Calorie deficit: how to lose weight safely

Losing weight is, at its core, an energy equation: you lose weight when you spend more calories than you take in. That "less" is the calorie deficit — the one mechanism that actually moves the scale, whatever diet you follow.

The deficit math

Each kilo of body fat stores about 7,700 kcal. From your desired pace:

daily deficit = (kg per week × 7,700) ÷ 7

To lose 0.5 kg/week: (0.5 × 7,700) ÷ 7 ≈ 550 kcal/day. Eat that much below your maintenance (TDEE).

Step-by-step example

Maintenance (TDEE) of 2,200 kcal, target 0.5 kg/week:

• Deficit: 550 kcal/day
• Target: 2,200 − 550 = 1,650 kcal/day

Go slow

Aggressive cuts (over ~1 kg/week) burn muscle, spike hunger and rarely last — the road to yo-yo dieting. A moderate deficit preserves lean mass and is far easier to keep up.

It's not just cutting food

Prioritize protein (keeps muscle and fullness) and add activity, which raises your burn without eating even less. Strength training best protects lean mass while dieting.

FAQ

Why doesn't the scale drop every day? Weight fluctuates with water and salt. The 7,700 kcal rule is a useful average — watch the multi-week trend.

Is there a food that "speeds up" fat loss? Not meaningfully. Total calorie balance over time is what matters.