How much weight will I lose on a GLP-1?

The cleanest data, all in adults without diabetes, lifestyle counseling included: | Drug | Trial | Duration | Average loss | ≥20% losers | | --- | --- | --- | --- | --- | | Tirzepatide 15 mg | SURMOUNT-1 | 72 wks | 20.9% | ≈57% | | Tirzepatide 5 mg | SURMOUNT-1 | 72 wks | 16.0% | ≈30% | | Semaglutide 2.4 mg | STEP 1 | 68 wks | 14.9% | ≈32% | | Liraglutide 3 mg | SCALE | 56 wks | ≈8% | rare | (People with type 2 diabetes consistently lose a few points less — roughly 10–12% on semaglutide, ≈15% on tirzepatide.) Reading the spread honestly: averages mislead in both directions. In STEP 1, about a third of semaglutide patients lost 20%+ (bariatric-surgery territory) while roughly one in seven lost under 5%. Strong early response (≥5% by month 3–4 at meaningful doses) predicts strong final results; minimal response by then predicts staying modest and is a reason to reassess the plan, not to grind for a year. What moves your personal number: reaching (or not needing) higher maintenance doses, staying on long enough — the loss phase runs 12–18 months, not 12 weeks — protein and resistance training to keep the loss fat-weighted, and not letting liquid calories sneak around the appetite suppression. Compounded and sublingual forms borrow these numbers less reliably; injections are where the data lives.