Question 1

What is Total Daily Energy Expenditure (TDEE)?

Accepted Answer

Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day, including all physical activity. It is calculated as BMR × Physical Activity Level (PAL) multiplier, following WHO/FAO/UNU 2004 guidelines. TDEE is the critical number for nutrition planning: eating at TDEE maintains your current weight; eating below TDEE produces fat loss; eating above TDEE produces weight gain.

Question 2

Which TDEE formula is the most accurate?

Accepted Answer

For general adults, the Mifflin-St Jeor equation (1990) is the gold standard recommended by the Academy of Nutrition and Dietetics (AND) and ACSM — it predicts BMR within ±10% for most people. For athletes with known body fat percentage, the Cunningham formula is more accurate because it uses lean body mass directly and avoids overestimating BMR in high-muscle individuals. The Oxford Equations (WHO 2005) are validated across diverse world populations and require only weight, making them robust when height is unavailable.

Question 3

How do I use the Reverse TDEE calculator?

Accepted Answer

The Reverse TDEE calculator back-calculates your actual TDEE from real tracking data. Enter your start weight, end weight, the number of weeks tracked, and your average daily calorie intake. The formula is: Estimated TDEE = Average Intake − (Weight Change × 7,700 ÷ Tracking Days). A negative weight change (loss) means your TDEE was higher than your intake. Use 4–12 weeks of consistent data for reliable results — short periods may be skewed by water retention.

Question 4

What are macros and how are they calculated?

Accepted Answer

Macronutrients (macros) are protein, carbohydrates, and fat — the three energy-providing nutrients. The Macro Calculator converts your calorie target into grams of each macro based on your chosen diet style. Protein: 4 kcal/g. Carbohydrates: 4 kcal/g. Fat: 9 kcal/g. Five evidence-based macro distributions are available: Balanced (30/40/30 P/C/F per ACSM 2016), High Protein (40/30/30 per ISSN 2017), Low Carb (30/25/45), Ketogenic (25/5/70 per Volek & Phinney), and High Carb (20/60/20 per IOC 2011 for endurance athletes.

Question 5

How long will it take to reach my goal weight?

Accepted Answer

The Weight Goal Planner calculates your timeline based on the physics of fat loss: 1 kg of body fat ≈ 7,700 kcal. The formula is: Days = |Weight Difference| ÷ Rate (kg/week) × 7. At 0.5 kg/week (the recommended moderate rate), losing 5 kg takes 10 weeks. The safe recommended range is 0.25–1.0 kg/week. Faster rates risk lean mass loss and metabolic adaptation. The planner flags when target calories would fall below safe minimums (1,500 kcal/day for males, 1,200 kcal/day for females).

Question 6

What is the Cunningham formula and when should I use it?

Accepted Answer

The Cunningham formula (1980), endorsed by the International Society of Sports Nutrition (ISSN), calculates Resting Metabolic Rate from Lean Body Mass: RMR = 500 + 22 × LBM(kg). It is the most accurate formula for athletes and individuals with known body fat percentage, because it uses actual muscle mass instead of body weight proxies. It requires a measured body fat percentage — ideally from DXA, BodPod, or calibrated skinfold calipers. Do not use body fat estimates from bathroom scales for this formula, as their accuracy is insufficient.

Question 7

What are the WHO/FAO Physical Activity Level (PAL) multipliers?

Accepted Answer

PAL multipliers from WHO/FAO/UNU 2004 convert BMR to TDEE: Sedentary (×1.2) — desk job, little/no exercise. Lightly Active (×1.375) — exercise 1–3 days/week. Moderately Active (×1.55) — exercise 3–5 days/week. Very Active (×1.725) — hard exercise 6–7 days/week. Extra Active (×1.9) — physical job plus daily training. Most people overestimate their activity level. Non-Exercise Activity Thermogenesis (NEAT) — fidgeting, walking, standing — can add 200–800 kcal/day and is the largest untracked variable in TDEE estimation.

Type	Description
Standard TDEE	Total Daily Energy Expenditure
Macro Split	TDEE with macro breakdown
Activity Comparison	TDEE at all activity levels

Type	Description
Standard TDEE	Total Daily Energy Expenditure
Macro Split	TDEE with macro breakdown
Activity Comparison	TDEE at all activity levels

TDEE Calculator: Guide

What is TDEE?

Formula

Tips

How to Use

Real-World Applications

FAQs

Are the results accurate?

Why does a small input change affect the output significantly?

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