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What changes did people notice first?
Eating changes were an early part of the reported experience. In a selected phase 2 interview sample, 31 of 36 retatrutide-treated participants recalled a change within eight weeks, including smaller portions, less frequent hunger and easier fullness.3
The first weeks also included dose escalation. TRIUMPH-1 began at 2 mg once weekly, with four-week increases toward the assigned target; its 12 mg group reached that target after the earlier 2, 4, 6 and 9 mg stages.9
That puts a first-month result in context: participants were still at an early dose. The later averages below reflect sustained treatment, rather than a predictable number of kilograms in each week.
See the weekly dosage and titration guide for the complete trial schedule.
Did the appetite changes continue beyond the first few weeks?
Questionnaires in the phase 2 obesity trial found lower perceived hunger and less tendency to overeat with retatrutide than placebo at both 24 and 48 weeks. This was an exploratory secondary analysis using an eating-behavior questionnaire.4
Researchers assessed hunger separately from disinhibition: losing control of eating in response to cues, mood changes or disruptions. Scores improved on both measures. The study did not collect food diaries that would establish an exact daily calorie reduction.4
For someone asking about “food noise,” these are the concrete findings: less perceived hunger and less cue-driven overeating. They help explain interest in portion control over time, without assigning everyone a day on which cravings will disappear.
What were the results at roughly six months and one year?
The 2023 phase 2 trial enrolled 338 adults with obesity, or overweight plus a related health condition. These are the published mean results for its 12 mg target group, using the study’s least-squares estimates.1
| Time point | Retatrutide 12 mg group | Placebo |
|---|---|---|
| 24 weeks | 17.5% weight reduction | 1.6% |
| 48 weeks | 24.2% weight reduction | 2.1% |
Published phase 2 group averages.1
The paper describes continued weight loss through week 48, with the group curves not yet showing a plateau.1
Six months and one year are approximate everyday labels; the actual measurements were at 24 and 48 weeks. The increase between those visits describes this trial’s experience. It does not establish a constant monthly rate or a schedule for increasing a personal dose.
How much weight changed in the larger phase 3 study?
TRIUMPH-1 randomized 2,339 adults with obesity, without diabetes. Its published 80-week results used a treatment-regimen analysis that accounts for treatment discontinuation.2
| Assigned group | Mean reduction from starting weight |
|---|---|
| 4 mg target | 17.6% |
| 9 mg target | 23.7% |
| 12 mg target | 25.0% |
| Placebo | 3.9% |
Treatment-regimen / intention-to-treat estimates.2
This is a separate trial from the 48-week study above. Putting the two tables together does not create one continuous patient journey. Differences in the study population and analysis also matter when comparing their endpoints.
“Target” identifies the group’s assigned dose after escalation. It is not the starting amount, and the table does not select a dose for an individual.
Compare retatrutide vials and the preloaded pen
10 mg vial · 30 mg vial · 15 mg / 3 mL autoinjector. Check each format’s total quantity and the original vial certificates.
What would 10%, 15%, 20% or 25% mean in kilograms or pounds?
Convert a percentage using starting weight × percentage ÷ 100. The result is the amount reduced; subtract it from starting weight to obtain the arithmetic remaining weight.
| Starting weight | 10% | 15% | 20% | 25% |
|---|---|---|---|---|
| 80 kg | 8 kg | 12 kg | 16 kg | 20 kg |
| 100 kg | 10 kg | 15 kg | 20 kg | 25 kg |
| 120 kg | 12 kg | 18 kg | 24 kg | 30 kg |
For example, a 15% reduction from 100 kg means 15 kg reduced and 85 kg remaining. The same formula works in pounds: 15% of 200 lb is 30 lb, leaving 170 lb.
What does a percentage change mean in kg or lb?
Enter any starting weight and percentage to translate a relative change into a weight amount. This is arithmetic, not a prediction of retatrutide results.
