The Calorie Calamity

Adam Plotkin
26 min readJul 13, 2020

Before I dive into today’s topics, I want to give you a fair warning that in order for me to simplistically elucidate on several topics, I will need to use a bit of physics, math, and biochemistry (Thanks for the Liberal Arts education Cornell!)

My goal for this article is quite straightforward:

I want to first prove to you that the concept of a “calorie” is far more complex than we make it out to be, and in doing so, I hope to demonstrate that the art of calorie counting is highly flawed. Once that is established, I plan on demonstrating quite a radical theory: I propose that a calorie is in fact not just a calorie. This isn’t a new idea per se, but it is radical in the sense that this notion is often forgot by the calorie counting world and overlooked by many individuals on their health journeys.

So, I guess a great place to start is with everyone’s favorite topic in nutrition: the calorie. Despite what you may have heard, these are not little monsters that sew your pants a little bit tighter every night. If any of you have taken a chemistry course before, you may be familiar with the basic science definition of a calorie:

“one calorie is the amount of heat required to raise the temperature of a litre of water by one degree Celsius.” So using the basic science definition of a calorie, we see that a calorie is simply a unit of heat. Sweet, that’s it for today’s article, nothing else to discuss!

If only it was that easy. I mean that definition is meaningless to about 95% of the population, so what the hell are we supposed to do with this? Well this is where things start to get a bit hairy. Our body is not simply heating a litre of water by one degree Celsius…it is sustaining life…a highly complex process, to put it lightly. This boils down to energy efficiency. The calories required to raise one litre of water by 1 degree Celsius is stagnant, but just think about the discrepancy in energy required for a trained marathon runner to complete 1 mile vs the same 1 mile being completed by an obese individual…yeah I would call that highly dynamic. So this necessitates a different type of definition for a calorie.

Have you ever wondered how scientists figured out how many calories are in your favorite foods (that we see listed on a nutrition label)? They use something called a bomb calorimeter. Think of this bad boy as a suped-up Easy Bake-Oven. This small air-tight oven is placed in a large bucket of water, a certain type of food is placed inside the oven, the chamber is closed, and the food item is electrocuted. The heat produced via this burning food item then warms the water surrounding the oven. And here is where the basic science definition comes into play: if the water temperature raises by say 50 degrees Celsius…well then that food contains 50 calories. This seems a bit round- about way to do things, but time and time again we see these results are fairly reproducible, thus giving food scientists the caloric information they need to fill out a nutrition label.

Pretty neat right? The only problem is that I don’t know about you, but I am not an Easy-Bake Oven! The human body is infinitesimally more complex than a bomb calorimeter. In simple terms (I will explain in a bit more detail later), let’s say scientists find that a piece of bread placed in the bomb calorimeter raises the water temp by anywhere from 75–90 degrees Celsius (then after several re-tests, an average of 82 kilocalories is calculated, so the bread has a caloric value of 82 kilocalories). Our body does not simply heat up the bread when we ingest it, and automatically use the 82 calories it produces (heck that piece of bread could supply our body with a huge range of calories). Think about how much these discrepancies add up over time. And yet, we meticulously track the calories listed on the back of a package of food, thinking that whatever is in listed on the label is gospel and that absolutely every last calorie will be absorbed and expended.

As en axample, say you calculated your baseline caloric intake is about 2,000 kilocalories. Based on nutrition labels, you decide to eat 1,500 kilocalories a day (a 500 kilocalorie deficit). However, in actuality, due to the nutritional label error, and your individual variability, you are unknowingly consuming 2,100 kilocalories a day, which would actually result in weight gain over time.

My point being: There are many variables we must consider within the human body itself. For instance, the amount of lean mass to fat mass an individual has, their current stress levels, how much you have moved your body prior to consumption, and sleep levels to name a few.

