How fast can you lose weight safely?
Quick answer
Losing 0.5 to 1 percent of your body weight per week is frequently cited as a practical benchmark.
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Estimate based on general formulas. Individual values may differ.
Weight loss timeline calculator
Estimate based on 1 kg of body fat ≈ 7,700 kcal (Hall et al., 2011).
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Sustainable rate: 0.5–1% of body weight per week (Helms et al., 2014). Aggressive deficits promote muscle loss.
The evidence-based recommendation
In their review of natural dieting, Helms et al. (2014) recommend a weight loss of 0.5 to 1 percent of body weight per week. For someone weighing 80 kg (176 lb), that works out to 400 to 800 grams (0.9–1.8 lb) per week.
Why not faster?
Garthe et al. (2011) compared two rates of loss (0.7% vs. 1.4% per week) in elite athletes. The slower group preserved muscle mass better and even gained strength, while the faster group showed significant muscle loss.
| Body fat percentage | Recommended pace |
|---|---|
| High (> 25%) | 0.8–1% / week |
| Moderate (15–25%) | 0.5–0.8% |
| Low (< 15%) | 0.3–0.5% |
Very rapid weight loss tends to be viewed more critically in the literature than more moderate approaches (Helms et al., 2014).
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- Helms, E. R., et al. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. JISSN, 11:20. jissn.biomedcentral.com
- Garthe, I., et al. (2011). Effect of two different weight-loss rates on body composition and strength. Int J Sport Nutr Exerc Metab, 21(2). PubMed
This content is for general informational purposes only and is not a substitute for medical, nutritional, or therapeutic advice. If you have a medical condition, are pregnant, or take medication, please consult a qualified professional. Recommendations apply to healthy adults.