Every diet that works — keto, fasting, low-fat, all of them — works through the same mechanism: a calorie deficit, meaning you consume less energy than you burn. The method is negotiable; the deficit is not.
The practical challenge is twofold: knowing your numbers, and staying in the deficit for enough weeks to matter. Both are tracking problems, and both got much easier with AI logging.
Calculate your deficit in 3 steps
- 1Estimate maintenance calories: body weight (kg) × 31–33 for moderately active people gives a workable starting estimate.
- 2Subtract 300–500 kcal: enough for ~0.25–0.5 kg of fat loss per week without wrecking energy, mood or muscle.
- 3Verify with reality: track intake and weight for two weeks. If weight doesn't trend down, your true maintenance is lower — adjust and continue.
Why bigger deficits backfire
Crash deficits (800+ kcal) feel productive for two weeks, then collapse: hunger hormones surge, energy tanks, muscle loss accelerates and the diet ends in a rebound. A moderate deficit you can hold for twelve weeks beats an aggressive one you abandon in three. Sustainable is not a consolation prize — it is the winning strategy.
The habit that keeps you in deficit
People who track their food consistently lose significantly more weight than those who don't — not because tracking burns calories, but because untracked eating drifts upward invisibly. A handful of nuts here, a splash of oil there, and the deficit quietly disappears. Five-second photo logging keeps the drift visible while it is still small.
How to run your deficit with MacroMora
- 1
Set a weight-loss goal
MacroMora calculates your daily calorie target with a sensible built-in deficit.
- 2
Photo-log everything
Every meal and snack gets a five-second photo log — the consistency that makes deficits real.
- 3
Watch the daily budget
See remaining calories at any moment, so evening decisions are informed instead of hopeful.
- 4
Trust the weekly trend
Daily weight noise is meaningless; MacroMora's weekly charts show the trend that matters.
Free to download on iPhone & iPad
Frequently asked questions
How big should my calorie deficit be?
300–500 kcal below maintenance for most people — enough for steady fat loss while keeping energy, workouts and adherence intact.
Why am I not losing weight in a deficit?
Almost always: the deficit exists on paper but not in reality — untracked bites, oils and drinks close the gap. Two weeks of complete photo logging usually reveals it.