Even moderate drinking can damage the brain, new study shows

A new study conducted by British scientists concluded that even moderate drinking may be enough to damage the brain, NHS reports.

Scientists from the University of Oxford and University College London conducted a study that spanned over 30 years and looked at 550 adults’ weekly alcohol intake, cognitive performance over time and the structure of their brain at the end of the study.

The participants’ alcohol consumption was labelled as “abstinent” – with consumption of less than one unit of alcohol a week, “light drinking” – between one and less than seven units, “moderate drinking” – as seven to less than 14 units a week for women and seven to less than 21 units for men and “unsafe drinking” – according to pre-2016 (21 units a week for men and 14 units for women) and to newly revised UK Department of Health guidelines (more than 14 units for men and women).

The researchers used brain scans and various cognitive tests, such as lexical fluency (in which participants were asked to name as many words beginning with same letter as possible) or Rey-Osterrieth complex figure test (where they were asked to reproduce a complex line drawing) and discovered that the damage of the brain progressively increased as the alcohol consumption was larger, too.

While the scientists saw no association between the ”light” drinkers and brain damage, people who drank at least seven units of alcohol per week were less able to name words beginning with the same letter, but there was no difference in any other cognitive test.

“The finding that alcohol consumption in moderate quantities is associated with multiple markers of abnormal brain structure and cognitive function has important potential public health implications for a large sector of the population,” scientists concluded.

“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,” they further added.

Nevertheless, the study did have some limitations, which means that the results may not be applicable to the UK as a whole. For example, the alcohol consumption was self-reported, so it might have inaccuracies, and the MRI scan took place only once and at the end of the study, so it is rather difficult to rule out other factors that may have impacted the brain structure.

For reference, 14 units of alcohol are the equivalent of six pints of beer.