No definitive smoking gun on alcohol use has yet been presented, but the evidence leans heavily against it. Two very large direct studies and one huge meta study have recently appeared, and they largely point to increased risk of dementia as well as of cardiometabolic disease (includes stroke, coronary heart disease, and diabetes).
Media articles:
No healthy level of alcohol consumption, says major study
There’s no risk-free amount of alcohol, population-level study finds
Study:
Alcohol use and burden for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016
Media articles:
Heavy Drinking Tied to Early-Onset Dementia in French Study
Study:
Contribution of alcohol use disorders to the burden of dementia in France 2008–13: a nationwide retrospective cohort study.
Media article:
Both long term abstinence and heavy drinking may increase dementia risk
Editorial:
Relation between alcohol consumption in midlife and dementia in late life (Editorial)
Study:
Alcohol consumption and risk of dementia: 23 year follow-up of Whitehall II cohort study
All of the links have been added to Alzheimers > Risk Factors and Health > Diet