The Science of Losing 5 kg
One kilogram of body fat stores approximately 7,700 kcal of energy. To lose 5 kg of fat, you need to create a total caloric deficit of roughly 38,500 kcal. The only variable you control is how fast you create that deficit.
• 250 kcal/day deficit → ~10 weeks (0.5 kg every 2 weeks)
• 500 kcal/day deficit → ~11 weeks (0.5 kg/week)
• 750 kcal/day deficit → ~7 weeks (0.75 kg/week)
• 1,000 kcal/day deficit → ~5–6 weeks (1 kg/week — challenging, not recommended for most)
A deficit of 500 kcal/day is the sweet spot for most people — meaningful progress without triggering excessive hunger, muscle loss or metabolic adaptation.
Step 1: Calculate Your TDEE
Your TDEE (Total Daily Energy Expenditure) is the number of calories you need to maintain your current weight. Everything below TDEE is your deficit. Use our BMI and TDEE calculator to find your exact number.
A rough estimate: multiply your body weight in kg by:
- × 26–28 if sedentary (desk job, little exercise)
- × 30–32 if lightly active (3–4 workouts/week)
- × 34–36 if very active (physical job or daily training)
Step 2: Create Your Deficit Through Diet
Exercise is important for health, but diet is the more reliable driver of a caloric deficit. It's much easier to not eat 500 kcal than to burn 500 kcal through exercise (which takes about 45–60 minutes of running).
Practical ways to create a 500 kcal/day deficit without feeling deprived:
- Eliminate or reduce liquid calories (alcohol, juice, sugary coffee drinks)
- Replace refined carbs (white bread, pasta, rice) with high-volume, low-calorie options (vegetables, legumes)
- Increase protein to 1.8–2.2 g/kg — this reduces hunger significantly
- Use smaller plates and eat slowly — hunger signals lag ~20 minutes behind eating
Step 3: Add Resistance Training
While cardio burns more calories per session, resistance training has a superior long-term effect on body composition. Muscle tissue burns more calories at rest, and maintaining (or building) muscle during weight loss means the weight you lose is predominantly fat rather than muscle.
Aim for 2–3 sessions per week of full-body resistance training. This doesn't require a gym — bodyweight exercises (push-ups, squats, lunges, rows) are highly effective.
Step 4: Optimize Sleep and Stress
Two under-appreciated factors in weight loss:
- Sleep: sleeping less than 7 hours increases ghrelin (hunger hormone) by up to 24% and decreases leptin (satiety hormone). Sleep deprivation makes maintaining a deficit significantly harder.
- Stress: chronic stress elevates cortisol, which promotes fat storage (especially visceral fat) and triggers cravings for high-calorie foods.
What to Expect Week by Week
Week 1–2: Faster initial loss (1–2 kg) driven largely by water and glycogen depletion — not fat. Don't be fooled by a big early drop, or discouraged when it slows down.
Week 3–10: Steadier fat loss of approximately 0.5 kg/week. Progress may plateau for 1–2 weeks — this is normal and often reflects water retention masking fat loss.
Throughout: Body composition continues improving even when the scale stalls, as fat is replaced by muscle.