How Big Should Your Calorie Deficit Be? 300 vs 500 vs 1000 Cal Compared
300-Calorie Deficit: The Slow Cut
Expected loss: ~0.25–0.3 kg/week. Easiest to maintain, lowest hunger, minimal muscle loss risk, minimal metabolic adaptation. Best for: athletes who want to maintain performance while cutting; people maintaining fat loss after a bigger cut; those who find larger deficits unsustainable.
500-Calorie Deficit: The Sweet Spot
Expected loss: ~0.4–0.5 kg/week. The most evidence-supported approach for general fat loss. Provides meaningful progress (2 kg/month) while being sustainable with reasonable hunger. Can be maintained for several months. Combine with high protein and resistance training.
1000-Calorie Deficit: Aggressive Cut
Expected loss: ~0.7–0.8 kg/week (initially). Significantly more muscle loss, stronger metabolic adaptation, and harder to sustain. Research shows that after 4–6 weeks at 1000-calorie deficit, metabolic adaptation reduces actual loss to near 500-calorie deficit levels anyway — so the early ‘extra loss’ is largely water and glycogen.
Choosing Based on Your Situation
Use Calorie Deficit Calculator to see what each deficit size means in terms of weeks to goal. If you have 3+ months, a 500-calorie deficit is almost always optimal. If you have a specific deadline (wedding, event) in under 6 weeks, a 700–750 deficit with high protein and training is a reasonable short-term approach.
Frequently Asked Questions
Calculate your ideal deficit
Open Calorie Deficit Calculator to find the right deficit size for your goal and timeline.
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