On top of this, food companies are sloppy in their measurements. As we discussed in previous articles, a lot of the food we see in our grocery stores are made of multiple ingredients. Well, food scientists tend to measure each ingredient individually, and then simply add the caloric values together to get the final value that we see placed on a nutrition label (1). Therefore, this estimation of total calories in an ultra-processed (or even minimally processed) food creates a problem in the form of total caloric intake error. I love the way Dr. Lagakos explains this in his book, “The Poor Misunderstood Calorie.” People do not simply sit down and eat foods in individual components, rather we eat total foods. What do I mean? Most people will not sit down at a dinner table and eat 23g of protein, 52g of carbs, and 17g of fat, instead they eat a large slice of pizza (i.e. total food, not the components of food in the form of individual macro nutrients). With such a simplistic view, one might think, “Ok, well if my slice of pizza is made up of 23g of protein+ 52g of carbs + 17g of fat, then that equals a total weight of 92g or roughly 3.3 oz. The only problem is that your slice of pizza most likely weighs more than 92g due to water weight and air content…yet another wrench in our thinking (1).

So now that we have somewhat hacked into the flawed nature of using the nutrition label to count calories based on food science (say it with me…”I am not an Easy-Bake Oven), there is one more common definition; the nutritional science definition.

The nutritional science definition looks to examine caloric expenditure IN REAL PEOPLE! To do so, they use a piece of equipment called a direct calorimeter (It is similar to a bomb calorimeter, but on steroids). Instead of an oven, the direct calorimeter is the size of a typical bedroom, so a person can fit inside comfortably. Scientists are thereby able to directly measure the heat produced by this individual at any given time, while this individual is doing any given activity (sleeping, sitting, running on a treadmill, etc…). This is an exact calculation and through many many many studies, scientists have developed caloric expenditure equations (which I am sure that many of you are unknowingly familiar with).

Maybe you have used an app like MyFitness Pal before. They ask you to put in your age, weight, gender, race, activity level, etc…and boom just like that, the app spits out a caloric value that is your baseline caloric expenditure (all based off of equations generated by these direct calorimeters). Seems pretty great huh! I mean its an exact calculation, what could go wrong? Well, the direct calorimeter is only accurate for that specific activity at that specific time. For instance, if I were to sit in this direct calorimeter and just stare at a wall for 24 hrs and the machine tells me that I burn 2,000 kilocalories over a 24 hr period, that’s great and all, but how applicable is that to everyday life? I mean obviously I am not going to sit and stare at a wall for 24 hours in real life, but let’s say I repeat the same exact experiment the following day and this time the direct calormeter calculates that I only expended 1,800 kilocalories. What gives? Well, even though externally it appears that the situation is the same, our metabolism is so variable on a day to day basis that something internally must have changed, causing a decrease in energy expenditure over that 24 hr period. Things such as when we last ate, sleep levels, and stress levels have a great deal of sway in our internal milieu.

There is one more way we can determine caloric expenditure and that is through indirect calorimeter, but it is beyond the scope of this article (there is a lot of biochemistry involved). In short, this method is less accurate than direct calorimeter and measures something called your respiratory quotient (RQ). This method analyzes our inhalations and exhalations to determine the ratio of carbon dioxide exhaled to oxygen inhaled. This gives us a numerical value that tells us whether we are burning carbohydrates as fuel (typically a RQ of about 1) or fats as fuels (typically a RQ of about 0.7).

So, as you can see, the variability of food science and the human body create quite a bit of confusion when it comes to calorie counting.

So riddle me this: Why they hell are we so fixated on this Calories in vs Calories out model (CICO). I’m sure most of you know what I am talking about in some form or another. This model has a basis around the fact that if caloric intake is equal to caloric expenditure, then our body weight will remain stable (no accumulation of fat mass; this is referred to as caloric maintenance). Therefore, if caloric intake is less than caloric expenditure, we will lose weight (this is called a caloric deficit), and if caloric intake is greater than caloric expenditure, we will gain weight (caloric surplus). So how do you practically use this model? You count your calories…maybe by weighing your foods and adding values found on nutrition labels (a little more on this shortly). What a neat little model, right? Yeah, not so much.

I just demonstrated above that nutrition labels and the minutiae of the human body make our usual mathematical weight loss models obsolete. So how do we know if we are eating at caloric maintenance (calories in = calories out). Unfortunately, we have to use our body weight fluctuations over time (as a wrestler for 8 years it pains me to say this). The only way to truly know if you are eating in a maintenance, deficit, or surplus is to compare body weight over time.

