Weight change comes down to calories in versus calories out (CICO). Most people underestimate intake by 20-40% - every bite, drink, cooking oil, and condiment counts.
#Your Total Daily Energy Expenditure (TDEE)
- BMR (60-75%) - calories burned at rest just to keep organs running
- NEAT (15-30%) - daily movement like fidgeting, chores, walking to the bathroom
- TEF (10%) - energy needed to digest food
- Exercise (5-10%) - your actual workouts; often the smallest component
#The Basic Math
- Calories in > out = weight gain
- Calories in < out = weight loss
- Calories in = out = maintenance
One pound of fat ≈ 3,500 calories. A 500 cal/day deficit ≈ 1 lb/week loss. But your body isn't a calculator - metabolic adaptation, water weight, hormones, sleep, and stress all affect results.
#How to Use This
- Track your baseline - log what you normally eat for a week without changing anything
- Calculate your TDEE - use the FitJourney calculator above for a starting estimate
- For weight loss - aim for 300-500 calories below TDEE; don't go below 1,200 (women) or 1,500 (men); aggressive deficits backfire through muscle loss and binge eating
- Adjust based on results - no change after 2 weeks? Reduce by 100-200 cal; losing too fast? Add some back; track the trend, not daily fluctuations
#Mistakes to Avoid
- Not counting liquid calories (a smoothie can be 600 cal)
- Overestimating exercise burn
- Ignoring portion sizes
- Weekend amnesia - Saturday and Sunday count too