Semaglutide Results: What the STEP 1 Trial Showed (-14.9%)
STEP 1 is the landmark trial behind semaglutide for weight loss. Here is what it actually measured, in plain language, with honest context.
The headline number
In the STEP 1 trial (Wilding et al., New England Journal of Medicine, 2021; PMID 33567185), adults with overweight or obesity who took semaglutide 2.4 mg once weekly lost an average of 14.9% of their body weight over 68 weeks, compared with 2.4% on placebo. For a 220 pound starting weight, 14.9% is roughly 33 pounds. These are averages, and individual results vary and are not guaranteed.
How many people hit major milestones?
STEP 1 did not just move the average. A large share of participants reached meaningful thresholds: most lost at least 5% of body weight, a majority reached 10% or more, and roughly a third lost 20% or more, the kind of result once associated mainly with surgery. The point is that the average hides a range, and reaching an effective dose with support pushes you toward the upper end.
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One month of medical-grade compounded semaglutide, the $119 doctor review, and a free B-12/lipotropic injection. No long-term commitment.
Start the 30-day trialWere there side effects?
Yes, mostly gastrointestinal: nausea, diarrhea, constipation, and vomiting were the most common, generally mild to moderate and most frequent during dose escalation. A measured titration and physician follow-up are how those are kept manageable, which is one reason supervised care matters.
How does this compare to tirzepatide?
Semaglutide acts on one appetite pathway (GLP-1). Tirzepatide acts on two (GLP-1 and GIP) and produced a higher average loss in its own trial (about 20.9% at the top dose in SURMOUNT-1). The right medication for you is a medical decision based on your health, tolerance, and goals, not just the headline average.
Frequently asked questions
How much weight did people lose on semaglutide in STEP 1?
An average of 14.9% of body weight over 68 weeks on semaglutide 2.4 mg, versus 2.4% on placebo (Wilding et al., NEJM 2021, PMID 33567185). For a 220 pound person that is about 33 pounds on average. Many lost more and some less; reaching an effective dose and staying consistent push you toward the upper end. Results vary and are not guaranteed.
How long did it take to reach that result?
STEP 1 measured weight at 68 weeks (about 16 months), with the dose titrated up gradually over the first months. Most people feel reduced appetite within the first weeks, and weight comes off steadily as the dose increases. A deliberate, sustainable pace protects muscle and is less likely to rebound than a rapid drop.
Is compounded semaglutide the same as what STEP 1 studied?
No. STEP 1 studied the brand-name product. Compounded semaglutide is prepared by licensed U.S. pharmacies and is not an FDA-approved or brand-identical medication. The trial informs us about the active ingredient and dose; it is not a study of any specific compounded preparation. A physician confirms whether it is appropriate for you.
Will I keep the weight off after the trial period?
Keeping weight off is a separate phase. When the medication is stopped abruptly with no plan, some regain is common because appetite returns. A maintenance dose or a gradual, supervised taper, plus the nutrition and activity habits built along the way, make lasting results realistic. We plan for maintenance from the start.
How do I start semaglutide safely?
Through a physician who screens your health history and contraindications, sets the starting dose, and titrates it up with follow-up. Take our 2-minute quiz or call to begin. Starting low and increasing slowly is how side effects are kept manageable and how more people stay on long enough to see results.
This article is informational only and not medical advice. Speak with a licensed physician before starting or changing any GLP-1 therapy. Individual results vary. New Hope Weight Loss is a physician-supervised medical weight loss clinic in Costa Mesa, CA. Eligibility for treatment is determined during the medical consultation. Compounded semaglutide and compounded tirzepatide are not the same products as Wegovy®, Ozempic®, Mounjaro®, or Zepbound®.