- What is TDEE and how is it calculated?
- TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in 24 hours. It is calculated by first determining your Basal Metabolic Rate (BMR) using an equation like Mifflin-St Jeor, then multiplying by an activity factor (1.2 for sedentary to 2.0 for athletes). TDEE includes BMR (60-70%), the thermic effect of food (8-15%), exercise activity (5-10%), and non-exercise activity thermogenesis or NEAT (15%).
- What is the difference between BMR and TDEE?
- BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to maintain basic life functions like breathing, circulation, and cell production. TDEE (Total Daily Energy Expenditure) includes your BMR plus all additional calories burned through physical activity, digestion, and daily movement. TDEE is always higher than BMR — typically 1.2x to 2.0x depending on activity level.
- Which BMR equation is most accurate?
- The Mifflin-St Jeor equation is considered the most accurate for the general population, with studies showing it predicts BMR within ±10% for about 82% of non-obese individuals. The Katch-McArdle formula can be more accurate for lean individuals who know their body fat percentage, as it uses lean body mass instead of total weight.
- How many calories should I eat to lose weight?
- To lose weight, eat 15-25% fewer calories than your TDEE. A moderate deficit typically translates to losing 0.5-1 pound per week. For example, if your TDEE is 2,400 calories, eating 1,800-2,040 calories per day would create a healthy deficit. Deficits larger than 25% can lead to muscle loss and metabolic adaptation.
- What should my macros be for weight loss?
- For weight loss, a common macro ratio is 40% protein, 35% carbs, 25% fat. Higher protein (0.7-1.0g per pound of body weight) helps preserve muscle mass during a calorie deficit and increases satiety.
- What should my macros be for muscle gain?
- For muscle gain, aim for a 5-20% calorie surplus with macros around 30% protein, 45% carbs, 25% fat. Protein should be 0.7-1.0g per pound of body weight. Carbohydrates fuel workouts and recovery.
- How much protein do I need per day?
- For general health: 0.36g/lb (0.8g/kg) is the RDA minimum. For weight loss while preserving muscle: 0.7-1.0g/lb. For muscle building: 0.7-1.0g/lb. Athletes and those in a large deficit may benefit from up to 1.2g/lb.
- What activity level should I choose?
- Choose Sedentary if you have a desk job and don't exercise. Lightly Active for 1-3 light workouts/week. Moderately Active for 3-5 workouts/week. Very Active for hard daily exercise. Most people overestimate — when in doubt, choose one level lower.
- How accurate are TDEE calculators?
- TDEE calculators have a typical margin of error of ±10-15%. Use the result as a starting point and adjust based on real-world results after 2-3 weeks of consistent tracking.
- What is NEAT and why does it matter?
- NEAT (Non-Exercise Activity Thermogenesis) is energy burned through daily movement excluding exercise — walking, fidgeting, standing. It accounts for ~15% of TDEE and can vary by up to 2,000 cal/day between people. Increasing NEAT is one of the most effective weight management strategies.
- What is the thermic effect of food?
- TEF is the energy required to digest food. Protein uses 20-30% of its calories for digestion, carbs 5-10%, and fat 0-3%. TEF accounts for 8-15% of TDEE, which is why high-protein diets are effective for weight loss.
- How often should I recalculate my TDEE?
- Recalculate every 4-6 weeks or after every 5-pound weight change. As you lose weight, your BMR decreases, so your calorie targets need updating to prevent plateaus.
- Can I lose fat and build muscle at the same time?
- Yes — body recomposition is possible for beginners, overweight individuals, and those returning to training. Eat at or slightly below maintenance with high protein (1.0g/lb), train with resistance 3-5x/week, and sleep 7-9 hours.
- What is metabolic adaptation?
- Metabolic adaptation is your body reducing energy expenditure during prolonged calorie restriction. Counter it with diet breaks every 8-12 weeks, refeed days, avoiding extreme deficits, and maintaining muscle mass through resistance training.
- Should I eat back my exercise calories?
- If you already factored exercise into your activity level, no. If you used 'Sedentary' and exercise separately, eating back 50-75% of estimated exercise calories is reasonable — fitness trackers overestimate burn by 20-50%.
