Verbatim response from Perplexity
Most people lose weight on GLP-1s gradually, not all at once: a common real-world pace is about 1–2 lb per week, with larger losses over time as the dose is titrated and appetite remains lower.[1][7] In clinical studies, average weight loss is often around 10%–15% of body weight over about 1 year, and some of the most effective options reach 15%–25% in certain trials or populations.[3][4][5][6]
Whether it is sustainable depends on whether you stay on treatment and keep up the lifestyle changes that support it. Trials and reviews show weight loss can be maintained while the medication is continued, including semaglutide over 104 weeks and tirzepatide in longer follow-up, but stopping the drug often leads to weight regain.[1][4] Harvard also notes that some reports raise concern for muscle loss during rapid weight loss, which makes adequate protein, resistance training, and monitoring important.[3]
What to expect in practice:
- First month: some people lose 5–10 lb, mostly from lower intake and reduced appetite.[1]
- By 3 months: a typical healthy range is about 5%–10% of body weight for many patients, though results vary widely.[1]
- By 6–12 months: many people are in the 10%–20% range, depending on the medication and adherence.[1][3][4][5][6]
The pace is usually considered reasonable if it is roughly up to 2 lb/week on average, but faster loss can be okay in some cases if a clinician is monitoring for dehydration, gallbladder issues, excessive calorie restriction, or muscle loss.[1][7]
If you want, I can also give you a month-by-month expectation for semaglutide vs tirzepatide, or help estimate your likely weight loss based on your starting weight.