Total Daily Energy Expenditure (TDEE)

Total daily energy expenditure (TDEE) is the sum of everything the body spends energy on in 24 hours. It has four components:

1. Basal metabolic rate (BMR): resting energy — the largest share, ~60–70% (see bmr-estimation).
2. Thermic effect of food (TEF): energy to digest and process meals — ~10% of intake (protein has the highest TEF).
3. Exercise activity thermogenesis (EAT): structured workouts (see exercise-and-calories).
4. Non-exercise activity thermogenesis (NEAT): all other movement — fidgeting, walking, posture, daily tasks — highly variable between people and a major reason two people of the same size differ in needs.

The simplest estimate multiplies BMR by an activity factor (see activity-factors): TDEE = BMR × activity factor. The biggest source of error is overestimating activity, which inflates the calorie target. Because every method is an estimate, the reliable approach is to use it as a starting point, then adjust based on a 10–14 day body-weight trend: if weight is stable, the estimate matched maintenance; if it drifts, recalibrate the target. TDEE is also dynamic — it falls somewhat as you lose weight (lower mass and adaptive reductions in NEAT/BMR).

• TDEE = BMR + TEF + exercise activity + non-exercise activity (NEAT).
• BMR ~60–70%; TEF ~10% of intake; NEAT highly variable.
• Quick estimate: TDEE = BMR × activity factor.
• Overestimating activity is the main error source.
• Validate against a 10–14 day weight trend; TDEE drops as you lose weight.

• bmr-estimation — the resting baseline.
• activity-factors — multipliers to reach TDEE.
• calorie-targets — turning TDEE into fat-loss/gain targets.
• exercise-and-calories — exercise's contribution to expenditure.