To lose body fat you need to create a calorie deficit between 15% and 25% of your daily caloric needs (TDEE).
Quick example:
- TDEE: 1,900 kcal
- 22% deficit → 1,482 kcal/day
The Nutryon Method (Based on Real Data)
This approach uses:
- Mifflin-St Jeor formula (scientifically validated)
- Adaptive percentage deficit on real TDEE
- Macro distribution according to international guidelines
The calculations shown come from the Nutryon engine, designed to generate personalized nutrition plans based on real data.
What is a Calorie Deficit
A calorie deficit is the difference between the calories you consume and the calories you burn every day. To understand how much to eat to lose weight, you first need to know your real caloric needs.
- If you're in a deficit → you lose fat
- If you're in a surplus → you gain weight
- If you're at maintenance → you maintain weight
Step 1 — Calculate Your TDEE
Your TDEE is your total daily calorie expenditure. It depends on metabolism, physical activity, training and daily movement.
Base formula (Mifflin-St Jeor):
For women: 10 × weight + 6.25 × height − 5 × age − 161
For men: 10 × weight + 6.25 × height − 5 × age + 5
Real Example
A 28-year-old woman, 58 kg, 161 cm, with 4 weekly workouts and an active job:
Estimated TDEE: 1,928 kcal/day
This is the starting point. Everything else depends on this number.
Step 2 — Apply the Correct Deficit
| Approach | Deficit | Result | |---|---|---| | Progressive | 15% | Slow but sustainable | | Balanced | 20–22% | Best balance | | Intensive | 25–28% | Short period only |
Real calculation on the example:
1,928 × 0.78 = 1,504 kcal/day
This is the daily target for a balanced approach.
The Most Common Mistake
Cutting calories randomly — like "I'll eat 1,200 kcal" — without knowing your real caloric needs.
The result is almost always:
- Loss of muscle mass
- Slowed metabolism
- Unsustainable plan after 2 weeks
The deficit must be a percentage of your real TDEE, not a randomly chosen number.
Step 3 — Distribute Your Macronutrients
With the right calories, distribute macronutrients as follows:
- Protein: 1.8–2.2 g/kg of body weight
- Fat: minimum 0.6 g/kg (essential for hormones)
- Carbohydrates: the remaining calories
Example with 1,500 kcal and 58 kg:
| Macro | Grams | Kcal | |---|---|---| | Protein | 128 g | 512 kcal | | Fat | 46 g | 414 kcal | | Carbohydrates | 144 g | 576 kcal |
Calculate Your Deficit Automatically
Doing these calculations manually is possible, but requires precision and knowledge of the correct parameters.
Nutryon calculates automatically:
- your real TDEE
- the optimal deficit based on your goal
- your personalized macronutrients
- a complete meal plan for the week
Try Nutryon and get your personalized plan in minutes.