The problem with "calories"

July 9, 2015

I’m often to quick to challenge the assumption that counting calories is necessary for healthy weight loss. I state this point often on Twitter, but I suppose I’ve never fully explained my stance. I’ll do so here, trying my best to not offend or ostracize.

It all started with a tweet by yours truly:

Am I gonna have to be that guy who writes a blog post defining what a calorie actually is? Does anyone actually know without Wiki-ing it?

People have referenced “calories” day in, day out in all sorts of contexts, but I fear that not many people truly know what it is they speak of. Let’s cheat and go to Wikipedia:

  • The small calorie or gram calorie (symbol: cal) is the approximate amount of energy needed to raise the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere.
  • The large calorie, kilogram calorie, dietary calorie, nutritionist’s calorie, nutritional calorie, Calorie (capital C) or food calorie (symbol: Cal) is approximately the amount of energy needed to raise the temperature of one kilogram of water by one degree Celsius. The large calorie is thus equal to 1000 small calories or one kilocalorie (symbol: kcal)

Right off the bat, we’re faced with a dilemma of semantics: these aren’t calories we’re talking about; they’re kilocalories. Furthermore, I tend to challenge the status quo by asserting that we should not refer to calories as “something we consume,” but instead simply as the measure of energy that they are.

The original semantic debate (which raged briefly on Twitter) stemmed from a piece by Matt Gemmell, wherein a line caught my eye and irked me: “Our bodies are burning energy all the time, and we need to consume calories (in the form of food and drink) to supply that energy.”

You don’t consume calories to supply energy—energy is not the result of calories. Nay, you consume food, measured ultimately by its composition of macronutrients, which in turn provide various measures of energy (as stored in the molecular bonds within) which is measured in kilocalories (kcal). Generally, carbohydrates contain four kcal/gram, protein closer to three kcal/gram, and fats around 9 kcal/gram. In any case, calories ought not to be thought of as some baseline for measure amounts of food; just as 100 pounds of brick might weigh the same as 100 pounds of feathers, they are wholly incomparable, and would never be substituted for one another.

If we decide to use calories as our basis for measuring (or planning) weight loss, then we are assuming that, all things equal, net energy loss is the primary driver of said weight loss. All things are never equal, as I will discuss briefly, but I do think this is a valid assumption.

This is, in essence, the first law of thermodynamics. It states that energy cannot be created or destroyed–i.e., the total change in energy equals the energy entering the system (read: food) minus the energy exiting the system (read: exercise, basal expenditure, etc.) This cannot be argued.

What can be argued is whether or not an energy deficit is the primary driver of weight loss, or if an energy excess is the primary driver of weight gain. If you’re gaining weight, are you necessarily eating too much or exercising too little? This is not always the case, as many will agree: “I’m on a diet, but I gain weight just by looking at food!”

To me, citing the first law of thermodynamics—or net energy balance in general—is akin to stating: “Why is Bill Gates so rich? Because he makes more money than he spends.” Sure, okay, but how?

So, thus arises my first issue with Gemmell’s advice: that the first step to weight loss is calculating your basal metabolic rate, and then you just need to accumulate a slight deficit for a long period of time. The problem with this methodology is there is no discussion of where those calories should come from, or what forms of exercise ought to be done, if any. The picture is entirely too simplistic. To carry on the money analogy: if one wants to make more money, and you tell them to just “cut their spending,” they could just stop paying rent and would be set. Except that doesn’t work.

Indeed, that’s an exaggeration, and most people aren’t that silly, but in diet and exercise people do silly things that are often counterproductive to true health. (Let us not forget: weight loss and health are not often one in the same.)

You don’t have to make huge changes; just pay a bit more attention, and whittle away a few calories when you can. It all adds up. By the way, some things may surprise you in terms of their fat and sugar content, despite seeming to be “healthy” (and indeed being basically good for you). Fruit, for example, has a lot of sugar, and nuts have a lot of fat. Coconut is pretty heavy, calories-wise, and many muesli/breakfast bars can rival chocolate for their calorie content. There are healthier options available; your supermarket may have a healthy foods section, but still check the label.

It is absolute silliness to suggest to someone to avoid fruit, nuts, or coconuts because of their calorie content alone—they are some of the most healthful foods one can find. Nuts are quite ketogenic, ridiculously nutrient dense, and hard to overeat in reality; fruits are equally nutrient packed, and indeed quite heavy on sugar. Both ought to be moderated, but certainly not to attain a caloric deficit. Cut the soda, alcohol, and bread before almonds or blueberries.

