GLP-1 drugs like semaglutide—best known for treating diabetes and driving weight loss under the brand names Ozempic and Wegovy—may also deliver a surprising mental health boost. In a massive study tracking nearly 100,000 people over more than a decade, researchers found that these medications were linked to significantly fewer psychiatric hospital visits and sick days.
The findings, published recently in The Lancet Psychiatry, represent one of the largest investigations to date into the mental health effects of these blockbuster medications, which have generated billions in revenue while transforming obesity and diabetes treatment.
The Swedish registry study included 95,490 people (56,976 female and 38,514 male) with a mean age of 50.6 years. Of these participants, 22,480 individuals used GLP-1 receptor agonists during the follow-up period, which tracked participants from 2009 to 2022 using Swedish national health registers.
During periods when people were taking semaglutide, psychiatric-related hospital care and sick leave dropped by 42% compared with periods when they were not using these medications. The risk of depression was 44% lower, while anxiety disorders were reduced by 38%.
The study found particularly striking results for substance use disorders, with hospital care and work absence linked to substance use 47% lower during periods of semaglutide use. The medications were also associated with reduced risk of suicidal behavior.
The research used a sophisticated “within-individual” design that compared periods when the same people were taking the medications versus when they were not, helping to control for other factors that might influence mental health outcomes.
Semaglutide emerged as the most effective GLP-1 receptor agonist among those studied, followed by liraglutide. According to the study data, compared with non-use of GLP-1 receptor agonists, semaglutide showed an adjusted hazard ratio of 0.58 (95% CI 0.51–0.65) and liraglutide showed 0.82 (0.76–0.89) for lower risk of worsening mental illness.
The findings come as health officials have grappled with mixed signals about GLP-1 drugs and mental health. In 2023, European regulators began investigating reports of mood changes and suicidal thoughts among users. However, the FDA has been reviewing available data on the relationship between GLP-1 medications and suicidal behavior, with ongoing regulatory discussions about safety labeling.
The strength of the results caught attention in the medical community, though researchers emphasize that because the study relied on registry data, it cannot prove exactly how or why these medications influence mental health.
The implications could extend far beyond individual patients. Millions of Americans are currently taking GLP-1 medications, with usage continuing to grow rapidly. If the mental health benefits prove causal, they could reshape treatment approaches for patients who struggle with both metabolic and psychiatric conditions.
According to the study authors, for anxiety and depression that co-occur with diabetes and obesity, semaglutide and, to a lesser extent, liraglutide might offer dually effective therapeutic options. However, they emphasize that randomized controlled trials evaluating these findings are warranted before clinical practice changes.
The researchers propose several potential mechanisms for the observed mental health benefits. Weight loss-related improvements in body image, relief associated with better blood sugar control in diabetes patients, and reduced alcohol consumption could all play roles. Additionally, there may be direct neurobiological mechanisms at work, potentially involving changes in the brain’s reward system.
Previous research has suggested connections between GLP-1 medications and reduced alcohol use disorders in Swedish registry data, which could have downstream effects on mood and anxiety disorders. This aligns with the current study’s findings of reduced substance use-related hospitalizations and sick leave.
The study’s authors caution that more research is needed before doctors begin prescribing GLP-1 drugs primarily for mental health benefits. The current approved uses remain diabetes management and weight loss in appropriate patients.
However, for patients already prescribed these medications for metabolic conditions who also experience depression or anxiety, the findings suggest they may be getting additional mental health benefits. This could be particularly relevant given that depression and anxiety commonly co-occur with obesity and diabetes.
The research adds to growing evidence that metabolic and mental health are interconnected in complex ways. As GLP-1 medications become increasingly common in clinical practice, understanding their full range of effects becomes more crucial for healthcare providers.
The study’s large scale and long follow-up period provide robust data, but the researchers emphasize that controlled trials specifically designed to test mental health outcomes are needed to establish causation and guide clinical decision-making.
For now, the findings offer encouraging signals that these widely-used medications may provide broader health benefits than originally recognized, potentially addressing multiple health challenges simultaneously in appropriate patients.