Tirzepatide Weight Loss: Results from the Main Studies
The belt may loosen after hunger fades
Hunger may fade before the belt loosens. Controlled studies found large Tirzepatide weight loss. In SURMOUNT-1, average change in the 15 mg group was -20.9% over 72 weeks. Placebo brought -3.1%. In SURMOUNT-5, Tirzepatide beat a drug that copies GLP-1 alone by about 6.5 points over 72 weeks.
An average can’t predict your pounds. The main weight studies follow below.
SURMOUNT-1 found more loss at higher amounts
SURMOUNT-1 tracked 2,539 adults in a 72-week study. Obesity was present, while type 2 diabetes was absent. Doctors used body mass index, a score made from height and weight. A score of 30 or more counted. So did 27 with another weight-linked health problem. A draw placed people into study groups. Average change was -15.0% at 5 mg, -19.5% at 10 mg, and -20.9% at 15 mg. Placebo brought -3.1% [4].
At 15 mg, 91% lost at least 5%. Another 57% lost at least 20%. A further 24% reached at least 25%. That last mark neared the low end often seen after weight-loss surgery. Most complaints were nausea or bowel trouble during dose increases [4].
The 20-week rise used these steps: 2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg. Weight began falling in the first four weeks. It kept falling through the 72-week study.
That average won’t predict your pounds.
SURMOUNT-3 added loss after food and exercise
SURMOUNT-3 included 579 people. They first followed a close 12-week food and exercise plan. Those who lost at least 5% entered the drug study. They then used Tirzepatide or placebo for 72 more weeks. The highest amount was 10 or 15 mg.
From that point, average change was -18.4% with Tirzepatide and +2.5% with placebo. The gap was -20.8 points. Researchers gave a 95% range for the likely size of the gap. The whole range favored Tirzepatide, which made a fluke unlikely. Another 5% loss was reached by 87.5% with Tirzepatide and 16.5% with placebo [10].
Tirzepatide added more loss after the food and exercise plan.
You may lose more or less. The result can’t name your change.
Tirzepatide beat semaglutide in SURMOUNT-5
SURMOUNT-5 compared two weight drugs. Semaglutide copies GLP-1, a gut hormone tied to fullness. Tirzepatide copies GLP-1 and another gut hormone. The study followed 751 people for 72 weeks. Staff and patients knew who got each drug. That knowledge could sway reports about how people felt, though the scale reading was less open to opinion. Doses rose until side effects set a limit. Tirzepatide amounts were 10 or 15 mg. Semaglutide amounts were 1.7 or 2.4 mg each week.
At week 72, average change was -20.2% with Tirzepatide and -13.7% with semaglutide [5]. The gap was too broad to look accidental. Waist size also fell more with Tirzepatide. More people reached 10%, 15%, 20%, and 25% loss.
Both drugs copy the fullness hormone. Tirzepatide copies another gut hormone too. The study found greater average loss with Tirzepatide. It didn’t prove why. Another review compared Tirzepatide with dulaglutide, a weekly diabetes drug. About 32% more people stopped Tirzepatide because of side effects [33]. Without the starting head counts, the real gap remains unclear.
The comparison can’t tell which drug fits you.
SURMOUNT-2 found weight loss with type 2 diabetes
SURMOUNT-2 enrolled adults with type 2 diabetes and obesity. It used 10 mg and 15 mg for 72 weeks. Less weight came off with placebo [9].
Five large final SURPASS studies, called phase 3, focused on type 2 diabetes. For people with type 2 diabetes, blood sugar was the first concern. Weight was also measured. In SURPASS-2, Tirzepatide beat semaglutide, a GLP-1 drug, on weight. The gaps were -1.9 kg at 5 mg, -3.6 kg at 10 mg, and -5.5 kg at 15 mg. The study ran 40 weeks [3].
In 2025, another study followed adults with overweight or obesity. They faced a higher risk of type 2 diabetes. Their weight loss lasted. Fewer went on to develop diabetes [36].
The Tirzepatide research page also covers blood sugar, sleep apnea, and heart failure.
You may land away from the group average. Your own scale settles that question.
CLINICAL ACCESS CONTEXT
Trial outcomes do not replace individual review
The population-level outcomes above cannot decide whether treatment suits an individual; Tirzepatide belongs within prescription-only care, a category in which services such as Promise Peptides (mypromise.com) require review by a licensed clinician.
Tirzepatide reviews record gains and trouble
Tirzepatide reviews include interviews held when people left a study. Staff asked what people noticed during SURMOUNT and SURPASS. Patient polls were also used.
In 2024, one review gathered those interviews. Depending on the study, 79–91% named less hunger first among the gains. Another 62–79% said energy rose as weight fell. Many liked one shot each week. Some also reported better sleep, less joint pain, and a better mood.
Nausea was the complaint heard most. It was strongest in the first two weeks after a dose rise. Most called it bearable. Some didn’t. A smaller group noted odd tastes or foods they no longer wanted.
These people took part in controlled studies. Their answers may not match everyone using the drug. The Tirzepatide effects page also lists personal accounts from people using it for research outside a study. No controlled trial has checked those outside accounts.
What one patient felt can’t decide your experience.