New Delhi: The World Health Organisation (WHO) recently stated that no amount of alcohol can be considered good for one’s health. In continuation of the same, a new large-scale study found that drinking even a small amount of alcohol can raise dementia risk. For several years, studies have found that drinking a glass of wine with dinner, or a glass of beer, could be beneficial for the heart. However, these were proven misleading and incorrect, thereby encouraging many to stop drinking altogether.
How does alcohol affect the brain?
The latest study, led by Dr. Anya Topiwala, a senior clinical researcher at the University of Oxford, used a different approach. By combining traditional observation with genetic analysis, her team was able to separate lifestyle effects from other confounding factors. The study was published in the BMJ Evidence-Based Medicine journal.
“The genetic analyses showed that even small amounts of alcohol could increase dementia risk,” Topiwala explained. “This is the largest study to date, and the use of Mendelian randomisation allowed us to look at lifetime exposure, not just drinking habits in midlife.”
Mendelian randomisation is a method that uses genetic markers linked to alcohol consumption. Because such genetic traits are determined at birth, they are not influenced by memory lapses or lifestyle changes. They reduce the odds of errors that can distort results in a self-reported study. The findings suggest that dementia risk rises steadily with alcohol consumption. For example, drinking three alcoholic beverages a week was associated with a 15% higher risk of dementia compared with just one drink a week. Similarly, doubling genetic risk factors for alcohol dependence increased dementia risk by 16%.
Experts not involved in the study say the results add weight to what scientists have long suspected: alcohol, even in small amounts, is not harmless to the brain. Dr. Richard Isaacson, a neurologist and director of research at the Institute for Neurodegenerative Diseases in Florida, noted that alcohol is particularly concerning for people with the APOE4 gene variant, the most common genetic risk factor for Alzheimer’s disease. Two drinks late at night on an empty stomach, for instance, may do more damage than the occasional drink with food earlier in the evening.
The study drew on two massive data sources: the UK Biobank, which tracks the health of about 560,000 people, and the U.S. Million Veteran Program, which includes participants of European, African, and Latin American descent. Observational data from these groups showed that heavy drinkers faced the highest risk of dementia, but surprisingly, people who never drank had a similar risk to those who drank heavily. Genetic analysis, however, clarified that alcohol exposure itself likely drives the problem. Although the research stops short of proving that alcohol directly causes dementia, it strengthens the case that no amount of drinking is truly safe for brain health.