So maybe I enter my data into MyFitnessPal and it uses one of those horribly inaccurate mathematical formulas and tells me that if I consume 2,000 kilocaloires a day, my body weight will remain stable (caloric maintenance; calories in = calories out). So maybe I decide to eat 1,800 kilocalories a day to be in a 200 kilocalorie daily deficit. So if I am truly in a caloric deficit, I would lose weight (Based on the 1st Law of Thermodynamics…more on this later). However, as demonstrated above, although I may be accurately adding up all the caloric values on my nutrition labels and weighing out all my foods to the nearest gram, I may not actually be in a caloric deficit (due to all the variability I covered above…and a lot more I didn’t cover). So, maybe I think I am in a 200 kilocaloire deficit, but when I check my weight on the scale in 2 weeks, I actually increased in body weight. Thus, I was not actually in a caloric deficit, but rather a surplus, and either the nutrition labels were inaccurate, the caloric prediction equation was inaccurate, or my metabolism down regulated its energy expenditure to match energy intake (or a combo of all three).

So to put this into practical sense, you need to weigh yourself on the same scale to keep consistent. You can use MyFitnessPal or a similar app to determine a rough estimate of your maintenance calories. Weigh yourself on day 1, and eat the recommended amount of calories based on the mathematical equation you used. Do not weigh yourself everyday (too many fluctuations due to volume of food, water retention, etc…). Instead, wait approximately 2 weeks and re-weigh yourself in the same conditions. If your weight decreased, then you were in a caloric deficit, if it is roughly the same, you were in maintenance, and if it increased, you were in a surplus. Regardless of what nutrition labels say or what MyFitness Pal says, if you weighed 150 lbs on day 1 and 150lbs on day 14, then energy balance was in fact neutral over the course of those 2 weeks (the amount of kilocalories you ate equaled your energy expenditure) You can continue this method until you get a decent idea of what your caloric maintenance is at that time.

Now this is beyond the scope of this article, but I do not really like using the scale to determine value (although if you want to know your caloric maintenance level, body weight is the only way to accurately do so). Instead, I focus on athletic performance, daily mood/energy levels, sleep quality, and body composition/how I look in the mirror, rather than a numerical value.

To hop up on my soap box, I believe that our society places far too much value on that damn number that pops up on the scale, when in actuality we should place our focus more on quality of life and daily performance. So many of us prioritize losing 15 lbs to get down to our ideal body weight, and get frustrated when we only lose 5 lbs, but fail to see that our body is moving better, we feel happier, are sleeping better, have more energy, and have moved further away from metabolic syndrome!

Anyhow, not only are there many flaws with calorie counting that I stated above, but, this model is just way too simplistic to apply to such a complex beast like the human body. This CICO model assumes that all an individual has to do is control two things: 1) the amount of calories that go into their mouth, and 2) the amount of physical activity they do everyday, and BOOM you can manipulate your weight at will. Of course, you know what I am going to say next. It is never that easy. I mean without even citing any hard evidence here, I am sure we all have a had a run-in with calorie-counting.

I’m going to set up a scenario to you that probably will sound quite familiar.

My friend Wylie knows absolutely nothing about nutrition (or much else for that matter), so he downloads this app which tells him that he needs to eat 3,000 kilocalories a day to maintain his current weight. Wylie just read an article published in the Journal of American Medical Association (JAMA) that prescribes, “If a patient reduces caloric ingestion by 500 calories per day for 7 days, he would lose about 1lb of body weight a week” (2). Now I really hope you can understand what is wrong with this prescription. If Wylie weighs 100 kg (220 lbs) and follows these guidelines, he would “disappear” in about 4 years (do the math, I dare you). And yes this was a real prescription made by a real medical doctor that was published in a real journal!

Well, Wylie doesn’t see the flawed thinking in this prescription, and decides that he wants to lose roughly a pound a week, so he creates a 500 kilocalorie deficit (He settles on eating 2,500 kilocalories per day). This is tough, but after two weeks he is down almost 3 pounds! He keeps this up for two more weeks, but all of a sudden his weight loss stalls. Then, despite his crappy mood, his cold body, and ravenous hunger, he dips his caloric intake 200 kilocalories lower (now he is only eating 2,300 kilocalories a day). And guess what…maybe he loses two more pounds over the course of 2 weeks, but then his weight loss stops again. Depressed, tired, hungry, and frantic, he decides to only bump his calories back up by say 200 (so now he is eating 2,500 kilocalories a day), thinking, “I can’t handle eating such little amounts of food, so I’ll go back to that original 2,500 kilocalorie a day diet, because it worked so well for me before, and maybe the extra calories will keep me from feeling so shitty.” Wylie goes about his business feeling a bit better with these extra 200 kcals and then checks his weight at the end of the week. To his astonishment, he gained 2 lbs. Wylie says, “What the heck, I lost a ton of weight eating only 2,500 kcals a day, what gives?” Well what did Wylie do wrong? He fell for the oldest trick in the book.

