In STEP 1, the trial behind Wegovy's approval, adults with overweight or obesity and no diabetes lost an average of 14.9% of body weight over 68 weeks on semaglutide 2.4 mg, against 2.4% on placebo (PMID 33567185). In absolute terms that was 15.3 kg from a mean starting weight of 105.3 kg, or about 34 lb from 232 lb.
That single number hides a lot, though. The same dose over the same 68 weeks produced 9.6% in adults who also had type 2 diabetes, and half the STEP 1 participants lost 15% or more while others lost almost nothing. Here is what each Wegovy trial actually measured, and who it measured it in.
- STEP 1 tested semaglutide 2.4 mg, the standard Wegovy dose, in adults with overweight or obesity and no diabetes: average loss was 14.9% of body weight over 68 weeks.
- STEP 2 ran the same dose and duration in adults who also had type 2 diabetes and recorded 9.6%.
- STEP 5 kept the 2.4 mg dose going for 104 weeks and recorded 15.2%, so the bulk of the loss lands in the first year.
- Wegovy HD, the 7.2 mg dose approved in the United States in March 2026, averaged 18.7% over 72 weeks in the STEP UP trial.
What Wegovy is, and why the dose is the whole story
Wegovy is semaglutide, the same molecule as Ozempic, licensed for chronic weight management rather than for type 2 diabetes. The difference that matters for any weight loss figure is the ceiling. Ozempic's maximum labelled dose is 2 mg. Wegovy's standard maintenance dose is 2.4 mg, and since March 2026 a higher-dose version sold as Wegovy HD is licensed in the United States at 7.2 mg for adults who have already tolerated 2.4 mg for at least four weeks.
This is why percentages move around so much online. Nearly every widely circulated semaglutide result, the 14.9% figure included, comes from a trial of 2.4 mg, which is a Wegovy dose and not one Ozempic can reach. We covered what Ozempic's own 2 mg trials measured separately, and the gap between the two is real rather than a rounding difference.
The label also builds up to 2.4 mg in four-week steps, starting at 0.25 mg and passing through 0.5 mg, 1 mg and 1.7 mg before the maintenance dose from week 17. That escalation is the main reason a real-world weight curve looks flatter in its first four months than a headline trial average suggests.
How much weight can you lose on Wegovy?
Every figure below names its trial, its dose, whether the participants had type 2 diabetes, and how long it ran. Any percentage missing one of those four is not comparable to the others.
| Trial | Dose | Population | Duration | Mean weight change |
|---|---|---|---|---|
| STEP 1 (PMID 33567185) | Semaglutide 2.4 mg | Overweight or obesity, no diabetes | 68 weeks | -14.9% (placebo -2.4%) |
| STEP 2 (PMID 33667417) | Semaglutide 2.4 mg | Overweight or obesity with type 2 diabetes | 68 weeks | -9.6% (placebo -3.4%) |
| STEP 5 (PMID 36216945) | Semaglutide 2.4 mg | Overweight or obesity, no diabetes | 104 weeks | -15.2% (placebo -2.6%) |
| STEP UP (PMID 40961952) | Semaglutide 7.2 mg | Obesity, no diabetes | 72 weeks | -18.7% (2.4 mg arm -15.6%, placebo -3.9%) |
Without type 2 diabetes: 14.9% over 68 weeks
STEP 1 randomly assigned 1961 adults with a BMI of 30 or above, or 27 and above with a weight-related condition, to semaglutide 2.4 mg or placebo for 68 weeks, with a lifestyle intervention in both arms. Mean change in body weight was -15.3 kg on semaglutide against -2.6 kg on placebo.
The distribution is more useful than the average. At week 68, 86.4% of the semaglutide group had lost at least 5% of their starting weight, 69.1% had lost at least 10%, and 50.5% had lost at least 15%. In the placebo group the same thresholds were reached by 31.5%, 12.0% and 4.9%.
With type 2 diabetes: 9.6% over 68 weeks
STEP 2 ran the same dose for the same 68 weeks in adults with overweight or obesity and type 2 diabetes, with an HbA1c between 7% and 10%. It compared semaglutide 2.4 mg, semaglutide 1.0 mg and placebo. Mean weight change was -9.6%, -7.0% and -3.4% respectively.
