Calorie counting might not be worth the effort

Tim

08 Apr 2025 — 1 min read

Outside of a lab, it's not possible to get an exact count of how many calories

... are in the food you eat.
... you absorb, use, and/or excrete.
... you expend through metabolic activity and movement.

Why is that?

To precisely measure the amount of energy that a food contains you have to use a tool like a bomb calorimeter. (I don't know about you, but that's not something I have sitting around at home.)

Similarly, if you want to get the most accurate reading on how much energy you're expending over a certain period of time, you'll have to get into an airtight environmental chamber that can measure and record the rate at which your body produces heat. (This measurement strategy is called direct calorimetry.)

What about food labels?

Food labels can give you a general idea of the amount of calories and nutrients that different foods contain, but the numbers that they list are averages. The actual caloric content of the foods is often higher or lower.

What about <insert fitness gadget here>?

Wearable trackers such as smart watches or monitors on exercise machines at the gym offer the least precision in terms of measuring the amount of energy you're burning during an activity. For example, their calculations might be based on laboratory averages, and/or they might not even take your bodyweight into account. (This matters because moving a larger body requires more energy than moving a smaller one.)

The takeaway

Highly detailed calorie counting as a strategy for controlling energy intake has its place. But for many people it is difficult, time-consuming, and relatively inaccurate. So the effort that it requires ultimately outweighs the benefits, especially if you're looking for a sustainable, long-term approach to managing your weight.

How knowing about energy balance can help you save money

The concept of Energy Balance may seem simple, and maybe you've heard it a thousand times already. But it's actually very helpful to come back to when you're trying to make sense of ads nutrition-related information that you come across in your everyday life.

A Note on Water Weight

When it comes to weight management, water tends to make things confusing. Here's why: Water can change body weight independent of energy balance. That can make it seem like Energy Balance isn't working. For example, even if you manage to consistently take in less energy than

Energy Balance

If you're looking to get a better understanding of weight management, it's helpful to start with the concept of energy balance. It comes down to to a fundamental principle of physics (the 1st law of thermodynamics, to be exact): Energy cannot be created or destroyed. In

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