Recent reviews commissioned by the World Health Organization (WHO) reveal that glucagon-like peptide-1 (GLP-1) medications, including tirzepatide, semaglutide, and liraglutide, can lead to significant weight loss in individuals with obesity. While the findings show promise, they also raise critical questions about the integrity of the studies and the long-term safety of these treatments.
Impressive Results with Important Caveats
The three reviews, released on February 11, 2026, conclude that GLP-1 drugs result in greater weight loss compared to placebo treatments over one to two years. These medications have been shown to not only aid in weight reduction but also improve blood sugar levels in patients with type 2 diabetes, particularly those with additional health complications.
According to Juan Franco, co-lead researcher from Heinrich Heine University Düsseldorf, “These drugs have the potential to bring about substantial weight loss, particularly in the first year. It’s an exciting moment after decades of unsuccessful attempts to find effective treatments for people living with obesity.” Yet, the studies also noted that side effects, especially nausea, were common, leading some participants to discontinue treatment.
Despite the positive outcomes, researchers stress the importance of scrutinizing the studies. A significant proportion of the trials were funded by the manufacturers of the drugs, raising concerns about potential conflicts of interest. This could undermine the credibility of the results and highlights the need for independent research to validate these findings.
Understanding Access and Long-Term Effects
The reviews also emphasize the social and commercial determinants of health that affect access to these medications. Currently, high prices limit the availability of semaglutide and tirzepatide, while liraglutide has become more accessible as its patent has expired, allowing for generic alternatives. With the semaglutide patent set to expire in 2026, there may be changes in market dynamics that could improve access.
Moreover, the studies primarily included participants from middle- and high-income countries, leaving regions such as Africa and Southeast Asia underrepresented. Eva Madrid, co-lead researcher from the Universidad de Valparaíso in Chile, stated, “Weight regain after stopping treatment may affect the long-term sustainability of the observed benefits. More independent studies from a public health perspective are needed.”
The WHO aims to use these findings to inform new global guidelines for the use of GLP-1 receptor agonists in obesity treatments. As researchers continue to analyze the long-term impacts and safety profiles of these medications, the call for further independent studies remains critical to ensure equitable access and effective treatment strategies worldwide.
