How much weight do people lose on Wegovy (semaglutide 2.4 mg) by week 12?

In the STEP 1 trial the average participant had lost about 6% of starting body weight by week 12 and 14.9% by week 68.

How much weight do people lose on Zepbound (tirzepatide)?

In SURMOUNT-1 the average loss at 72 weeks was 15.0% on 5 mg, 19.5% on 10 mg and 20.9% on 15 mg.

How much protein should I eat on a GLP-1 medication?

Most clinicians suggest 1.2 to 1.6 grams of protein per kilogram of body weight per day while losing weight on a GLP-1, to limit lean-mass loss.

Where should you be on the GLP-1 curve?

Enter your weight and medication. You get the average weight-loss curve from the phase 3 trials (STEP 1, SURMOUNT-1, OASIS 4, SCALE), the range most people fall in, your milestones at 12, 24, 52 weeks, and a daily protein target to protect muscle.

Units

Starting weight (lb) Height (in) Medication

Dose = the maintenance dose you are titrating toward. Trials reached it by week 16–20.

Already on it? Plot where you are

Current weight (lb) Weeks since first dose

Trial average Typical range Placebo + lifestyle (STEP 1)

Protein target while you lose

Roughly a quarter to a third of weight lost on a GLP-1 can be lean mass if protein and resistance training are low. The common clinical target while losing is 1.2–1.6 g of protein per kg of body weight per day. Your number, based on the weight above:

If your BMI is above 35, many clinicians calculate from adjusted body weight instead — that lands near the lower end of your range. Spread protein across 3–4 meals; appetite on a GLP-1 makes one big protein meal hard.

Not on a GLP-1 yet, or paying too much?

These are licensed US telehealth platforms that prescribe brand-name GLP-1s (Wegovy, Zepbound, Ozempic). We link only to brand-name programs, not compounded products.

Ro

Brand-name Wegovy and Zepbound, insurance navigation, video visits. Widest medication menu.

Check eligibility

Hims / Hers

Fully online, brand-name Wegovy and Ozempic after the 2026 Novo Nordisk partnership. Simplest flow.

See pricing

Found

Obesity-medicine physicians, coaching, and non-GLP-1 options if you don't qualify.

See plans

Direct from the manufacturer

Self-pay vials: Zepbound via LillyDirect, Wegovy via NovoCare. Needs your own prescription.

LillyDirect

What people on a GLP-1 actually end up buying

Unflavored whey isolateHits the protein number when you can't face a full meal Food scale in gramsProtein targets only work if you weigh the chicken Pen travel coolerPens need to stay below 86°F once in use Body-composition scaleWeekly weigh-ins are what the curve above is built on

Links to Ro, Hims, Found and Amazon are affiliate links. We may earn a commission; it does not change what you pay.

Go deeper

Compare the drugsOverlay all six curves, dosing, who each suits Side effects by weekRates, what helps, red flags Keeping it offRegain data and a maintenance calculator

Questions people ask at week 4, 12 and 40

I'm at week 8 and only down 3%. Am I a non-responder?

Not yet. Trial doses were still being stepped up at week 8; the average curve is only about 4% down there. Clinicians usually judge response at the maintenance dose, around week 16–20. In STEP 1, 86% of people on semaglutide lost at least 5% by the end.

Why has the curve gone flat around week 40?

Because it does for almost everyone. Trial averages plateau between weeks 40 and 60. The flat part is maintenance, not failure. A second plateau is not a reason to raise the dose by yourself — that is a conversation with your prescriber.

Is tirzepatide really better than semaglutide?

Head-to-head, SURMOUNT-5 (2025) found tirzepatide 20.2% vs semaglutide 13.7% at 72 weeks. The gap is real on average; individuals vary a lot, and cost and availability often decide.

Does the pill work as well as the shot?

Oral semaglutide 25 mg lost about 13.6% at 64 weeks in OASIS 4, versus 14.9% for the 2.4 mg injection at 68 weeks — close, slightly less.

Where do these numbers come from?

Published phase 3 trial means: STEP 1 (Wilding et al., NEJM 2021), SURMOUNT-1 (Jastreboff et al., NEJM 2022), OASIS 4 (Wharton et al., NEJM 2025), SCALE (Pi-Sunyer et al., NEJM 2015), SURMOUNT-5 (Aronne et al., NEJM 2025). The curve between published timepoints is interpolated. The full table is at /trials.json and on the methods page.

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