CLIFF NOTES:
The following was written by Graham Ballachey. Graham and I met through a web debate that took place on a site called “Mark’s Daily Apple.” So here’s Graham:
Calories in vs. calories out is still the bottom line for weight loss. However, if all that matters is total calories, then why bother avoiding most sugar and carbs, as long as we don’t consume too much? The answer lies in long-term hunger control, and the havoc that processed sugars and carbs have on our appetite regulation systems. For most people, processed foods result in chronic overeating while avoiding them results in suffering-free caloric restriction over long periods of time. Eat junk, and you can’t trust your hunger. Eat real food, and let hunger be your guide to a lean body.

I’m here to write about the “Calories in vs. Calories out” model of body fat level. Sam and I have noticed that there is a lot of confusion and misinformation within the primal/paleo community, and the “normal” community at large on this topic. Far too frequently does the phrase “eat all the bacon you want, but no toast” pop up amongst the advice offered by primal/paleo circles. If you’re not familiar with the primal/paleo philosophy, you can find information on it all over Sam’s blog, or simply type it into google and you’ll get more info than you can handle. It wasn’t that long ago that I was someone who promoted this notion, and to a point I still am. I will elaborate on this further below as for now I want to focus on the topic at hand: the calories in vs. calories out model. I have to say, after 10+ years of reading about health and fitness fanatically, working out intensely in many different ways, and trying many different combinations of macronutrient ratios, eating schedules, and supplement regimens in the name of learning the ideal lifestyle to promote a lean, healthy, muscular body, that calories in vs. calories out is completely, and simply, true. Calories in vs. calories out determines body fat levels, straight up. It’s the first law of thermodynamics playing itself out inside your body. You can’t beat it (trust me, I’ve tried). The twinkie guy proved it. No intense exercise and eating mostly sugary junk food resulted in significant fat loss over a period of several weeks (and pissed me off in the process, haha) since he restricted calories to a level below his metabolic rate. Jerk! Or is he?
Overconsumption and Underconsumption
You can blame it on junk food all you want, but in reality every single ounce of fat on your body (some of which is essential, the rest is not…) is the result of overconsumption at some point. Not overconsumption of any particular food, but overconsumption of pure food energy (calories). Similarly, if you’ve ever lost weight (fat) in your life, it wasn’t due to an exchange of one type of calorie source for another, it was due to a caloric deficit racked up over a period of time: underconsumption. Unless your body somehow has the power to “absorb” food energy from some other source (like the breatharians claim, haha), or your body somehow dumps energy without using it (this can happen to a degree, but its very minimal, see below), then the energy balance within your body is 100% represented by what you have swallowed and burned off (or, I suppose injected, but who actually does that?).
For the purposes of this article, I’m not talking about “health” in general (quality of life, longevity, resistance to infection, digestive health, etc.), but about the very sad ~70% of adults in the North American population who carry around an excessive amount of body fat. By this I mean being anywhere considered “overweight” to “obese”. That being said, it is in my personal opinion that the above definition of health can’t be completely decoupled from obesity as they are clearly linked, but for the purposes of this article the focus will be solely on body composition, and specifically body fat levels. Also for the purposes of this article, I’m going very light on the details behind the physiology of fat gain/loss and will use minimal terminology without accompanying description. All I’m going to assume is a basic understanding of calories in general, a basic understanding behind the differences between a carbohydrate, a fat, and a protein, and an understanding of a what a processed food is as opposed to a whole (or minimally processed) food is. Also, I’m hoping you don’t have the “fat is bad” or “cholesterol is bad” myths floating around your head though I know some of you still will. You want MORE details? Read up from a variety of sources, or talk to Sam!
