Caloric Balance: Cause or Effect?
Losing weight is so simple. You just have to consume fewer calories than you burn.
🤦. A classic. Everyone knows it, and it’s so logical. But this advice is about as helpful as telling an alcoholic to simply drink less: technically correct, but pretty pointless.
The tragedy of this old wisdom is that it implies a direction of cause and effect, and then wonders why it doesn’t work in the end.
I’d like to invite you to shift perspective, and interpret calorie consumption as an effect rather than a cause. With this line of thinking it becomes much easier for me to explain why weight loss so often fails:
Do I gain weight because I eat a lot, or do I eat a lot because I’m gaining weight?
Here’s the reasoning:
- What the body does with food is determined by hormones, above all: insulin. One common recommendation in nutritional advice - you’ve probably heard it - is “3 meals a day, with 3 snacks in between”. And at the base of the food pyramid: “Plenty of whole grains” (i.e. One of the three macronutrients — typically sugars, starches, or (indigestible) fibre. → more). This diet almost certainly produces a persistently mildly or strongly elevated insulin level. That means the energy taken in is converted to fat and “locked away” by the body: As long as insulin is elevated, the body cannot use its own fat stores as an energy source.
But if the body stores all this energy in a way it can’t mobilise (as long as insulin stays high), the next hunger-attack follows entirely logically. And that’s legitimate: the body has no energy freely available, so new food must fill the gap. A vicious cycle.
The result is that you consume more calories than you burn. Insulin reliably ensures that a portion of the food is stored and not released again (as long as insulin remains elevated).
A comparison: someone who fills an extra 5-litre fuel can every time they refuel their car and locks it in the trunk will, mathematically, increase the car’s “consumption” (calculated from the amount pumped) and its weight. The car takes in more fuel than it burns. But it doesn’t help to fill up less, if 5 litres of reserve keep getting stashed away each time.
Reversing Cause and Effect
Speaking of cause and effect: here are two alternative versions of the diet described above. Notice the time the insulin level is elevated (the blue area) compared to the chart above.
In the first alternative, the same foods are eaten, but restricted to a 4-hour window via intermittent fasting, rather than spread evenly throughout the day as before.
The second alternative is a low-carbohydrate diet: Energy comes predominantly from fat. The effect on insulin is clearly visible: the curve is lower, so the (blue) area under the curve is significantly smaller. Due to the gradient at the lower end it’s barely visible.
An important note: the bottom edge of the blue area does not start at zero, but above the fat-burning zone. It represents the duration and intensity of the elevated insulin level. All charts in this article show meal plans with the same caloric content.
The Law of Thermodynamics
Thermodynamics is constantly wheeled out to justify the caloric balance argument. There’s no arguing with that. But the direction of cause and effect is another matter entirely: the body is ultimately not a physical combustion engine, but a hormonally controlled biological system. And with the right (or wrong) food, it’s very easy to steer which hormones call the shots — and whether weight is gained or lost.
The elephant in the room is insulin: when insulin is elevated, it is impossible for the body to access its fat reserves. What matters is both duration and intensity, in combination. When is insulin elevated? Try it out, right next door in the simulator.
