What is a calorie?
A calorie is a unit of energy. The food you eat contains calories (energy in). Your body burns calories to stay alive, move and exercise (energy out). This is basic thermodynamics — energy can't be created or destroyed, only converted.
What is a calorie deficit?
A calorie deficit means you're consuming fewer calories than your body burns. When this happens, your body uses stored energy (body fat) to make up the difference. That's how weight loss works — there's no way around this fundamental principle.
Calories in < calories out = weight loss
Calories in > calories out = weight gain
Calories in = calories out = weight maintenance
Track both sides of the equation with Trakon.
AI food scanning for calories in + GPS activity tracking for calories out.
How big should your deficit be?
A safe and sustainable calorie deficit is 300-500 calories per day. This leads to roughly 0.3-0.5 kg (0.5-1 lb) of weight loss per week — a pace that's maintainable and minimizes muscle loss.
| Deficit/day | Weekly deficit | Expected loss/week | Sustainability |
|---|---|---|---|
| 300 cal | 2,100 cal | ~0.3 kg | Very sustainable |
| 500 cal | 3,500 cal | ~0.5 kg | Sustainable |
| 700+ cal | 4,900+ cal | ~0.6+ kg | Hard to sustain, risk of muscle loss |
Larger deficits can work short-term but often lead to bingeing, fatigue and giving up. Slow and steady wins.
How to calculate your daily calorie needs
Your total daily energy expenditure (TDEE) is made up of:
- BMR (Basal Metabolic Rate) — calories burned at rest (~60-70% of TDEE)
- NEAT — daily movement (walking around, standing, fidgeting)
- Exercise — planned workouts
- TEF (Thermic Effect of Food) — calories burned digesting food (~10%)
You can estimate your TDEE using online calculators (search "TDEE calculator"). Then subtract 300-500 calories to get your daily target for weight loss.
Track calories in and out — automatically.
Trakon estimates calories burned from GPS activities and calories consumed from AI food scanning.
How to create a deficit
You have two levers: eat less (reduce calories in) or move more (increase calories out). The best approach uses both:
- Eat 200 fewer calories — skip a snack, reduce portions, swap soda for water
- Burn 200 more calories — 30-minute brisk walk or 20-minute jog
- Total deficit: 400 calories/day — sustainable and healthy
Common mistakes
- Too large a deficit — leads to hunger, fatigue and giving up
- Not tracking accurately — underestimating portions is the #1 reason people fail
- Forgetting liquid calories — a latte can have 300+ calories
- Comparing daily weight — track weekly averages, not daily fluctuations
- Not eating enough protein — protein preserves muscle during a deficit
Is a calorie deficit safe?
For most healthy adults, a moderate deficit of 300-500 calories is safe and effective. However, if you have any medical conditions, are pregnant, or have a history of eating disorders, consult a healthcare professional before starting any calorie-restricted diet. This article is educational and not a substitute for medical advice.
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Read next: How to Track Calories for Weight Loss or Weight Loss FAQ