What did I just explain above: When it comes to counting calories, the scale never lies. Wylie started out on this crusade with a daily caloric expenditure of 3,000 kcals a day. So to see weight loss, he only ate 2,500 kcals, but after a few weeks, the scale stopped budging. Well that means that his caloric intake was equivalent to his caloric expenditure (so Wylie is now only burning 2,500 kcals a day rather than 3000). Then by dropping his caloric intake even more (now at 2,300), he successfully made his caloric intake 200 kcals less than his current expenditure of 2,500, so he lost weight again. Then he stalled out for the second time (so his expenditure must now be at 2,300 kcals). But then he made the fatal flaw that I am sure we all have made: By increasing his calories back to 2,500 kcals, Wylie actually put himself in a caloric surplus of about 200 kcals, leading to weight gain!!!

You see, our metabolism is smart…I’m talking 36 on the ACT and 4.0 GPA at Oxford, smart. It will do everything in its power to make sure you don’t wither away into nothing. So when you cut your calories, whether you know it consciously or not, your metabolism adjusts your caloric expenditure to match your caloric intake (this is a slow-ish process and usually it occurs sub-consciously). And most people try to compensate by exercising longer or harder, but what people don’t understand is that you actually burn a lot less calories working out than you think you do (This is worthy of its own article…long story short, your Garmin watch is horribly inaccurate). More likely than not, you will just unknowingly fidget less, move around the house less, and just overall be a bit more sedentary throughout the day, which overtime will bring your caloric expenditure equal to your caloric intake.

So where is this CICO model going wrong? I’m not arguing that this way of calorie counting doesn’t work…I mean it clearly does work in an acute fashion. But here is the $1,000,000 question that we all should ask ourselves: If this model was sustainable and worked “forever” why wouldn’t everyone be doing this? Or better yet, why do we hear stories of people like Wylie who have initial success and then rebound?

Well, I may not have a $1,000,000 answer, but here is my stance:

The CICO model makes one fatal flaw (actually it makes quite a few…but those are stories for another time):

This model assumes that a calorie is simply a calorie. According to the CICO model, 1 calorie of protein = 1 calorie of carbohydrate = 1 calorie of fat. Yet, this model fails to consider what these macro nutrients due to our body once ingested.

Confused? Good! Let me distill this down:

The people who tout CICO as the end-all-be-all always hang their hat on this damn 1st Law of Thermodynamics (Physics…I know, I just puked a little bit as well).

The first Law of Thermodynamics is a conservation law stating that the form of energy may change, but the total energy is always conserved in a closed system.

Of course, one cannot simply outsmart the laws of physics (unless you are Wesley Gibson from the movie “Wanted”), so this law is always true…but I believe it is irrelevant based on the complex nature of human physiology.

My reasoning is quite simple, the CICO model assumes that the calories going into the system and the calories being used by the system are the same. This is flawed thinking. To bring in a bit more physics, think of dietary protein, carbs, and fats as potential energy. The energy is stored in their carbon-carbon bonds, but we have no way to use that energy until we break these macro nutrients down into usable kinetic energy (If you are familiar with ATP, this is one example of endogenous kinetic energy). See, the total energy remains conserved (1st Law of Thermodynamics), but the forms of energy are different and exert different impacts on our metabolism, which suggests that a calorie is in fact not just a calorie (and this concept actually relates to the 2nd Law of Thermodynamics…but I think we can save that headache for another time).

Let’s say we have two individuals, both with a baseline energy of 2,000 kcals per day and both individuals are weight stable (caloric maintenance). One decides to use the traditional low-fat high-carb approach and the other tries the unconventional low-carb high-fat approach. Both eat an isocaloric diet (same amount of calories) and are in an equivalent caloric deficits (let’s say both individuals are eating 1,500 kcals a day of their respective diets).

