What Happens
AI calculates your maintenance calories at 2,450. You eat exactly 2,450. After 4 weeks, you've gained 3 pounds — you thought you were at maintenance. Or: AI puts you on a 2,000-calorie cut. After 2 weeks, you're exhausted, starving, and performance has tanked because the deficit was too aggressive for your actual TDEE.
Why It Happens
AI uses equations (Mifflin-St Jeor, Harris-Benedict) that predict caloric needs based on population averages. YOUR actual metabolism can differ by 200-400 calories from ANY equation. Factors no equation captures: NEAT (non-exercise activity thermogenesis), metabolic adaptation history, hormonal variation, and individual metabolic rate.
How to Avoid It
Treat AI's calorie calculation as a STARTING POINT, not a target:
Calculate my estimated TDEE. I understand this is an approximation. After I track my intake at this level for 2 weeks, I'll tell you my weight trend and we'll adjust. Start conservative.
The gold standard: Track your weight daily (morning, after bathroom, before food), take the weekly average, and compare week-over-week. If the weekly average changes in the direction you want at the right rate, your calories are right. If not, adjust by 200 calories and wait another 2 weeks. Use MacroFactor to automate this process.