The more a person drank, the more likely they were to have hippocampal atrophy – a form of brain damage that affects memory and spatial navigation, which is regarded as an early marker for Alzheimer’s disease.
But, even moderate drinkers – classed for the study’s purposes as drinking between 11 and 17 standard drinks ( between 14 and 21 UK units) a week – were three times more likely to have hippocampal atrophy than teetotallers.
The HSE guidelines are 11 standard drinks spread out over the week for women and 17 standard drinks for men. A standard drink is a small glass of wine or a pub measure of spirits or half pint.
Experts from the University of Oxford and University College London studied 550 civil servants over a 30-year period, repeatedly assessing their alcohol consumption and cognition.
The researchers examined images of the participants’ brains – which enabled them to explore correlations between average alcohol use, cognition and brain structure.
They found that alcohol use was associated with reduced right hippocampal volume.
The brain images, taken using MRI scanners, also showed that those who consumed high amounts of alcohol were also more likely to have reduced white matter integrity.
These drinkers also showed a faster decline in language fluency – tested by how many words beginning with a specific letter can be generated in one minute.
The authors wrote: “We found increased odds of hippocampal atrophy at just 14-21 units a week, and we found no support for a protective effect of light consumption on brain structure.
“Alcohol might represent a modifiable risk factor for cognitive impairment, and primary prevention interventions targeted to later life could be too late.”