So, if all else is considered equal, and if a calorie really is just a calorie, then theoretically we should see equal weight loss between the two individuals regardless of the composition of their diet, because calories were matched.

But, I am arguing that in fact, a calorie is not just a calorie, and that we would potentially see that the individual on the low-carb diet will lose more weight due to some postulated metabolic advantages of this dietary approach.

What do I mean by metabolic advantage and why can we not simply lump all calories into one neat pile?

  1. Our body requires more energy to break down and assimilate protein when compared to the break down of carbs and fats (this is called the thermic effect of food). To put a numerical value to this term, research has demonstrated that about 25–30% of calories from dietary protein will be burned after consumption, in comparison to 2–3% for fats and 6–8% for carbohydrates (3,4). So in practice, if I were to eat 100 calories of protein, my body would burn 25 of the calories just through digestion and assimilation, whereas, if I were to eat 100 calories of fat or 100 calories of carbs, my body would only burn about 2.5 and 7 calories, respectively.
  2. Let’s say an individual is in caloric maintenance (think of this as a zero point; for example if they take in 1 calorie they would be in a +1 calorie surplus, and if they were to burn 1 calorie, they would be in a -1 calorie deficit). If this individual were to eat 100 kilocalories of pure protein compared to 100 kilocalories of pure carbohydrates, consumption of the protein would result in a lesser caloric surplus.
  3. Then let’s think of the flip side, what would happen if the individual decided to cut out 100 calories of carbs or 100 calories of protein from their daily caloric intake. Well you would actually be in a greater caloric deficit if you cut 100 calories of carbs, because the energy deficit you would gain from cutting 100 calories of protein would be negated by the energy saved from not having to digest and assimilate the protein.

So when you think of it, 1g of protein and 1g of carbohydrate are both “worth” 4 calories, and if you were to put 1g of protein and 1g of carbohydrate into a bomb calorimeter, sure enough, that’s exactly what you would see. But, what about when you put that 1g of protein and 1g of carbohdrate into your body…they do not provide the same amount of energy to the body.

4. To continue on with out carbohydrate example, the CICO model fails to consider the difference between a high and low glycemic carbohydrate (glycemic index; GI). If a carbohydrate is considered high GI, that means it causes a big and rapid spike in blood glucose, followed by a sudden crash (more on this shortly). Whereas, lower GI carbs are digested and released in a slow and sustained manner. I am sure that many of us are familiar with the notion that if we are going to indulge in consuming carbs, it is probably in our best health interest that we eat low GI foods (think whole-grain pasta) rather than high GI foods (like a Brown Sugar PopTart…grody). Doing some calculations using MyFitnessPal, I found that about 1.2 cups of whole-wheat spaghetti is isocaloric to one serving of Brown Sugar Frosted Poptarts. So using the CICO model, these two food items are equivalent. Now you tell me…when we ingest these these two isocaloric meals…are they really equivalent?

Hormones pay a significant role in our metabolism, and should absolutely be considered in our calorie counting model. In fact, there is one imperative hormone that this model overlooks, and I am sure you are all familiar with it: Insulin. In brief, if we eat a carbohydrate (and actually dietary protein causes some insulin to release as well) the carbohydrates are broken down into simple sugars and released into the blood stream. You may be familiar with the term blood sugar. Well it turns out that we only have one hormone that lowers blood sugar, and it’s our friend, insulin. So insulin’s role is to take that blood sugar and either store it as glycogen or store it as fat (denovo lipogenesis), and importantly, insulin also inhibits the burning of fat (lipolysis). So if insulin is high, you are storing glucose either as glycogen or as fat, and thereby unable to burn body fat stores. Thus, higher GI carbs (like our PopTart) cause a rapid and high release of insulin, whereas lower GI carbs (like our Whole-Wheat spaghetti) release a slower and lower amount of insulin. Nevertheless, the CICO model would treat these carbohydrates as equivalent, because they are matched on a caloric basis.

And once again, when just looking at things from a highly-simplistic biochemical perspective: a well-formulated low carb diet will obviously limit insulin, thereby limiting fat storage via this mechanism, and more importantly, allow for almost continual burning of stored body fat. Whereas, an individual on a reduced-calorie low fat diet may be eating fewer calories than an individual on a low-carb diet, they would be raising insulin levels much higher and much more frequently than a low-carb dieter, thereby potentially leading to increased fat storage and inhibition of fat burning.

