Bright Light Therapy Is Effective for Nonseasonal Depressive Disorders

Is bright light therapy effective treatment for adults with non-seasonal depressive disorders?

This updated meta-analysis of 11 individual trials published since 2000 found evidence to support the benefit of bright light therapy as an effective treatment or adjunctive treatment for adults with nonseasonal depressive disorders. (Level of Evidence = 1a)

Investigators searched multiple databases, including Medline, EMBASE, SCOPUS, Web of Science, PsychINFO, and the Cochrane database, for English language–only randomized trials that compared bright light therapy alone or bright light therapy plus an antidepressant with placebo, antidepressant monotherapy, or dim red light in adults with nonseasonal depression. Bright light therapy was defined as using a fluorescent light box that produces 10,000 lux of white light for at least 30 minutes daily. Two people independently assessed individual trials for inclusion criteria and risk of bias using the Cochrane Risk of Bias tool. Disagreements were resolved by consensus discussion with a third reviewer. All 11 trials (N = 858) that met inclusion criteria were scored at low risk of bias.

Statistically significant higher remission and response rates occurred in the bright light therapy groups than in the non– bright light therapy groups (40.7% vs 23.5% and 60.4% vs 38.6%, respectively). A subgroup analysis found a similar benefit to bright light therapy for improving remission and response rates in trials lasting less than 4 weeks and in trials lasting more than 4 weeks. Additional analyses found minimal heterogeneity among the individual trials and a low probability of publication bias.

Study design: Meta-analysis (randomized controlled trials)

Funding source: Unknown/not stated

Setting: Various (meta-analysis)

Reference: Menegaz de Almeida A, Aquino de Moraes FC, Cavalcanti Souza ME, et al. Bright light therapy for nonseasonal depressive disorders: a systematic review and meta-analysis. JAMA Psychiatry. 2025;82(1):38-46.