10% of 100 kg is 10 kg. Subtracting that amount gives 90 kg.
The unit labels the weight you enter; changing it does not convert the number. Values are rounded to two decimal places. Calculations stay in your browser.
The calculator labels the weight you enter as kg or lb. It performs percentage arithmetic; it does not automatically convert units, predict a retatrutide result or recommend a target weight.
Why can two people lose different amounts at the same percentage?
The starting weight sets the absolute amount. In the table, 20% corresponds to 16 kg from 80 kg and 24 kg from 120 kg. Conversely, the same number of kilograms can represent different percentages of two starting weights.
How much did waist size change?
In TRIUMPH-1’s efficacy analysis, the 12 mg group averaged a 24.1 cm waist reduction at 80 weeks, compared with 3.6 cm with placebo. This analysis estimates the effect under continued trial treatment and differs from the weight analysis in the table above.5
Waist change gives a direct body-size result alongside the scale. It is useful when the before-and-after question is about the abdomen or how clothes fit. It cannot specify where every kilogram of fat came from or translate automatically into a certain clothing size.
The scale measures total body weight; a waist measurement describes circumference. Keep those units separate: a centimetre reduction, a percentage of body weight and a percentage of fat mass are different outcomes. The benefits and body-composition guide explains the evidence for each.
Was the change on the scale actually body fat?
A separate 36-week DXA substudy in people with type 2 diabetes measured a 23.2% reduction in total fat mass in the 12 mg retatrutide group, versus 4.5% with placebo. The analysis used on-treatment scan data. Lean tissue also decreased.6
This supports a real body-fat component to the change. It also explains why total weight loss should not be described as pure fat loss. The study population and measurement were different from the main obesity trials above.
A fat-mass percentage uses the starting amount of fat as its denominator. As an arithmetic example, a 20% reduction from 30 kg of fat mass means 6 kg less fat. It does not mean total body weight fell 20%, or that body-fat percentage fell by 20 percentage points.
What did participants say about meals, energy and movement?
Published phase 2 interviews describe changes beyond the scale. These are paraphrased research accounts, rather than product testimonials:
- Meals: one participant described feeling full earlier and rarely returning for second helpings.
- Activity: another linked weight loss with being able to walk and hike on holiday.
Among the 36 retatrutide-treated interviewees, 27 reported better mobility, 24 better energy and 24 smaller clothing sizes. Experiences were not uniformly positive; some reported adverse effects or unmet weight goals.3
These reports describe a selected interview sample. They add the person’s experience of a change, while the randomized trials answer the separate question of average treatment effect.
Were the results the same in people with type 2 diabetes?
A separate trial produced a different average. TRIUMPH-2 randomized 1,152 adults with type 2 diabetes and BMI of at least 27. At 80 weeks, the 12 mg group averaged 18.8% weight reduction versus 5.1% with placebo, using the treatment-regimen analysis.7
Both findings can be valid. TRIUMPH-1 and TRIUMPH-2 enrolled different populations; comparing their headline percentages does not isolate the effect of diabetes or provide a formula for forecasting an individual’s result.
Individual outcomes also should not be read from a group label alone. A trial target describes an assigned treatment arm; tolerability and continued participation are part of the experience. The retatrutide, tirzepatide and semaglutide comparison identifies the populations and durations behind other commonly quoted results.
Did weight loss continue beyond 80 weeks?
Yes, a selected TRIUMPH-1 extension supplied longer follow-up. It enrolled 532 participants with starting BMI of at least 35 who completed 80 weeks and tolerated their assigned treatment. They continued for 24 weeks with escalation to a maximum tolerated 9 or 12 mg dose.5
Among extension participants originally assigned 12 mg, average reduction reached 30.3% at 104 weeks in the efficacy analysis. This was a selected subgroup, not the result for every person originally randomized.5
The extension addresses continued treatment in eligible completers. It should not be attached to the overall trial’s earlier average as though the same whole population supplied both points. Subtracting an overall 80-week average from the selected extension result would not calculate the exact additional loss experienced by that subgroup.