So the same drug at the same dose for the same length of time produced about a third less weight loss when the participants had type 2 diabetes. Real-world data points the same way: in a retrospective study of 175 patients on semaglutide for weight loss, six-month loss averaged 11.8% for people without type 2 diabetes and 7.2% for people with it.
What the first six months look like
The trials above report their endpoint, not a monthly curve, so a month-by-month picture has to be assembled from separate sources. Each row here is labelled with where it comes from.
| Point in treatment | Average loss | Where it comes from |
|---|---|---|
| 3 months | 5.9% | Real-world cohort, 175 patients on semaglutide for weight loss (6.3% without type 2 diabetes, 3.9% with it) |
| Week 20, about 4.5 months | 10.6% | STEP 4 run-in: 803 adults without diabetes who completed the 16-week escalation and four weeks at 2.4 mg |
| 6 months | 10.9% | Same real-world cohort (11.8% without type 2 diabetes, 7.2% with it) |
| Week 68, about 15.5 months | 14.9% | STEP 1, semaglutide 2.4 mg, no diabetes |
| Week 104, two years | 15.2% | STEP 5, semaglutide 2.4 mg, no diabetes |
Two caveats on that table. The real-world cohort was prescribed semaglutide at a range of doses rather than 2.4 mg across the board, so its figures are a floor rather than a like-for-like version of STEP 1. And the STEP 4 run-in was not a randomised comparison, it is simply what the participants who reached the maintenance dose weighed at week 20 before the trial's randomisation began.
Year two adds much less than year one
STEP 5 followed 304 adults with overweight or obesity and no diabetes on semaglutide 2.4 mg or placebo for 104 weeks. Mean weight change at two years was -15.2% against -2.6% on placebo, and 77.1% of the semaglutide group were at least 5% below their starting weight at week 104.
STEP 1 and STEP 5 are separate trials, so the difference between 14.9% at 68 weeks and 15.2% at 104 weeks is not a clean measure of what the second year adds. What both curves show is the same shape: fast loss while the dose escalates, a slower stretch through the rest of the first year, then a long flat run once the body has adjusted to the maintenance dose.
What the data shows about stopping
STEP 1 had an extension that followed 327 participants for 52 weeks after treatment and lifestyle support ended. In that subset, mean weight loss to week 68 was 17.3% on semaglutide. By week 120, a year after stopping, they had regained 11.6 percentage points, leaving a net 5.6% below their starting weight. Improvements in blood pressure, lipids and glycaemic markers largely moved back toward baseline over the same year.
That is roughly two thirds of the loss coming back within a year of stopping, which is why prescribers generally treat semaglutide as ongoing treatment rather than a fixed course.
The 7.2 mg dose raises the ceiling
STEP UP, a phase 3b trial published in 2025, randomly assigned 1407 adults with a BMI of 30 or above and no type 2 diabetes to semaglutide 7.2 mg, semaglutide 2.4 mg or placebo for 72 weeks. Mean baseline weight was 113 kg and mean BMI 39.9.
Average weight change was -18.7% on 7.2 mg, -15.6% on 2.4 mg and -3.9% on placebo. Among participants who stayed on treatment throughout, the figures were -20.7% and -17.5%. About a third of the 7.2 mg group lost 25% or more of their body weight, against 16.7% on 2.4 mg. Altered skin sensation, reported as dysesthesia, came up in 22% of the 7.2 mg group compared with 6% on 2.4 mg and 0.3% on placebo. The United States approval in March 2026 covers adults who have already tolerated 2.4 mg for at least four weeks.
Why individual results vary this much
Half of the STEP 1 semaglutide group lost 15% or more and roughly one in seven did not reach 5%, on the same dose for the same 68 weeks. The factors behind that spread are well documented:
- Type 2 diabetes status. The single largest split in the data, worth several percentage points at every time point measured.
- Dose actually reached. Trial averages assume participants reached and stayed on the maintenance dose. People who stop at a lower step because of side effects sit lower on the curve.
