Weight‑Loss 101: Creating a Sustainable Calorie Deficit Without Losing Muscle
A 500‑calorie daily deficit equals ~1 lb (0.45 kg) of fat per week—if you keep protein high and strength‑train.
Hook
**Cutting 3 500 kcal ≈ 1 lb (0.45 kg) fat—spread that over 7 days and it’s just a 500‑calorie gap per day.**
TL;DR
- Target deficit: 15‑25 % below maintenance (≈ 300‑600 kcal)
- Protein: ≥ 1.6 g kg‑¹ to preserve lean mass
- Aim for 0.5‑1 % body‑weight loss per week
What is a calorie deficit?
Eating **fewer calories than you burn (TDEE)** so stored fat supplies the energy gap. Components of TDEE: BMR ≈ 60 %, NEAT ≈ 15 %, exercise ≈ 10 %, TEF ≈ 10 %.
Energy‑balance science
- **1 kcal** = heat to raise 1 kg water 1 °C.
- Fat tissue stores ~9 kcal/g; glycogen/water loss skews early scale drops.
- Adaptive thermogenesis can lower BMR 5‑10 % when dieting hard.
Building the deficit
| Method | Typical kcal cut |
|--------|------------------|
| Food swaps (sugary drinks → zero‑cal) | 150‑250 |
| Portion control (50 g rice → 30 g) | 100 |
| Extra 8 000 steps/day | 250‑300 |
| Strength + HIIT 3× wk | 200‑300 |
Protein & muscle retention
- 1.6‑2.2 g kg‑¹ body‑weight supports MPS.
- Distribute across ≥ 4 meals (0.4 g kg‑¹ each).
- Combine with progressive‑overload training.
Practical tips
- Track intake for 2 wks to find true maintenance.
- Fill half your plate with high‑volume veg (≤ 30 kcal/100 g).
- Sleep ≥ 7 h—sleep restriction raises ghrelin & cravings.
Myth vs fact
| Myth | Fact |
|------|------|
| “Carbs make you fat.” | Surplus calories—any macro—store as fat.
| “You must eat every 3 h.” | Meal frequency doesn’t beat total calories/protein.
| “Fat‑loss shakes melt fat.” | No supplement overrides energy balance.
Take‑home message
Calculate maintenance, trim 15‑25 %, keep protein high, lift weights; adjust every 3‑4 weeks as weight drops.
References
1. Hall KD et al. *Lancet Diabetes Endocrinol* 2022.
2. Helms ER et al. *J Sports Med* 2019.
3. NIH Body Weight Planner, 2024.