Research

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Tobacco smoking significantly increases the prospective risk of developing depression in both adults and adolescents.

Smoking is a significant risk factor for developing depression in both adults and adolescents. Quitting smoking can help reduce this risk. While quitting may be challenging, the long-term mental health benefits are substantial.

ModerateSupportsMEDIUM confidence
Among 52,568 adults, from seven studies with 1-6 year follow-ups, smoking significantly increased the prospective risk of depression... A meta-analysis of six studies including 15,333 adolescents aged 13-19 showed that smokers were significantly more likely to develop depression than non-smokers over 1-6 year follow-up (OR=1.73, 95% CI: 1.32-2.4).
Joseph Firth et al. · World Psychiatry · 2020

Why this rating

Based on meta-analyses of prospective studies, but quality scores were low to fair, and heterogeneity was notable.

Source

A meta‐review of “lifestyle psychiatry”: the role of exercise, smoking, diet and sleep in the prevention and treatment of mental disorders

Joseph Firth et al. · World Psychiatry · 2020

DOI 10.1002/wps.20773

Meta-analysis · 45 studiesCited 1,042×
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DOI resolved against Crossref · corpus check 2026-06-10

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