What TDEE means
Total Daily Energy Expenditure is the sum of every calorie your body burns in a 24-hour period. It includes:
- BMR (Basal Metabolic Rate) — calories burned just keeping you alive (breathing, circulation, brain function). This is ~60–70% of TDEE for most people.
- NEAT (Non-Exercise Activity Thermogenesis) — calories from walking, fidgeting, standing, daily movement. ~15–25% of TDEE.
- EAT (Exercise Activity Thermogenesis) — calories from intentional exercise. ~5–15% depending on training volume.
- TEF (Thermic Effect of Food) — calories burned digesting food, especially protein. ~10% of intake.
The calculator above uses the Mifflin-St Jeor equation for BMR and applies an activity multiplier — the most validated approach for active adults under 60.
How to use TDEE for weight loss
For weight loss, you want to eat below TDEE. The size of the deficit determines the rate:
- Mild deficit (~250 cal/day) — about 0.5 lb/week. Easy to maintain, minimal hunger spikes, minimal muscle loss.
- Moderate deficit (~500 cal/day) — about 1 lb/week. The sweet spot for most people without medication.
- Aggressive deficit (~750 cal/day) — about 1.5 lb/week. Harder to sustain, higher risk of muscle loss without high protein.
- GLP-1 deficit — often naturally larger than this because the medication suppresses appetite. The real risk on a GLP-1 isn't eating too much; it's eating too little protein.
Larger isn't better. Beyond ~750 cal/day, hunger, fatigue, and lean mass loss escalate without proportionally faster fat loss.
Why protein matters more than the deficit
On any deficit — and especially on a GLP-1 — the variable that protects you from losing muscle is protein intake. Most clinicians recommend 0.7–1.0 grams of protein per pound of goal body weight per day. Use our protein calculator to set a specific target.
What TDEE doesn't capture
TDEE estimates are calibration tools, not laws of physics. Real-world individual TDEE varies by ±200–300 cal/day from any formula. Use the number as a starting point, then adjust based on what your weight actually does over 2–4 weeks. If you're losing too fast, eat more. If nothing's moving, eat less.