Alcohol consumption in excess amounts has adverse effects on both physical and mental health, but whether it can cause permanent cognitive damage or not is unclear. The objective of this study is to investigate the association between alcohol consumption and the risk of dementia.

This is a prospective cohort study that included a total of 9,087 participants, and the alcohol consumption was measured as the mean from the following assessments: abstinence, 1-14 units/week, and more than 14 units a week. The primary outcome of the study was incident dementia identified through mental health services, mortality registers, and linkage to hospital.

During the mean follow-up of 23 years, a total of 397 cases of dementia were reported. Abstinence of alcohol in midlife was associated with a higher risk of dementia (HR 1.47) compared with 1-14 units a week. Among participants drinking more than 14 units a week, a 7-unit increase in alcohol consumption was associated with a 17% increased risk of dementia.

The research concluded that the risk of dementia was increased in people who abstained from alcohol during the midlife or consumed more than 14 units per week. Alcohol consumption between 1-14 units was associated with the least risk of dementia.