I have similar complaints about using physical activity for the exclusive goal of “calorie burning.”

Go at a reasonable pace. You don’t need to run, but swing your arms. Move with purpose. You can easily cover three miles in a total of 60 minutes (broken up during the day if necessary), and you’ll likely burn 150 calories or more. Your Watch will tell you how you’re doing, and if you need to burn more calories in the same amount of time, try walking a bit faster, or take an uphill route. Just don’t push yourself too hard.

Why? Why should I go at a reasonable pace? Why should I not push myself too hard? I suppose if one gets genuine joy from running for a full hour every day of the week simply to create an energy deficit equal to a can of Coca-Cola instead of just not drinking the Coca-Cola, by all means, carry on. However, I’ve always counted exercise as a vital part of a physical practice that leads to health and longevity, and this is not gained by plodding along for hours, miserable. And certainly don’t do this:

Keeping your brain occupied makes exercise go faster. Listen to music, or podcasts. Watch TV. If you’re on a stationary bike, read a book or your Kindle. I have my laptop set up on my indoor bike. Just find something that distracts you a bit.

Saying “keeping your brain occupied makes exercise go faster” is almost literally calling exercise “mindless,” which almost offends me.

If you do choose to exercise, attack it with the same mindfulness with which you would attack a nightly meditation practice, or a yoga session; the goal is not to just “get it done.” If you can’t find a movement practice that you enjoy and your only goal is weight loss, then congratulations, you never have to run another step in your life.

It’s not a sure-fire weight loss approach anyway; the American Heart Association has formally stated: “It is reasonable to assume that persons with relatively high daily energy expenditures would be less likely to gain weight over time, compared with those who have low energy expenditures. So far, data to support this hypothesis are not particularly compelling.” Indeed, exercise (“training,” as I would call it) is crucially important for long-term health, but not for weight management.


Since this post is has accidentally transformed into a “my thoughts on how to lose weight” post, I’ll do my best to conclude with some actionable advice.

Do I think calorie counting is critical, or even necessary, for weight loss? I truly don’t, certainly not for long-term, sustainable weight loss. The best possible solution that I’ve found is working to change the way your body processes and partitions the fuel it is given. It is sometimes said: obesity is a disorder of inappropriately accumulating fat, not a disorder of eating too many calories.

So, how does one reduce fat accumulation if calories aren’t the answer? It turns out that there is but one way for fat to be deposited in your body: the hormone insulin, a hormone released by the pancreas when (and only when) carbohydrates enter the bloodstream (unless, of course, you are diabetic, but that’s another conversation.)

I’m not going to lecture on beta cells and insulin resistance, but it’s certainly a topic worth investigating if weight loss, obesity, or diabetes is on your mind. Instead, I can tell you why I think we get fat: excess insulin caused by excess carbohydrate consumption. Changing nothing else while eliminating all sugar consumption, “simple” carbohydrates like bread and pasta, sweeter fruits and juices, and reducing overall carbohydrate intake will result in fat loss.

Generally, I also advocate for an increase in fat consumption and a moderate protein intake. Indeed, that means my diet includes a lot of meat, chicken, fish, eggs, nuts, dairy, avocados, olive and coconut oils, berries, and vegetables galore. Admittedly, it looks a lot like a Paleo model, though I don’t call it that anymore. The word ketogenic comes to mind as well.


The subjects I’ve discussed here are detailed and complex enough to write a book on, and many have. I can’t hope to give you every detail you might want in this post alone (though you know how to contact me if you have questions.)

The takeaway should be this: you don’t have to be a slave to the numbers to get the results you want. I would in fact argue the opposite: succumbing to the conventional wisdom of weight loss will only lead to unsustainable habits and disappointment. Take the long road, and be in it for life.

A parting note: I would encourage you all to look past the number on the scale. Weight matters, in both health and our own personal journeys, but there is so much more to our bodies than that. The human body is indeed a remarkable machine, designed to live well past a century, and it is the tragedy of modern medicine that we all have not yet been convinced of that. When you set out to make a change, do it for your health, physicality, and longevity, not the number you see on the scale. And to do that, we’re going to have to dig a little deeper than “calories.”