The Online ‘Fight’ with Primal Enthusiasts
The motivation for writing this article arose when I noticed Sam in the comments section of Marks Daily Apple (MDA) for the article “Why Can Some People Eat Anything They Want and Never Gain a Pound?” arguing with strict primal/paleo adherents that calories are the bottom line while some of them were arguing that cutting out a specific macronutrient, carbohydrates, while increasing the relative amount of another macronutrient, fat, was the key to body fat reduction. The majority of them argued exclusively about refined/processed carbohydrates (in essence, donuts vs. apples as carb sources), but in the end their point was the same: It is the source of the calories that matters, not the total amount. Sam was arguing that total calories do indeed matter! The debate got fairly intense. I wrote to Sam with the advice to not even bother bringing that fact of science up in those particular (paleo/primal) forums as few people within those forums are willing to believe it, and it’s pointless to argue with that crowd (sometimes, and really only on this particular subject). There were references to the “metabolic advantage” that exists within a metabolic state known as ketosis, which occurs when your body is severely deprived of carbohydrates. The idea is that with this advantage you could consume a seemingly endless amount of calories while still losing fat. Like I mentioned above, I used to believe and even promote this mentality, but as a physicist/engineer (had to put that in somewhere) I also knew that the laws of thermodynamics could not be broken. Now, it does turn out that during ketosis your body will “ditch” some energy without burning it, but its minutiae compared to simply reducing total calorie consumption, and if you manage to get enough calories during ketosis (to match your metabolic rate including the tiny “ditch”), the net result over the long term is the same: no fat loss! This is where “eat as much bacon as you want, but no toast” starts to break down. Bacon has lots of calories!
So then, why does it work? Why do we hear these stories about people “going primal” (or, almost equivalently, following something akin to the Atkins diet – low carbohydrate) and quickly losing a significant amount of body fat without counting calories, without feeling particularly deprived, and even (after an initial adaptation period) becoming energized from it? If you believe what I’ve said so far in this article, that in order to lose body fat there must exist a caloric deficit within the body over a long period of time, then why weren’t these people as hungry as other dieters who created the same caloric deficit, but from a diet that still included a relatively large amount of carbohydrates (most of them quite processed – grains, sugars, etc.)??? Well, here is where the source of your calories starts to make a big difference in the factors I’ve concluded are the most conducive to fat loss: SATIETY AND APPETITE CONTROL!!! Basically, which sources of calories will turn your appetite off when the appropriate amount of food has entered your body, and which won’t? What types of food will make caloric restriction easy over the long term, and which make it a real pain in the gut?
My Hunger Experiments
I’ll start my answer to those questions with a little thought experiment (which you could even try out!). On a given day, have a large bagel for breakfast (meaning your first meal of the day, doesn’t have to be first thing in the morning). A large bagel, according to caloriecount.com, contains about 360 calories derived almost entirely from processed carbohydrates (actually, kcal, but more commonly known as calories), which really isn’t that much on the grand scheme of things. Feel the satiety that occurs upon eating it, and note the time. Go about your usual business, and note the time that your body says “time to eat again!”, in the form of a hunger pang or desire to eat. For me, this is about 2-3 hours (sometimes even less), and I’m hungry again. Usually real hungry. Skip lunch? No way! We could take the bagel example to the extreme by noting that a can of coke supplies about 150 calories of pure processed sugar calories. Have 3 of them for breakfast and you’re beyond your bagel calories, but you’ll be hungry, and hungrier, even earlier! This eventually results in a pattern I can only describe as addiction. This is what happens when we eat unnatural foods. Our natural appetite regulation system gets all messed up. It’s sad.
Now, on another day’s breakfast, use those 360 calories differently. My carton of eggs tells me that an average egg (1 large egg) contains about 70 calories derived entirely from unprocessed, whole food fat and protein (essentially no carbs at all, and nothing processed). So, for 360 calories, you can have 5 eggs (woah!), plus some spinach and tomato for colour (the other ~10 calories). Now, feel the satiety that occurs from your 5 egg + spinach/tomato meal, and note the time. As before, go about your usual business and wait for that hunger signal. I guarantee you it’ll be at least 4 hours (unless you’ve done some CRAZY exercise in that time span, or you are a super tall or muscular guy). And its not the sharp, annoying hunger you experienced after the bagel, but a light, fleeting hunger that more says “stomach is now empty: you could eat, if you want to”. Skip lunch? No big deal. Sometimes you’ll full-on forget to eat lunch!
It’s All About The Appetite!
