Module

Understanding Energy Estimates

This module builds the logic of energy estimates in four steps: the concept of a calorie, resting metabolism (BMR), total daily expenditure (TDEE), and the uncertainty in the estimates.

In this module

  • You can explain what a calorie measures and that food energy comes from macronutrients
  • You can define BMR and calculate an estimate with the Mifflin-St Jeor formula
  • You know the role of the activity factor in TDEE estimates and what the 1.2-1.9 range means
  • You understand that every estimate carries a margin of error and results should be read as ranges

What this module teaches

Behind every calorie calculator you meet on the internet sit a few simple formulas. This module takes those formulas out of the black box: step by step, you see what a calorie is, why the body spends energy even at rest, how daily movement multiplies that expenditure, and why all of this maths produces estimates rather than exact results. Only basic arithmetic is used throughout; the aim is not to memorise formulas but to show the logic behind the numbers.

The logical order of the lessons

The first lesson lays the ground: a calorie is a unit of energy, and energy balance is the relationship between what comes in and what goes out. The second lesson focuses on the biggest item on the outgoing side, resting metabolism, and introduces the Mifflin-St Jeor formula. The third lesson multiplies that value by an activity factor to reach a total daily estimate. The final lesson asks the most important question: how much can you trust these numbers? We placed the uncertainty lesson last, because using a tool without knowing its limits can be more misleading than not using it at all.

Lessons

First published: 2026-08-12Last reviewed: 2026-08-12Editorial status: working editionReport an error