat again until yesterday at dinner, around 6:30pm. I was not hungry until dinner. Intermittent fasting, over time, does something to you that’s outside that equation Dr. Fung shows above. It changes you physically, such as modifying your hormones. The equation above does not take any of… Read more »

Curious
Guest
Curious

Because by not eating during 36-38 hours, you are limiting calories…

Richard
Guest
Richard

Curious: Hahaha, good joke. I mean, I assume you are joking… As Dr. Fung points out, the CI=CO “equation” is accurate, but the idea of weight loss is embodied in the variability and ability to control the hormonal (mainly insulin) aspect of the metabolism (BMR) itself, not in the voluntary and/or direct reduction of “calories” consumed. (The body does not “know” or detect how much you eat, in terms of calories, and sugar calories are not equal to protein calories.) The idea of weight loss is thus controlled indirectly by the timing of meals/eating (voluntary acts) rather than directly by… Read more »

Curious
Guest
Curious

That is not what the science says. By limiting meals / having prolonged fasting periods, you’re limiting calories. You also manage your insulin, but it is not what causes the weight loss.
Have a look at the latest NuSi study. Have a look at the potato diet. Even with carbs (and quite a lot), even with 3 meals/day, you can lose weight. And you can gain weight without carbs.

Stephen Nelson
Guest
Stephen Nelson

So Curious, as proof that “that is not what the science says” you point to one study that showed an increase in EE on the keto diet, even with the following limitations noted by the researchers:

1. no control group
2. unexpected weight loss on both diets
3. metabolic chamber malfunctions
4. did not test reverse order of diets, only tested BD followed by KD
5. duration of only 4 weeks on each diet

Richard
Guest
Richard

Curious: Again, I have to suggest that you can’t be serious. Except in one sense: You seriously want to discredit the approach to weight loss and Diabetes 2 control that Dr. Fung recommends, and his basis for the recommendations he has made. However, instead of questioning the citations and studies Dr. Fung has used to support his approach, you introduce entirely new information. That seems more like deflection than rational argument. Quite interesting to me is your motivation for making such an argument on this forum. One tenet of the approach used by Dr. Fung regarding these claims of “diet”… Read more »

Jim
Guest
Jim

Sometimes the calories in calories out people will complain about feeling cold when trying a CICO diet. But they will not put two and two together.

Matt Evans
Guest
Matt Evans

Hi Jason, I appreciate the ways you’ve highlighted fasting, but respectfully dispute the claims you make here against the caloric theory. The strongest evidence of the caloric theory is the strong success of various gastric band/bypass surgeries, which work solely by limiting caloric intake. These procedures reduce the size of the stomach to make patients feel full with less food, causing them to consume fewer calories. Lap band and bypass patients are not instructed to avoid carbs or protein, or to concern themselves about an insulin response. They are not instructed to alter their macros at all. They are not… Read more »

Stephen Nelson
Guest
Stephen Nelson

Matt, you are disregarding the impact that LGBS has on insulin resistance. This study https://www.sciencedaily.com/releases/2007/05/070501075127.htm showed a 60 percent decrease six months post surgery. This is completely in line with Dr. Fung’s statements about the impact of insulin in fat storage. You may say that patients are not instructed to change their macros, but observing how they actually eat after this surgery is informative. Among the people I know that have had LGBS, I see them focus on eating higher quality foods, like meat and vegetables, and avoiding the garbage foods like soda and chips because they have limited intake… Read more »

Michael Santos
Guest
Michael Santos

Nobody can eat fictitious entities such as calories or inverse fermions. They do not exist. You eat nutrients and CARBON ATOMS.

Sara
Guest
Sara

One issue I even have with Dr. Fung is that gastric bypass DOES NOT, keep people from getting stuck. One need only look at Roseanne. She is not exactly thin. Nor is John Goodman. Anyone who watches my 600 lbs life will see that typically the dieters do NOT get down to “thin”. Typically they might get down to 200 or 220. That is better than 600 but not thin. This is analogous to the rest of us getting stuck 20 lbs before goal. The thing about gastric bypass is that it is hard to gain it back because they… Read more »

Laguna
Guest
Laguna

Trial and error proves this to be true for me. Today is the 3rd day of a planned 72 hour water fast, and I did one last week. I’m dropping weight finally. If calorie reduction worked, I’d be skinny! In years past, I’d lose 20 lbs. and then stop losing weight even if I reduced calories further. Two weeks ago went back to the doctor who diagnosed insulin resistance, not on my current insurance. He had prescribed Metformin, which caused abdominal pain, so I quit. Switched insurance, so had not seen him for years, blood sugar has stayed just below… Read more »

William L. Wilson, M.D.
Guest

Jonnie Bowden does a pretty good job of illustrating these issues by using sumo wrestlers as an example:
http://alternative-doctor.com/obesity/how-a-sumo-wrestler-can-teach-you-to-be-thin/

Joy
Guest
Joy

@jason and @megan and team, love your books and blog and everything you do! Since (as I understand it), you advise that a fast consists solely of not taking anything to raise insulin and therefore pure fat is OK, do chia seeds in coffee count as part of a fast? I’ve read that chia seeds actually lower insulin. Do you agree with this and if yes, should we all be taking chia seeds to actually help with fat loss? Any thoughts from other IDM community members very welcome. Thank you all!

