GLP-1 Agonists Improve Well-being, But Not Depression

People feel better on these weight loos drugs — but they don’t change clinical depression

STUDY: Hung TH et al, Human Psychopharmacology: Clinical and Experimental 2026;41:e70041

STUDY TYPE: Systematic review and meta-analysis

FUNDING: NIHR Advanced Fellowship

Background

1 in 8 US adults take a GLP-1 receptor agonists like semaglutide, liraglutide, tirzepatide, exenatide; usually for obesity but also for type 2 diabetes. Many say these medications improve mental health, but they failed in the first clinical trial of depression. This study adds clarity to that discrepancy.

The Study

This meta-analysis pooled 35 RCTs: 25 trials (17,751 participants) measured psychological well-being, and 11 trials (1,961 participants) measured depressive symptoms using validated depression scales. Populations included patients with type 2 diabetes, obesity, Parkinson’s disease, binge eating disorder, and alcohol use disorder. Study duration ranged from 17 to 160 weeks.

GLP-1 agonists produced a small but statistically significant improvement in psychological well-being (SMD = 0.37) compared to controls. Effects were consistent across semaglutide, liraglutide, and tirzepatide, and strongest with subcutaneous administration. By contrast, GLP-1 agonists had no significant effect on depressive symptoms (SMD = 0.08), and this null result held across every drug, diagnosis, and subgroup examined. GRADE certainty of evidence was low for both outcomes.

Practice Implications

1. Somethings improve well-being and treat depression, like brisk walking, Mediterranean diet, and sunlight. Not so with GLP-1 agonists.
2. People may feel better on GLP-1RAs because they’re losing weight, controlling their blood sugar, and experiencing less physical disability, rather than a direct antidepressant effect.