1 Calorie ≠ 1 Calorie

We're doctors, not mathematicians

The best survival show on TV right now (and it’s not even close) is Alone on the History Channel. 10 people are dropped as deep as deep goes into the remote wilderness, usually in an arctic climate just before winter hits. Each is allowed to bring ten items. That’s it. Once you’re dropped off you must: build a shelter capable of keeping you warm, find food, and either avoid or hunt the animals of the forest. Whoever lasts the longest wins. In season 8 the winner was this guy:

Roland Welker. He lasted 100 days. His secret? He got a “big-game” kill. He shot a Musk Ox with a bow and finished it off with his hunting knife because he couldn’t wait for it to bleed out, fearing that other wild animals would smell the blood and try to steal his kill. That Musk Ox provided him with enough calories to out last all of the other contestants. Even so, by the end of the 100 days Roland had lost around 20% of his body weight.

The average contestant on Alone loses more than 20% of their body weight if they last over a month. The average winner lasts more than two months. In the nine seasons Alone has been on so far, not a single contestant has maintained their weight. Building a shelter, hunting, foraging, fishing, shivering in freezing rain…These activities expend lots of energy. Put differently, these activities consume lots of calories. So many calories in fact, that even trained survival experts are uncapable of finding enough food in the wild to replace them, and thereby maintain their weight. To be fair, humans have been pack animals for millions of years - we’re not built to run solo.

A calorie is a measure of energy. 1 calorie is the amount of energy you get by eating a specific amount of a specific type of food or drink. 1 gram weight of watermelon will have a different amount of calories than 1 gram weight of avocado because they deliver to your body a different amount of energy.

Some contestants on alone have done surprisingly well not because they succeeded at finding food (read: calories) in the wilderness, but because they brought a ton of extra calories with them. If you’re wondering, no you aren’t allowed to bring food as one of your ten items. I’m referring to fat stores. When you eat food it gives you calories (read: energy). You can use that energy the same day by walking around, exercising, picking up your child, going to work or even sleeping (your brain consumes lots of calories while you sleep). Or, if you don’t use that energy during the course of your day, then it will get stored as fat. Another way to think about fat is that it is “potential energy”. Fat is like an extra tank of gas you can lug around. If you aren’t driving through the desert you won’t need it and it will just take up space. But, in a pinch, if your tank goes empty you can use the reserve until you get to a gas station.

With that background in mind, not all calories are made equal.

I can practically hear the words being shouted in the voice of a grumpy old man from a Disney movie: “It’s all about calories in and calories out. If you use more calories than you take in then you will lose weight!”

Sure…that’s what the math says.

And so does the Mayo Clinic:

Your weight is a balancing act, but the equation is simple: If you eat more calories than you burn, you gain weight. And if you eat fewer calories and burn more calories through physical activity, you lose weight.

They’re not wrong, but the problem is that statements like these are always made within the context of diet. When it comes to dieting, calories come with a multitude of characteristics.

Saying all calories are the same because they provide the body with an equivalent amount of energy is sort of like saying a giant land-moving tractor is the same thing as 250,000 teaspoons because they can displace the same amount of dirt.

Practically speaking, if your goal is to dig a hole (in our analogy: lose weight) you’d sure rather have the tractor than 250,000 teaspoons.

Think of food like a tool, and think of your body like a project. You need to match your tools to your project. Your project might be: trying to get better sleep. It might be: improving athletic endurance. Or, it might be: trying to lose weight. Whatever your project is you need to use the right tools to build it out.

If you are trying to lose weight sustainably and not feel miserable the whole time then possibly the most important thing you can do is consume calories that make you feel full (satiated) for longer. Anyone can just do a water fast for a few weeks and lose weight - but that’s not sustainable and you’ll feel like shit. Worse still, you’ll almost certainly end up putting the weight back on when you’re done. But, by eating the right type of calories you will remove a huge portion of the temptation to overeat by altering your hunger patterns. Consider the following.

1 large pizza has the same amount of calories as 3 dozen eggs:

Everyone knows someone who can eat a large pizza, or at least half a pizza (4 pieces). But have you ever seen someone eat 3 dozen eggs? 18 even? Not only will the eggs make you full sooner and with fewer calories - they will keep you full for longer.

Carbohydrates actually act like an appetite stimulant. Consuming a carb heavy meal will eventually make you feel full, but then not only will you be hungry again in as little as an hour, you will actually feel like you need to eat more at your next meal. This is because carbs don’t provide lasting satiety.

So, if you knew that eating carbs would not only make you hungry more often but also increase the amount your body feels like it wants to eat to get full - what would you think about a headline like this?

They may be right on the math, but they couldn’t be more wrong on the execution. The reason low-carb dieting works so well is because it literally re-writes the code inside your brain that dictates how much and how often you want to eat.

Why are humans so addicted to carbs? What drives us to binge? It all goes back to evolution. Carbohydrates were a rare and precious resource back in the days of hunting and gathering - the way we fed ourselves for literally millions of years (fats and proteins were far more common). If you came across a berry patch it made sense to eat all you could as quickly as possible before other animals discovered them. After all, you didn’t have a refrigerator to store them for later. Humans who binged carbs a million years ago survived better than those who left the berries in the bush. Simple as that.