- Time on treatment. The curve is front-loaded, so someone four months in and someone 14 months in are not comparable.
- Starting weight. Percentages translate into very different pound counts, and the same percentage from 300 lb and 180 lb are different experiences.
- What the lifestyle intervention looked like. Every STEP trial paired the drug with structured diet and activity counselling in both arms, including placebo.
Put your own numbers against the trial curve
See what STEP 1's percentages work out to in pounds from your starting weight, week by week.
A percentage is easy to quote and hard to picture. Running your starting weight through a GLP-1 weight loss calculator turns 14.9% into an actual pound figure and a week-by-week shape, which is a more honest reference point than a single population average. If you want to see how different tools handle this, we compared the main online weight loss calculators and what data each one is built on.
FAQ
How much weight can you lose on Wegovy in a year?
The closest trial figure is STEP 1, which recorded an average loss of 14.9% of body weight over 68 weeks on semaglutide 2.4 mg in adults without diabetes. STEP 5 ran the same dose for 104 weeks and recorded 15.2%, so most of the loss in those trials happened inside the first year.
Is Wegovy the same as Ozempic?
Both contain semaglutide, but the licensed doses differ. Ozempic is licensed for type 2 diabetes with a 2 mg maximum, while Wegovy is licensed for chronic weight management at a 2.4 mg maintenance dose, with a 7.2 mg version approved in March 2026. Almost every widely quoted semaglutide weight loss percentage comes from a 2.4 mg trial, which is a Wegovy dose.
How much weight can you lose on Wegovy with type 2 diabetes?
In STEP 2, adults with overweight or obesity and type 2 diabetes lost an average of 9.6% of body weight over 68 weeks on semaglutide 2.4 mg, against 3.4% on placebo. That is roughly a third less than STEP 1 recorded at the identical dose and duration in people without diabetes.
How fast does Wegovy work?
A real-world study of 175 patients taking semaglutide for weight loss found an average loss of 5.9% at three months and 10.9% at six months. In STEP 4, the 803 participants who completed a 20-week dose escalation and reached 2.4 mg had lost an average of 10.6% by that point.
Do you regain the weight after stopping Wegovy?
In the STEP 1 trial extension, 327 participants were followed for 52 weeks after treatment ended. Those who had been on semaglutide lost an average of 17.3% to week 68, then regained 11.6 percentage points by week 120, leaving them 5.6% below their starting weight. Most of the cardiometabolic improvements moved back toward baseline as well.
How much more does the 7.2 mg dose achieve?
In STEP UP, 1407 adults with obesity and no diabetes were randomly assigned to semaglutide 7.2 mg, 2.4 mg or placebo for 72 weeks. Average loss was 18.7% on 7.2 mg, 15.6% on 2.4 mg and 3.9% on placebo. Altered skin sensation was reported by 22% of the 7.2 mg group against 6% on 2.4 mg.
Sources
- Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021;384(11):989-1002. PMID: 33567185
- Davies M, Féderèr Hansen K, Lingvay I, et al. Semaglutide 2·4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial. Lancet. 2021;397(10278):971-984. PMID: 33667417
- Rubino D, Abrahamsson N, Davies M, et al. Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial. JAMA. 2021;325(14):1414-1425. PMID: 33755728
- Garvey WT, Batterham RL, Bhatta M, et al. Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial. Nat Med. 2022;28(10):2083-2091. PMID: 36216945
- Wilding JPH, Batterham RL, Davies M, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553-1564. PMID: 35441470
- Wharton S, Davies M, Lingvay I, et al. Once-weekly semaglutide 7·2 mg in adults with obesity (STEP UP): a randomised, controlled, phase 3b trial. Lancet Diabetes Endocrinol. 2025. PMID: 40961952
- Ghusn W, De la Rosa A, Sacoto D, et al. Weight Loss Outcomes Associated With Semaglutide Treatment for Patients With Overweight or Obesity. JAMA Netw Open. 2022;5(9):e2231982. PMID: 36121652
This article is for information only and is not medical advice. Dosing, suitability and any change to treatment are decisions for your prescriber.