Alcohol Consumption and Adverse Mental and Physical Health Outcomes: A Systematic Review With Complementary Physical Health Findings and Biological Mechanistic Context

Alcohol consumption, heavy drinking occasions and alcohol use disorder (AUD) represent distinct exposures. This systematic review examined psychiatric outcomes, with selected physical-health findings and biological mechanisms considered as context. PubMed, Scopus and Web of Science Core Collection were searched on 14 October 2026 for articles published during 2015–2025, without language restrictions. Two reviewers independently screened records and assessed eligibility; no protocol was prospectively registered. Of 5,185 records, 2,879 duplicates were removed, 2,306 records were screened, 53 reports were assessed and 28 reports were included in the principal synthesis. Study-specific estimates were summarized by exposure, comparator, population and outcome. Pooling was not undertaken because the candidate estimates differed materially in exposure definitions, reference groups, age and sex composition, and symptom-based versus diagnostic endpoints. In young women, extremely frequent versus very infrequent binge drinking was associated with subsequent depressive symptoms (adjusted odds ratio [OR] 1.30, 95% confidence interval [CI] 1.04–1.63). In older women, problem drinking versus nondrinking was associated with incident depressive symptoms (OR 2.11, 95% CI 1.12–4.00) and anxiety symptoms (OR 2.22, 95% CI 1.01–4.86). In a mixed-sex Dutch cohort, AUD versus no AUD was associated with first-onset anxiety disorder (OR 2.03, 95% CI 1.17–3.51). Suicidal outcomes showed adverse associations in several settings, but estimates differed in design and precision. The Kangwha cohort provided study-specific log-linear alcohol-volume evidence for suicide mortality. Secondary physical-health evidence was not comprehensively identified by domain-specific searches. Residual confounding, overlapping cohorts, selected populations, sparse events and limited methodological assessment restrict causal interpretation. Biological mechanisms provide plausibility context rather than evidence of mediation.