Drinking more than the recommended weekly limits can be bad for a person’s brain health, a new study has shown.
The study found that alcohol consumption is associated with an increased risk of adverse brain outcomes and a steeper decline in cognitive abilities.
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.
And 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.
Even moderate drinkers – classed for the study’s purposes as drinking between 14 and 21 units a week – were three times more likely to have hippocampal atrophy than abstainers.
Last year, the Government changed its guidance on drinking and urged both men and women to drink no more than 14 units each week – the equivalent of six pints of average strength beer.
They also found that very light drinking – classed as drinking between one and six units a week – had no protective effect compared to abstinence.
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: “Our findings support the recent reduction in UK safe limits and call into question the current US guidelines, which suggest that up to 24.5 units a week is safe for men, as 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.”
The study is published in The British Medical Journal.