This might not happen the first time after you eat eggs for breakfast, but after an adaptation period (the length of which depends on the individual) I find this is what I hear from most low-carb adherents. There is a noticeable reduction in frequency and severity of hunger with this style of eating. Even during short-term periods of complete caloric restriction (known as intermittent fasting, usually not beyond 24 hours, at least for me!) there is no loss of physical strength or stamina, nor is there a noticeable decline in mental acuity. In fact, do this enough, and you’ll find skipping a meal energizing! For me it’s at the point where I really don’t like to eat anything for several hours before a workout, and if I have a really productive day planned its perfect for fasting (as long as I’m not super stressed or sleep deprived). Obviously, doing this everyday is counterproductive to overall health (we do need to eat to survive afterall), but on the low-carb (paleo/primal) diet, it can occasionally feel great and make you stronger while shedding off lots of body fat! And even on non-fasting days, you’ll find it difficult (though, not impossible, see below) to pack away enough food to get fat. This simply does not occur with a diet based on processed food with significantly more carbohydrates. Those diets (you know, the ones the vast majority of our society blindly follows) make restricting calories really suck. It makes you feel like shit. We see the results everywhere: fat, hungry people. Just take a look around.
Now, to get back to the article from MDA where I met Sam, you might be thinking “Well fine, but why can some people eat crap and stay thin?” It’s for the same reason that primal people don’t typically gain weight, they restrict calories! I’m not sure why some people can manage to control their appetites on high sugar diets while others can’t, but certainly physical activity comes into play, and so might genetics. Let’s be honest though; those people are the overwhelming minority, so don’t even bother trying to figure it out. There’s also the counter-example of people who are extremely active, yet still can’t lose significant amounts of fat. You can observe this directly by attending the next marathon in your city and counting the surprisingly high number of people who just finished training and competing in a marathon, but still carry around excess body fat due to their eating habits. However, if you find you are one of those people who can eat large amounts of processed carbohydrates every day without any acutely ill effects, I would still urge you to improve your nutrition, but would realize that some people (very few) can restrict calories without suffering, independently of food choices, but most can not. For most of us, unless we want to measure and count every friggin’ single calorie we consume, and go hungry after we get to our predetermined caloric limit (like the twinkie guy), going primal (low carb, higher fat, moderate protein, no processed foods) is the way to go for lifelong bodyfat control. It allows us to follow our hunger instincts without chronic overeating since our hunger instincts will be functioning properly in the absence of frequent, large amounts of processed carbohydrates. While eating primally, you will have your hungry days and your big meals, but over longer periods of time you will restrict calories without even thinking about it.
Okay, and now back to the “eat all the bacon you want, but no toast” type of ideas. Its clearly BS, but does work over long periods of time in the same way described above. Say you binge and eat a pound of bacon – like 700 calories. Gross, I know. I will admit I have done this while eating primally, and here’s what I noticed. After overeating high-fat foods while restricting carbohydrates over long periods, my appetite would disappear almost entirely for longer periods than I was accustomed to, leading to undereating over the next while until I was back to square one. So I am eating “all the bacon I want”, and it turns out I just don’t want to eat that much of it! If I were to cram back more and more and more bacon (or eggs, or avocado, or nuts, or meat, or whatever high-fat primal food I wanted), I would definitely gain fat, but I wouldn’t be following my instincts. I would be eating well beyond the point of satiety, in the complete absence of hunger. Blech!
Conclusion
So in the end, the calories in vs. calories out model of bodyfat levels is completely true. Accept it! The success that accompanies eliminating frequent large amounts of processed carbohydrates lies in making restricting calories easy and unnoticeable. You could lose fat while eating mostly breads, pancakes, and cookies, but you’ll hate it. It’s a heck of a lot easier with meat, eggs, and veggies (and some fruits and nuts, mmmmm). And now that we know that the easiest way to really increase lifespan is through caloric restriction, isn’t finding a sustainable way to do so without hating your life important? I think so.
As a final note, please realize that following your instincts while eating primally will definitely lead to a leaner, healthier body over time. If you want that super-lean, ripped, cover model look 365 days a year, there is more to it. This requires more regimented timing of training and nutrition and all sorts of “phases” like bulking and cutting. It’s completely irrelevant to most people. That being said, I love that shit! And Sam is an expert. Just check out his pics! He’s also full of great advice to get to that next level, if that’s what you are interested in doing.
Oh yeah, and once you’re adapted to low carb, the occasional cheat is really no big deal once it becomes the exception. While transitioning, I truly recommend strict adherence, or those cravings come right back. It’s the sugary slope!