How does tolerability affect the before-and-after picture?
In TRIUMPH-1, 11.3% of the 12 mg group discontinued because of adverse events, compared with 4.9% with placebo.9
This is why the analysis matters. A result that accounts for treatment discontinuation addresses a different question from an estimate under continued treatment. Headline percentages should be read with that distinction, rather than treated as guaranteed outcomes for everyone starting therapy.
A useful treatment discussion includes appetite benefit, ability to maintain nutrition, symptoms and whether the planned schedule remains appropriate. Ongoing vomiting or difficulty keeping fluids down warrants medical assessment. The retatrutide side-effects guide covers the reported digestive effects, altered skin sensations and when symptoms need attention.
What happens after stopping retatrutide?
The dedicated TRIUMPH-6 maintenance study is designed around this question: after an 80-week retatrutide lead-in, a 36-week randomized phase compares continuing the same dose, a different dose or switching to placebo.8
Its public record describes the study design, so it cannot supply a percentage of weight regained after withdrawal. Likewise, the continued-treatment extension above does not measure the experience of stopping.
Maintenance, dose reduction and discontinuation are distinct choices. A long-term plan needs to address how appetite, weight, nutrition and other health needs will be managed after the initial reduction. Trial duration does not establish a short on/off cycle or a personal tapering schedule. The dosage and treatment-duration guide keeps these protocol questions together.
Can the trial results be applied to a research vial or pen?
The before-and-after findings here describe investigational treatment within identified clinical studies. As of 3 November 2026, retatrutide remained investigational and was not an approved medicine.10
A research product’s stated amount or format does not demonstrate that it will reproduce a trial outcome. Clinical efficacy data and a product’s batch documents answer different questions.
Visit retatrutide buying information to compare the listed vial and pen formats, quantities and documentation. For the complete explanation of appetite, waist and metabolic findings, continue to the benefits and research guide.
Sources and original records
Original research, official prescribing information and named product documents. Each numerical result refers to the stated population, timeframe and analysis.
- 01Retatrutide obesity phase 2 trial ↗
Jastreboff et al. · NEJM · 2023. Actual 24- and 48-week weight outcomes; continued group weight reduction through week 48.
- 02TRIUMPH-1: published phase 3 obesity results ↗
Jastreboff et al. · NEJM · 29 September 2026. Adults without diabetes; 80-week treatment-regimen estimates.
- 03Published participant accounts from the phase 2 trial ↗
Goetz et al. · Obesity Pillars · 24 October 2025. Qualitative interviews; selected sample with 36 retatrutide recipients.
- 04Hunger and eating behavior during treatment ↗
Kanu et al. · Diabetes, Obesity and Metabolism · 2025. Exploratory questionnaire analysis at weeks 24 and 48.
- 05TRIUMPH-1 waist results and selected 104-week extension ↗
Lilly · 21 May 2026. Efficacy-analysis waist data and the selected longer-treatment subgroup.
- 06DXA body-composition substudy ↗
Coskun et al. · Lancet Diabetes & Endocrinology · 2025. Adults with type 2 diabetes; on-treatment scan analysis.
- 07TRIUMPH-2: obesity and type 2 diabetes ↗
The Lancet · Online 29 September 2026. Separate phase 3 population; 80-week treatment-regimen outcomes.
- 08TRIUMPH-6 maintenance study record ↗
Lilly · NCT06859268. Maintenance study design, checked 3 November 2026; not a withdrawal-results report.
- 09TRIUMPH-1 protocol and adverse-event discontinuation ↗
Lilly · 6 June 2026. Original sponsor report; TRIUMPH-1 dosing stages and discontinuation data.
- 10Official retatrutide development status ↗
Lilly. Current status checked 3 November 2026; future-dated material excluded.