5. Without getting too deep into the weeds on this one (I plan to make point #5 its own article), when on a carbohydrate restricted diet or in the fasted-state, our metabolism uses non-carbohydrate sources (like protein or glycerol from fat) to make glucose to fuel our body (especially our brain). This is a process called gluconeogensis and occurs primarily in the liver. Gluconeogenesis is a metabolically expensive process to maintain. Ultimately, the liver needs some form of energy input to produce the necessary glucose, and it gets this energy from the breakdown (oxidation) of fat. So the metabolic advantage of being on a low-carb diet is that when glucose is coming from gluconeogenesis, the body is in a negative fat balance (a fat deficit). So, on an isocaloric low-fat and low-carb diet, due to gluconeogenesis, energy expenditure is increased on the low-carb diet.

Although I have explained the biochemistry behind it, you do not need to take my word for it. In a study conducted by Veldhorst et al., (2009), the daily caloric expenditure of healthy young men on a diet formulated to maximize gluconegonesis (there were multiple factors in this diet, but importantly carb intake was completely restricted) was compared to the daily caloric expenditure of healthy young men on a standardized diet. The carb-restricted group had an increase in daily caloric expenditure of 5% (5). And that may seem pretty wimpy, but if we went back to our example of Wylie, eating 3,000 calories a day to start, 5% of 3,000=150 calories per day. If Wylie were in a daily 150 calorie surplus, he would gain almost 16 pounds over the course of that year (based on the 3,500 calorie rule stated above). Lastly this study demonstrated that the energy required to produce glucose via gluconeogenesis was 1/3 that of the total energy of the final product (which is glucose). Think of this like spending $0.33 to earn a $1, as opposed to picking $1 up off the ground (1).

The bottom line: gluconeogenesis is a process that is utilized in a carbohydrate or food restricted state, and is expensive to maintain and highly wasteful, thereby potentially conferring a metabolic advantage over time

6. It is pretty well established that there is a hierarchy in terms of satiety (feelings of fullness) among the three macro nutrients with protein being the most satiating and fat being the least (6,7). Therefore, although 1g of protein and 1g of carbohydrate have the same caloric value, on a satiety basis they are not equal. Dietary fats also take a longer amount of time to fully digest when compared to dietary protein and carbohydrates, thereby causing delayed, but prolonged bouts of fullness (8, 9, 10). Thus, it is quite possible that a high protein, high fat meal will create feelings of fullness more rapidly while also lengthening this fullness when matched with an isocaloric high carbohydrate meal.

Now to put this all into persepctive, let me show you a brief example:

Consider our same Brown Sugar Frosted PopTart from before, compared to an isocaloric meal of fresh-wild caught salmon. Sure these meals are matched on a calorie for calorie basis, but how they are metabolized in the body is quite different.

The salmon on one hand is composed of mainly protein and fats. When that protein is degraded into amino acids, those amino acids are going to be used to synthesize new skeletal muscle, enzymes and structural proteins (some of the amino acids may be burned, but that is a story for another time). Essentially, these amino acids will be used to build the body up (anabolism). Salmon is also rich in these very long chain unsaturated fatty acids like EPA and DHA (these are omega-3 fatty acids). These types of fats stimulate certain nuclear transcription factors that are involved in fat oxidation, so essentially EPA and DHA enhance fat burning, which puts the body in a fat deficit (1). In fact, a study of Omega-3 supplementation in elderly community-dwelling females over the course of 12 weeks demonstrated significant increases in resting metabolic rate (+14%), energy expenditure during exercise (+10%), the rate of fat oxidation during rest (+19%), the rate of fat oxidation during exercise (+10%), lean mass (+4%), and functional capacity (+7%), whereas the placebo group (supplemented with olive oil) saw no change over the 12 weeks (11).

On the other hand, digestion of the Poptart will cause the release of glucose into the bloodstream. Increased blood sugar signals the release of insulin, insulin removes glucose from the blood stream, causing a period of hypoglycemia (low blood sugar). Periods of hypoglycemia are associated with increased feelings of hunger (11). So with this hunger, what do you do? Well you eat more food (usually containing carbohydrates) which starts the cycle over again. We know that insulin also stimulates the growth of fat cells, and what do you need to fuel said growth? You guessed it…more food, thereby potentially increasing food intake.

