Semaglutide weight loss in clinical trials averaged about 15% of body weight over 68 weeks on the 2.4 mg weekly dose (Wegovy), 18.7% on the newer 7.2 mg dose, and 13.6% on the 25 mg daily Wegovy pill.[1][6][7] Most of that loss happens over the first year, and people with type 2 diabetes tend to lose less.[2]
For background on the drug itself, see our semaglutide profile. For how it stacks up against Zepbound and Mounjaro, see semaglutide vs tirzepatide.
Semaglutide weight loss results at a glance
| Trial | Who | Dose | Length | Average weight change | Placebo |
|---|---|---|---|---|---|
| STEP 1 | Adults without diabetes | 2.4 mg weekly | 68 weeks | −14.9% | −2.4%[1] |
| STEP 2 | Adults with type 2 diabetes | 2.4 mg weekly | 68 weeks | −9.6% | −3.4%[2] |
| STEP 3 | With intensive diet and counseling | 2.4 mg weekly | 68 weeks | −16.0% | −5.7%[3] |
| STEP 5 | Adults without diabetes | 2.4 mg weekly | 104 weeks | −15.2% | −2.6%[5] |
| STEP UP | Adults with obesity | 7.2 mg weekly | 72 weeks | −18.7% | −3.9%[6] |
| OASIS 4 | Adults without diabetes | 25 mg pill daily | 64 weeks | −13.6% | −2.2%[7] |
These are averages. Some people lose much more and some lose very little. In STEP 1, half of participants on semaglutide lost at least 15% of their weight, while about 1 in 7 lost less than 5%.[1]
What 15% looks like in pounds
Trials report weight loss as a percentage of starting weight, because a heavier person loses more pounds for the same effect. In STEP 1, the average participant lost 15.3 kg (about 34 lb) on semaglutide versus 2.6 kg (about 6 lb) on placebo.[1] For someone starting at 220 lb, a 15% loss would be about 33 lb; at 300 lb, about 45 lb. These are illustrations, not predictions for any one person.
How much weight do people lose by month?
Month 1
The first four weeks are a starting phase. Wegovy begins at 0.25 mg once a week and rises every four weeks, a schedule meant to reduce nausea, not to produce maximum weight loss.[10] The pill version starts at 1.5 mg daily for 30 days before stepping up.[10] Early weight changes are usually small.
Months 3 to 6
Weight loss picks up as the dose climbs. In a real-world study of 175 patients at a US weight-management clinic, average loss was 5.9% at 3 months and 10.9% at 6 months.[9] In STEP 4, people who completed a 20-week lead-in on semaglutide had already lost an average of 10.6%.[4]
Month 12 and beyond
In STEP 1, weight kept falling for well over a year on the full dose, reaching −14.9% at 68 weeks.[1] STEP 5 showed the loss held at two years: −15.2% at 104 weeks versus −2.6% on placebo.[5]
Who loses more, and who loses less
- Diabetes: people with type 2 diabetes lose less on average. In STEP 2, the 2.4 mg dose gave −9.6% over 68 weeks.[2] In the real-world clinic study, patients with diabetes lost 7.2% at 6 months versus 11.8% for those without.[9]
- Lifestyle support: STEP 3 added a low-calorie diet for 8 weeks and 30 counseling visits. Average loss was 16.0%, the largest in the main STEP program, but the placebo group also lost 5.7%.[3]
- Dose: the 7.2 mg dose, which the Wegovy label now allows for adults who tolerate 2.4 mg for at least 4 weeks and need more weight loss, beat 2.4 mg by about 3 percentage points in STEP UP.[6][10]
Ozempic vs Wegovy vs the pill
All three contain semaglutide. Ozempic is approved for type 2 diabetes and tops out at 2 mg weekly, so its weight effect is usually smaller than Wegovy’s at 2.4 mg or 7.2 mg. Wegovy is the weight-management brand, available as a weekly injection and as a daily tablet.[10] The 25 mg Wegovy pill produced 13.6% weight loss in OASIS 4, close to the injection, though the two were not compared head to head.[7] See our semaglutide dosage chart for each product’s dose steps.
Side effects that affect results
Stomach side effects are the most common reason people slow down or stop.
- STEP 1: nausea and diarrhea were the most common adverse events, usually mild to moderate and easing with time.[1]
- STEP 3: 82.8% on semaglutide had gastrointestinal events versus 63.2% on placebo, and 3.4% stopped because of them.[3]
- OASIS 4: gastrointestinal events affected 74.0% on the pill versus 42.2% on placebo.[7]
- 7.2 mg dose: abnormal skin sensations (dysesthesia) affected 22.9% versus 6.0% on 2.4 mg.[6]
The label also carries a boxed warning about thyroid C-cell tumors seen in rodents.[10] Our guide to semaglutide and cancer risk explains what human studies have found.
What happens when you stop
Weight tends to come back. In STEP 4, people who switched to placebo after 20 weeks regained 6.9% of their body weight over the next 48 weeks, while those who stayed on semaglutide lost another 7.9%.[4]
In the STEP 1 extension, people who stopped semaglutide at 68 weeks had regained about two-thirds of their lost weight a year later. Their net loss fell from 17.3% to 5.6%, and improvements in blood pressure and other heart risk factors faded.[8] For planning around this, see what happens when you stop a GLP-1.
What users report
The bottom line
Expect gradual results: little in the first month, roughly 5% to 10% by six months, and about 15% after a year or more on 2.4 mg, with more on 7.2 mg and somewhat less with type 2 diabetes. Your prescriber sets the dose and how fast to increase it. If the scale stalls, our guide on not losing weight on a GLP-1 covers common reasons.
