Any Level of Alcohol Consumption Increases Risk of Dementia A comprehensive new study led by the University of Oxford, Yale University, and the University of Cambridge has found that any amount of alcohol consumption increases the risk of developing dementia. This challenges prior beliefs suggesting light-to-moderate drinking might protect against dementia. The findings are published in BMJ Evidence-Based Medicine. --- Background Alcohol consumption is common worldwide and linked to many health risks. Heavy drinking has long been associated with higher dementia risk. Previous studies presented mixed findings about moderate drinking; some suggested moderate alcohol intake might reduce dementia risk. Recent brain imaging studies indicate even low alcohol consumption could raise dementia risk. --- Study Overview The study analyzed data from over 500,000 participants in two large cohorts: US Million Veteran Program UK Biobank Examined self-reported alcohol consumption and dementia incidence. Included genetic analyses involving more than 2.4 million participants from 45 studies to assess causal relationships. Genetic data helped distinguish true causation from correlations. --- Key Findings Observational data initially suggested: Low/moderate drinkers had lower dementia risk than non-drinkers or heavy drinkers. However, some non-drinkers were former heavy drinkers, which may inflate their risk. Genetic evidence revealed: A steady increase in dementia risk with increasing alcohol consumption. No protective effect of alcohol at any level. Quantified risks: Doubling genetically-predicted risk of alcohol use disorder was linked to a 16% increased dementia risk. Tripling the number of alcoholic drinks per week corresponded to a 15% higher risk. People who developed dementia often reduced alcohol intake before diagnosis, potentially misleading earlier observational findings. --- Expert Comments Dr Anya Topiwala (Oxford Population Health): Genetic data contradicts the belief that light drinking benefits brain health; even moderate drinking may raise dementia risk, highlighting the importance of reducing alcohol consumption for dementia prevention. Dr Stephen Burgess (University of Cambridge): Genetic comparisons allow clearer conclusions on causation, reinforcing that greater alcohol use leads to higher dementia risk for everyone. Dr Joel Gelernter (Yale University): This work updates clinical understanding, opposing past medical assumptions of brain benefits from light drinking. --- Implications The study indicates no safe threshold for alcohol consumption with respect to brain health, supporting public health strategies to reduce alcohol use as a means to help prevent dementia. --- Reference Study title: "Alcohol use and risk of dementia in diverse populations: evidence from cohort, case–control and Mendelian randomisation approaches" Published in: BMJ Evidence-Based Medicine (24 Sep 2025) --- Related Links University of Oxford News Oxford Population Health Support Oxford Research Research Jobs at Oxford --- Image credit: Getty Images (SolStock)