The Science Behind the Findings

Previous research often pointed to a "U-shaped curve," suggesting both non-drinkers and heavy drinkers had higher dementia rates than light drinkers. However, this new study corrects for critical flaws in that data.

Debunking the Myth

The supposed protective effect was likely due to "reverse causation," where individuals with early cognitive decline naturally reduce their alcohol consumption. This created the false impression that light drinking was protective, when it was actually a symptom of an underlying issue.

Genetic Analysis Confirms Risk

By incorporating genetic analysis through Mendelian randomization, researchers established a clearer cause-and-effect relationship. The data showed:

• Every additional 1–3 alcoholic drinks per week raises dementia risk by 15%.

• Individuals with a diagnosed Alcohol Use Disorder (AUD) face a 51% greater risk of dementia than light drinkers.

• Doubling the genetic risk for alcohol dependence increases dementia risk by 16%.

As noted in clinical commentary, these multi-method findings provide the most robust evidence to date on the topic, according to psychiatrist.com.