How fast can you lose fat?
Faster isn’t better if half of what you lose is muscle. Here’s the pace most evidence and coaches land on.
Short answer
A sustainable rate is about 0.5–1% of bodyweight a week: 0.4–0.8 kg (1–1.8 lb) for someone at 80 kg. Higher body fat allows the faster end; lean people should go slower to protect muscle. Expect it to slow as you get leaner. See your own timeline with the how long to get abs calculator.
Weekly loss by bodyweight
| Bodyweight | 0.5% a week | 1% a week |
|---|---|---|
| 60 kg (132 lb) | 0.30 kg | 0.60 kg |
| 70 kg (154 lb) | 0.35 kg | 0.70 kg |
| 80 kg (176 lb) | 0.40 kg | 0.80 kg |
| 90 kg (198 lb) | 0.45 kg | 0.90 kg |
| 100 kg (220 lb) | 0.50 kg | 1.00 kg |
| 120 kg (265 lb) | 0.60 kg | 1.20 kg |
Why the pace matters
Losing weight faster than about 1% a week for long periods raises the share of lean mass lost, especially if you’re already lean or not lifting. In bodybuilding research, slower cuts preserved more strength and muscle.
Track fat, not water
Day-to-day weight swings by a kilo or more from water and salt. Use a weekly average, a waist measurement every week or two, and matched photos every two to four weeks.
FAQ
Frequently asked questions
Can I lose 1 kg of fat a week?
If you weigh about 100 kg or more, yes. Lighter people should aim lower to protect muscle.
Why did I lose 3 kg in the first week?
Mostly water and glycogen. Fat loss is slower and steadier.
Sources
- Helms ER, Aragon AA, Fitschen PJ (2014). Evidence-based recommendations for natural bodybuilding contest preparation. J Int Soc Sports Nutr 11:20.
- Garthe I et al. (2011). Effect of two different weight-loss rates on body composition and strength in elite athletes. Int J Sport Nutr Exerc Metab 21:97–104.