Evidence receipt
STEP 1: what the trial found
A plain-language summary of one study: who took part, what they got, what it was compared with, what happened in each group, its limits and who paid for it. One trial. Results are group averages, not a prediction for any one person.
Study: STEP 1[1]
Does weekly semaglutide 2.4 mg, with lifestyle support, lead to more weight loss than placebo in adults with obesity or overweight and no diabetes?
- Who was in it
- 1,961 adults with a BMI of 30 or more, or 27 or more with a weight-related condition, without diabetes
- What they got
- Semaglutide 2.4 mg injection once a week, plus lifestyle intervention
- Compared with
- Placebo, plus the same lifestyle intervention
- How long
- 68 weeks
- What happened
- Average body-weight change: −14.9% on semaglutide vs −2.4% on placebo. 4.5% vs 0.8% stopped treatment because of stomach-related side effects.
- Limits
- People with diabetes were excluded
- 68 weeks: no long-term or heart outcomes
- Did not test what happens after stopping
- Funded by
- Novo Nordisk
Summary by Joshua Nichvolodoff, from the published paper — not written by the study's authors. Clinical review: not yet reviewed by a clinician.
Sources
- Once-weekly semaglutide in adults with overweight or obesity (STEP 1). New England Journal of Medicine, March 18, 2021. https://pubmed.ncbi.nlm.nih.gov/33567185/ · DOI 10.1056/NEJMoa2032183 · PMID 33567185. Accessed November 2, 2026. Back to the text
Discussed in: Sevmia, explained · Semaglutide, explained · Wegovy, explained
General information, not medical advice.