clbrto
Guest
clbrto

I’ve lost over 100 pounds using IF and a LCHF diet, but also do best when participating in a weight loss group (I’m low-tech ability and want to meet in person, no offense to the IDM program offered). Weight Watchers, TOPS, and the weight loss program offered at my local YMCA all use the CICO model. They drone on & on about consuming sugar, alcohol, and other diet-busting substances “in moderation”. My YMCA class handed out small candy bars to a group of morbidly obese people to teach “mindful eating” of candy. Constant eating to stave off “starvation” is encouraged.… Read more »

Gilli
Guest
Gilli

Having been on every diet invented since the 1970’s and getting fatter by the decade – finally at almost 60 I have experienced true weight loss and controlled my eating! For the past two years I have followed Dr Fung and chosen IF and followed a Mediterranean diet.. I lost over 40lb in 12 weeks and am still skinny and no longer T2 – my GP is amazed!!
If you don’t believe this way of eating works – try it!!

CSue
Guest
CSue

So if you eat low carb and IF, then reducing calories DOES allow you to lose weight, because there’s not too much insulin, so your body will burn fat instead of reducing BMR. But what I’ve never heard addressed is where that level is. Reducing calories works for me sometimes, other times it doesn’t at all, sometimes it half works. This seems to be related to how long I’ve been doing it, and low my body fat is at the time (works the least with lower body fat). My fasting insulin measures between 5 and 6. Is the problem that… Read more »

Richard
Guest
Richard

CSue: I think you start out posing reasonable question, if the question is whether everyone reacts the same way to these dietary changes, and clearly the answer is yes. But it is not unreasonable to propose that some people are more sensitive than others to various dietary changes. That is, everyone is going to have an insulin “reduction” if they fast for one day, or two days, or three…etc. And I am proposing an actual real “water only” fast, not some cheating, excuse-based plan involving heavy cream in coffee, etc. But is everyone going to hit the same numbers? Probably… Read more »

Mamasan
Guest
Mamasan

This Nigerian prince use argument is straight from Freakonomics

dolph
Guest
dolph

You know, today I had a light bulb moment and realized how right Dr. Fung is. Still doesn’t change my viewpoint that nothing will really change regarding obesity in the world. I would like more posts on taste. I think this is a neglected area since the food industry specifically manufactures food to stimulate our taste buds and lead to addiction. I’ve personally found a world of difference if I eat just a few salty crackers or a piece of chocolate, or water fast. When I drink water, I feel hydrated but not satisfied. When I eat, I feel satisfied.… Read more »

JohnM
Guest
JohnM

Many resonating thoughts in there, dolph. It wasn’t that long ago for anyone of us, that we too would’ve had something far more important to do that would have easily superseded addressing health and weight loss. It happens when we’re ready and not before. Logic will never convince anyone of anything until our feelings agree that something must be done. Fasting definitely reveals an unexpected satisfaction that occurs with meal preparation, taste, chewing and swallowing. Young for my age and vibrant is what I’m going for. Exercise is the perfect physiological example of use it or lose it. By not… Read more »

Hap
Guest
Hap

I have to agree. Fasting or not, need to create the conditions that tell your system it is not ok to adjust to lower energy substrate with what ever mechanisms to lower bmr. CR weakens people. Cycling with fasting is one way, and variably effective. Exercise is complex. Building muscle mass is an important and not exactly exercise. Muscle lost is signalling disaster as it is powerful endocrine and paracrine organ. The paradox is that building muscle requires commitment to resistance training AND establishing an adequate intake of protein. Dr fung would say that protein increases insulin but recent research… Read more »

JJ Walters
Guest
JJ Walters

More nonsense from Fung. Even in the study he references, the Minnesota Starvation, participants were all down to single % body fat by the end of the study (16 weeks). That proves that despite BMR adaptations, on a consistent diet, weight loss will result. Go read about the Twinkie Diet. But I’m sure they regained the weight after, and then some. Their metabolism was damaged. You say. Just more nonsense. As someone already stated here, the reason why these intermittent fasters lose weight is because they are fasting 1-2 days a week and that represents a 25% reduction in your… Read more »

Stephen
Guest
Stephen

The Minnesota Starvation study had nothing to do with fasting and everything to do with caloric restriction. The participants were fed 3,200 calories daily during the control phase of 12 weeks, then fed half that (1560) daily for 24 weeks during the semi-starvation period. Where do you see any reference to fasting in that study? The study did not directly measure BMR, so it is impossible to say if the participants ever hit a level where 1560 calories per day would meet their needs. I suspect not, as the participants were all healthy white males 33 years old and younger.… Read more »

Mike Santos
Guest
Mike Santos

There is no such entity or entities whatsoever as calories. They are entirely fictitious and so are ergs, inverse fermions etc., no difference. Energy is not….anything….. It is abstract mathematical FICTION we humans invented as an accounting trick.

kr k aravindan
Guest
kr k aravindan

why there is no obesity code podcast since one month /?

Sara
Guest
Sara

Dr. Fung- I just picked up your book yesterday but to me you are really missing the boat, glossing over the exact mechanism as to why Intermittent fasting can avoid your body reducing its calories like every other diet. This is the subject of lots of confusion on many boards. With people not knowing what to do and why. I was lost for a while but I already had a theory that seemed to be the natural missing link. My theory is that Intermittent fasting can allow you to reduce your calories and NOT have any reduction on your calories… Read more »