"How fast?" hides two questions: how much weight per week, and how many calories under maintenance that takes. A bigger deficit is always possible. The useful question is what it costs you, in muscle, energy and how long you can keep it up.
The short version
- A common range is about 0.5 to 1% of body weight a week, or 1 to 2 pounds, whichever is smaller for you.
- The 3,500-calories-per-pound rule turns that into a daily gap of roughly 300 to 1,000 calories, depending on how much you weigh.
- Slower is gentler on muscle, and the CDC says steady loss is more likely to stay off. Faster is not forbidden, but it costs more.
Two ways to say the same pace
The CDC describes a gradual, steady pace of about 1 to 2 pounds a week as more likely to keep the weight off than faster loss. Researchers who study lifters use a share of body weight instead: about 0.5 to 1% a week to keep the most muscle (Helms and colleagues, 2014). The two agree near 200 pounds, where 1% is 2 pounds. A 300-pound person's 1% is 3 pounds, above the CDC range, and a 130-pound person's 1% is only 1.3. So the smaller of the two numbers is a sensible cap, and it is what the goal date calculator warns on.
To turn weight into calories, use the usual rule of thumb: a pound is about 3,500 calories, so 1 pound a week is about 500 a day. Here is what four paces mean for three body weights. Each cell shows the kilograms lost a week and the calories a day below maintenance:
| Pace a week | 60 kg (132 lb) | 80 kg (176 lb) | 100 kg (220 lb) |
|---|---|---|---|
| 0.25% | 0.15 kg 170 kcal | 0.20 kg 220 kcal | 0.25 kg 280 kcal |
| 0.5% | 0.30 kg 330 kcal | 0.40 kg 440 kcal | 0.50 kg 550 kcal |
| 0.75% | 0.45 kg 500 kcal | 0.60 kg 660 kcal | 0.75 kg 830 kcal |
| 1% | 0.60 kg 660 kcal | 0.80 kg 880 kcal | 1.00 kg 1,100 kcal |
What the studies found
- Athletes who lift. In a trial of 24 athletes doing four lifting sessions a week, a group aiming for 0.7% of body weight a week lost fat and gained 2.1% in lean mass. A group aiming for 1.4% lost about the same body weight but kept lean mass flat. The slow group cut intake by 19%, the fast group by 30% (Garthe and colleagues, 2011).
- Deficit size. A meta-analysis found lean mass gains were impaired in people lifting in an energy deficit compared with those who were not. Its meta-regression put the size at about 500 calories a day, enough to stop lean mass gains, and the authors advise people trying to keep muscle during weight loss to avoid deficits above that (Murphy and Koehler, 2022).
A worked example
An 80 kg person who wants to lose 10 kg picks 0.5% a week.
- Weekly loss: 80 x 0.005 = 0.4 kg, about 0.88 pounds.
- Daily gap: 0.88 x 3,500 / 7 = about 440 calories below maintenance. The deficit table above gives the same figure.
- Time: 10 / 0.4 = 25 weeks. At 1% a week it would be 12.5 weeks and a gap near 880 calories, above the 500 the meta-regression flagged for keeping lean mass.
Picking yours
Start in the gradual to moderate part of the range, 0.25 to 0.5% of body weight a week, and see how training, sleep and hunger go for a few weeks. Move faster only for a reason, such as a short deadline, and take muscle and energy into account. If you are under 18, have a medical condition or a history of disordered eating, talk to a doctor or dietitian before choosing a pace at all. Vital's three goal paces are 0.25, 0.5 and 0.75% of body weight a week, and the Progress screen compares your actual pace with the one you set.
What we are less sure about
- The athlete trial is small and short. It had 24 people over about 5 to 9 weeks. The fast group's measured loss was nearer 1.0% a week than the 1.4% it aimed for, so it is not a clean 0.7 against 1.4 comparison. The gap in how much each group cut its intake is real.
- The 3,500 rule is rough. It is only about right for people with a lot of body fat. For leaner people it overstates the deficit needed per pound lost, because lean tissue holds less energy than fat (Hall, 2008).
- Weight loss slows. Body weight responds slowly to a change in intake, with half times of about a year (Hall and colleagues, 2011). A straight-line plan is a best case, and early loss includes water.
- Who the ranges fit. The 0.5 to 1% range was written for lean lifters preparing for competition. The CDC range is guidance rather than a test of one pace against another. Neither tells you the best pace for your body and life.
- Speed is not the only thing. Protein and lifting also affect how much muscle you keep, and these studies cannot separate them cleanly.
Sources
- Centers for Disease Control and Prevention. Steps for Losing Weight. Healthy Weight and Growth. cdc.gov
- Garthe I, Raastad T, Refsnes PE, Koivisto A, Sundgot-Borgen J. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab 2011;21(2):97-104. doi:10.1123/ijsnem.21.2.97
- Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr 2014;11:20. doi:10.1186/1550-2783-11-20
- Murphy C, Koehler K. Energy deficiency impairs resistance training gains in lean mass but not strength: a meta-analysis and meta-regression. Scand J Med Sci Sports 2022;32(1):125-137. doi:10.1111/sms.14075
- Hall KD. What is the required energy deficit per unit weight loss? Int J Obes 2008;32(3):573-576. doi:10.1038/sj.ijo.0803720
- Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet 2011;378(9793):826-837. doi:10.1016/S0140-6736(11)60812-X
Written November 5, 2026. This is general information, not medical advice. Talk to a doctor or dietitian before big changes to how you eat or train, especially with a medical condition or a history of disordered eating.