Frequently asked questions about GLP-1 weight loss drugs

Clinical Knowledge

5 minutes read

Published 04/08/2026

Woman in white shirt, standing in a rustic living room, is holding semaglutide injection pen in her hands.

We recently hosted a webinar exploring emerging medical trends from Munich Re’s Life Science Report 2025 that are shaping the future of health care (listen in full here). A significant portion of the discussion focused on GLP-1 drug therapies for weight loss, reflecting the rapid growth of research and real-world experience with these drugs. Attendees raised thoughtful questions about how well GLP‑1s perform across different populations and their potential benefits beyond diabetes and obesity.

In response, Munich Re’s medical team has compiled an FAQ document that includes both questions from the webinar, along with others we commonly receive. This Q&A draws on insights from the Life Science Report and is enriched by Munich Re’s latest analysis on GLP‑1 therapies and mortality risk, a large-scale study to further understand the potential significance of GLP-1 drugs from a life insurance perspective. Together, these perspectives help clarify what is known and what is still emerging about the efficacy and potential of GLP‑1 therapies.¹

1. What is considered to be “successful” weight loss?

A reduction of 5-10% of initial body weight is enough to produce clinical improvements in cardiovascular risk factors such as blood pressure and hemoglobin A1c. However, higher weight loss in the 10-15% range may be necessary for those with fatty liver or obstructive sleep apnea. Studies among bariatric patients have shown lower all-cause mortality rates with weight loss of 15% or more.

In GLP-1 clinical studies, weight loss outcomes of 15-21% have been observed. This is typically considered a successful therapeutic outcome, among the largest seen in pharmacotherapy. Ongoing pharmaceutical research continues to explore treatments that may deliver even greater efficacy.²

2. Does this suggest we should not continue addressing root causes, or is this a bridge to better health?

Addressing the root causes of obesity and investing in preventive interventions remain critically important. In an ideal scenario, effective prevention would reduce or eliminate the need for pharmacologic treatment of obesity. GLP‑1 therapies should be viewed as an adjunctive measure, to be introduced when clinically appropriate, used in combination with lifestyle modifications to diet and exercise.

3. What are the most common side effects?

The most common side effects are nausea, vomiting, diarrhea, and constipation. They generally occur at the start of treatment and during dose escalations, but typically resolve over time. Other complications such as gall bladder issues, bowel obstruction and pancreatitis are rare.

4. Is there an analysis of potential long term negative impacts?

Long‑term outcomes continue to be evaluated with the longest GLP-1 randomized trial having a median follow-up duration of 5.4 years. While the side-effects of GLP-1 drugs are now well established (most often gastrointestinal in nature), significant complications have been relatively infrequent. While these findings are reassuring, ongoing post‑marketing surveillance continues, and definitive long‑term conclusions cannot yet be drawn.³

5. What about the effect on muscle mass?

Intentional weight loss primarily decreases body fat mass, but skeletal muscle mass may also decrease. The clinical significance of this lean mass reduction remains uncertain, as available evidence has not consistently demonstrated associated impairments in physical function. In fact, physical function and mobility may actually improve with weight loss. Current recommendations are that users may need to deliberately increase their daily intake of protein and even more importantly, to increase muscle-strengthening and other exercise measures in users of these medications.

6. Do GLP 1 therapies help prevent associated diseases in adults who are not obese?

GLP-1 receptor agonists do provide cardiovascular disease prevention in adults who are overweight but not yet obese. Renal disease prevention benefits remains consistent in all weight categories. Emerging evidence suggests possible broader disease prevention benefits in non-obese populations.⁴

7. Are there any neurological benefits?

Emerging research suggests that GLP‑1 therapies may have benefits for certain neurodegenerative conditions, including Alzheimer’s and Parkinson’s disease, based primarily on preclinical and early clinical research. However, the current body of evidence is still evolving, and findings to date are not conclusive.

8. What happens when an individual stops taking GLP‑1 medications? Is there weight rebound and increased risk?

Discontinuation of GLP‑1 therapy is often associated with weight regain, underscoring the need for ongoing clinical management to maintain benefits. Similarly, many of the protective effects observed during treatment may diminish once the medication is stopped, highlighting the importance of physician‑guided treatment decisions.

From an insurance standpoint, persistence and compliance must be carefully considered when modeling long‑term outcomes, including potential effects on morbidity and mortality.

9. Do the benefits of GLP‑1 medications such as Ozempic or Wegovy outweigh the risks based on current knowledge?

Based on available evidence, the benefits outweigh the risks when prescribed to appropriate populations. GLP-1 drugs not only reduce weight, but also reduce the risk of many other chronic illnesses. While side-effects are common and may limit adherence, serious complications are rare. The impact of these drugs on mortality and morbidity could be substantial.³

10. Why do insurers and employer programs often focus on certain health factors while overlooking physical activity?

Physical activity is a foundational component of health, and insurers have an opportunity to further strengthen efforts to encourage it. While some insurance coverage includes exercise incentives, there remain opportunities for broader and more effective engagement. Pharmacologic solutions such as GLP‑1 therapies address downstream consequences of obesity, but many of these risks could also be mitigated through a more proactive approach to health maintenance.

References

¹All responses are informed by Nauck, Michael A et al., Glucagon-like receptor agonists and next-generation incretin-based medications: metabolic, cardiovascular, and renal benefits, The Lancet, Volume 407, Issue 10531, February 28, 2026, 892 – 908. Additional primary sources are cited where greater specificity or trial‑level detail is required. ²Elmaleh-Sachs A, Schwartz JL, Bramante CT, Nicklas JM, Gudzune KA, Jay M. Obesity Management in Adults: A Review. JAMA. 2023;330(20):2000-2015. doi:10.1001/jama.2023.19897 ³Gerstein, Hertzel CAbella, Mercedes et al., Dulaglutide and cardiovascular outcomes in type 2 diabetes (REWIND): a double-blind, randomised placebo-controlled trial, The Lancet, Volume 394, Issue 10193, July 13, 2019, 121 – 130 ⁴Galli M, Benenati S, Laudani C, et al. Cardiovascular Effects and Tolerability of GLP-1 Receptor Agonists: A Systematic Review and Meta-Analysis of 99,599 Patients, J Am Coll Cardiol. 2025;86(20):1805-1819. doi:10.1016/j.jacc.2025.08.027 The information provided herein is for general information purposes only and should not be relied upon as professional or medical advice. Clinical decisions regarding GLP‑1 therapies should be made by qualified healthcare professionals based on individual patient circumstances. Munich Re, and its employees, directors, officers, and representatives do not warrant, represent or guarantee the accuracy, completeness, or currency of any of the information provided herein and accept no liability whatsoever arising in any way from the use of or reliance on such information, including liability for direct, indirect, special, incidental or consequential damages.

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Contact the authors

Dr. Tim Meagher

Vice President & Medical Director

Munich Re, Canada (Life)

Email TMeagher@munichre.ca

Dr. Gina Guzman

Vice President & Chief Medical Director

Munich Re Life US

Email gguzman@munichre.com