Even light drinking could increase dementia risk

Drinking any amount of alcohol could increase the risk of developing dementia, according to a UK study.

The findings challenge the idea that light drinking could benefit brain health, researchers said.

They also suggest that cutting down alcohol consumption across the population could “play a significant role in dementia prevention”.

The study, led by experts at the University of Oxford, Yale University, and the University of Cambridge, looked at data from 559,559 people involved in the UK Biobank and US Million Veteran Program.

During the follow-up period, some 14,540 people developed dementia.

Researchers found non-drinkers and heavy drinkers, who consumed 40 or more drinks a week, had a 41 per cent higher risk of developing dementia compared to light drinkers, who had fewer than seven alcoholic drinks a week.

This rose to a 51 per cent risk among those who were alcohol-dependent.

Researchers also performed genetic analysis using data from genome-wide association studies (GWAS) of dementia, involving 2.4 million people.

Three measures related to alcohol consumption were used to explore the impact on dementia risk.

These were self-reported weekly drinks, problematic “risky” drinking, and alcohol dependency.

Higher genetic risk for all three exposure levels was associated with an increased risk of dementia.

Dr Anya Topiwala, senior clinical researcher at Oxford Population Health and consultant psychiatrist, said: “Our findings challenge the common belief that low levels of alcohol are beneficial for brain health.

“Genetic evidence offers no support for a protective effect, in fact, it suggests the opposite.

“Even light or moderate drinking may increase the risk of dementia, indicating that reducing alcohol consumption across the population could play a significant role in dementia prevention.”

Dr Joel Gelernter, a professor at Yale University and senior author of the study, said the findings, published in BMJ Evidence Based Medicine, not only add to the understanding of the relationship between alcohol and dementia, but also have “clinical implications”.

“There was a time when medical knowledge seemed to support that light drinking would be beneficial to brain health, and this work adds to the evidence that this is not correct.”

Dr Leah Mursaleen, head of clinical research at Alzheimer’s Research UK, said: “In contrast to other studies, the researchers found that even light alcohol consumption may also increase a person’s risk, when combined with genetic analysis.

“Further research is needed to gain a better understanding of the impact of alcohol use on brain health, and how intervention strategies may reduce dementia risk.”