If you’re using Mounjaro (Tirzepatide) for weight loss, you’re probably curious about how much you might lose and over what time frame. Everyone’s journey is unique, but clinical trials and patient experiences provide helpful guidance.
The SURMOUNT clinical trials are the main studies examining Mounjaro’s effects on weight loss in adults with overweight or obesity, both with and without type 2 diabetes. These trials combined medication with lifestyle support and tracked results over time.
Surmount-1: 15% average weight loss over 18 months
This study looked at people without diabetes, and ran for 72 weeks (about 18 months). At the end of the study, participants taking Mounjaro:
- Lost an average of 15% of their body weight on the 5mg dose
- Lost up to 20.9% at the highest 15 mg dose
- Compared to 3.1% weight loss in the placebo group [Reference - 1].
Surmount-2: 12.8% to 14.7% weight loss over 18 months
This study looked at people with type 2 diabetes and also lasting 72 weeks, showed the following results:
- Weight loss between 12.8% and 14.7% on 10mg and 15mg respectively
- Compared with 3.2% in the placebo group [Reference - 2].
Surmount-3: sustained and increased weight loss for over 12 months
Extended research on the findings previously, this research showed sustained and sometimes increased weight loss over periods longer than one year, particularly when combined with intensive lifestyle changes [Reference - 3].
Surmount-4: 25.3% average weight loss over 88 weeks
This research focused on maintenance of weight loss. Participants who continued treatment with Tirzepatide experienced a mean weight reduction of 25.3% over 88 weeks, compared to 9.9% in the placebo group [Reference - 4].
These results reflect cumulative weight loss over the entire study periods. Weight loss is gradual, with progress building over months. It is worth noting that these are averages from large groups of participants. Individual results may vary, and weight loss depends on many factors such as medication dose, lifestyle (diet and exercise), sleep and stress management and overall health.
How much weight can I lose on Mounjaro?
Weight loss with Mounjaro usually happens gradually and steadily. Here’s what many people experience along the way:
- Month 1: You may notice your appetite starting to reduce and smaller portion sizes. Weight loss is typically small but begins early.
- Months 2–3: Many begin to see clearer changes in their weight and feel more control over cravings.
- Month 6: Significant weight loss and improvements in energy and mobility are often seen by this point.
- 12 to 18 Months: By the end of one year or longer, many patients reach milestones of 10–20% weight loss or more. Some may experience plateaus, which is when your weight loss stalls and is a normal part of weight management.
Tips for Successful Weight Loss on Mounjaro
There are a few things that you can do for successful weight loss whilst on Mounjaro:
- Eat balanced meals with protein, complex carbohydrates, and healthy fats to stay full and energised.
- Stay hydrated.
- Include gentle exercise daily.
- Prioritise good sleep and stress management.
- Take your medication as prescribed.
- Track your progress in a motivating way.
If your weight loss is slower than expected, discuss it with Phlo Clinic; adjustments and support are available.
Mounjaro supports weight loss over time but works best alongside healthy lifestyle changes and medical guidance. The SURMOUNT trials have shown that significant weight loss is possible when Mounjaro is used consistently, but progress can vary from person to person.
Weight loss is rarely linear. Plateaus and slower periods are a normal part of the journey. Focus on your health improvements and how you feel day to day. Every positive step counts.
References
- Wilding, J. P. H., Batterham, R. L., Calanna, S., et al. (2022). Once-weekly tirzepatide for weight loss in patients with obesity. New England Journal of Medicine, 387(3), 205–216. https://doi.org/10.1056/NEJMoa2206038
- Garvey, W. T., Frias, J. P., Jastreboff, A. M., le Roux, C. W., Sattar, N., Aizenberg, D., Mao, H., Zhang, S., Ahmad, N. N., Bunck, M. C., Benabbad, I., Zhang, X. M., & SURMOUNT-2 investigators (2023). Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial. Lancet (London, England), 402(10402), 613–626. https://doi.org/10.1016/S0140-6736(23)01200-X
- Gibble, T. H., Cao, D., Forrester, T., Fraseur Brumm, J., & Chao, A. M. (2025). Tirzepatide and health-related quality of life in adults with obesity or overweight: Results from the SURMOUNT-3 phase 3 randomized trial. Diabetes, obesity & metabolism, 27(8), 4268–4279. https://doi.org/10.1111/dom.16463
- Aronne, L. J., Sattar, N., Horn, D. B., Bays, H. E., Wharton, S., Lin, W. Y., Ahmad, N. N., Zhang, S., Liao, R., Bunck, M. C., Jouravskaya, I., Murphy, M. A., & SURMOUNT-4 Investigators (2024). Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial. JAMA, 331(1), 38–48. https://doi.org/10.1001/jama.2023.24945