So even though the Salmon and Poptart are matched for calories, once they are metabolized, they produce polar opposite effects.

So my point in writing this long article was to hopefully demonstrate to you that the art of calorie counting is not as straightforward as many of you believe.

When we boil things down, those on the CICO approach tend to gravitate towards the reduced-calorie, low-fat diet, because fat of course has 9 calories per gram, so let’s just cut those energy dense fat calories down, right? Solid reasoning of course, but does it work in practice?

In one of the largest empirical dietary intervention studies to date, the low-fat diet was put to the test. This study included over 50,000 women and lasted 7 years (Women’s Health Initiative Dietary Modification Trial). The premise was simple: 60% of the women were told to just continue life as per usual, whereas the other 40% were placed on a low-fat diet/lifestyle for 7 years. The low fat group reduced their fat intake by about 23% and increased their physical activity by about 14% compared to their pre-study baseline. Yet, after 7 years, there was NO SIGNIFICANT DIFFERENCE BETWEEN THE TWO GROUPS. Therefore, the women on the low-fat diet would have fared exactly the same if they had never been a part of the intervention in the first place. Additionally, when doing subgroup analyses, the researchers determined that women in their 50’s gained weight and women (of all ages) who were considered“lean/healthy body weight” before the intervention, gained weight as well. So what do we take from this enormous and lengthy study: 1) The low-fat diet is not an effective method to lose weight, and 2) if one is at a healthy body weight or middle-aged, a low-fat diet may actually lead to weight gain (13). The researchers came to the conclusion that since energy balance is always maintained (1st Law of Thermodynamics), the women who reduced fat intake most likely over-compensated their carbohydrate intake, resulting in weight gain.

On the flip-side, the basic premise of the low-carb diet is that this increase in energy density (more fat) will lead to less bouts of hunger and less food consumption over time (and potentially that controlling insulin will favor fat loss…but more studies are needed on this).

In a 2004 clinical trial, subjects were split into two groups: 1) a low-carb group with no calorie restriction, and 2) a low-fat, reduced calorie group

At the end of 1 year, the low carb group lost more weight than the low fat group, and although the low-carb group had no restrictions on their caloric intake, they spontaneously reduced their caloric consumption. Since the low-carb group had no restriction on calories, they would simply eat whenever hungry, and this was of course less often than the low-fat group, thereby implying that the low-carb group was simply less hungry than the low-fat group. Thus, although the energy density of the low-carb diet is greater than the energy density of the low-fat diet, the low-carb group simply ate less of the calorically dense food. Whereas, the reduced caloric density of the low-fat diet allowed the other group to eat more food in terms of volume, but clearly these low-fat foods were not as satiating, thereby resulting in the consumption of more food and more calories!!! (14).

So in the end, calories are irrefutable. There is no way around these suckers. You consume less calories than you take in, and you lose weight. You take in more calories than you expend, and you gain weight. The only problem is that a calorie can not simply be thought of as just a calorie. Carbs, fats, and proteins exert distinct perturbations in our metabolism that either shift us favorably towards burning fat and building new tissue or shift us towards storing fat. So once again I urge you to pay more attention to the quality of the food that is going down your gullet, rather than the caloric composition of said food.

Yet, if you were to ask most “fitness experts” they would of course tell you to count your calories and that of course you can eat 10 Poptarts a day, as long as your caloric intake is less than your caloric expenditure. And to that oh-to-familiar notion I will say that it seems the lunatics are running the freaking asylum.

I hope after this long-winded article, you can see the flaw in this way of thinking.

  1. Lagakos, William. The poor, misunderstood calorie (p. 64). Unknown. Kindle Edition.

2. Guth, Eve. “Counting Calories as an Approach to Achieve Weight Control.” Jama, vol. 319, no. 3, 2018, p. 225., doi:10.1001/jama.2017.21355.

3. Jequier E. Pathways to obesity. Int J Obes Relat Metab Disord. 2002;26 Suppl 2:S12–7. doi: 10.1038/sj.ijo.0802123

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Adam Plotkin

Post-Baccalaureate research assistant in the Molecular and Clinical Nutrition Lab at the National Institutes of Health