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Even moderate drinking can damage your brain, new research says

The study monitored more than 500 people over 30 years.

Image: Shutterstock/Africa Studio

MODERATE ALCOHOL CONSUMPTION can damage a person’s brain, researchers have claimed.

Researchers from the University of Oxford and University College London monitored the alcohol intake and cognitive performance of 550 men and women in the UK for over 30 years, from 1985 to 2015.

The research, published in the British Medical Journal, notes that none of the participants were “alcohol dependent”. Their mean age was 43 years and 23 people were excluded from the results because of poor data or others issues.

At the end of the study, researchers conducted MRI scans of the participants’ brains.

After taking into account factors such as age, gender and social activity, researchers found that people who drank more often had a shrunken hippocampus – which is thought to be the centre of emotion, memory and the autonomic nervous system.

While those consuming over 30 units a week were at the highest risk compared with people who didn’t drink, even those drinking moderately (14-21 units/week) had three times the odds of the right side of their hippocampus being affected.

The research found there was no protective effect of light drinking (1-<7 units/week) over abstinence. Higher alcohol use was also associated with faster decline in lexical fluency (vocabulary). No association was found with word recall.


In Ireland, the weekly alcohol consumption guidelines are up to 11 standard drinks in a week for women and up to 17 standard drinks in a week for men.

A standard drink (also called a unit) here has about 10 grams of pure alcohol in it. In the UK, a standard drink has about eight grams of pure alcohol.

F1.large (1) Source: BMJ

In the study, researchers note that the following was already known about this topic:

  • Heavy drinking is associated with Korsakoff’s syndrome (a chronic memory disorder), dementia, and widespread brain atrophy (a loss of neurons)
  • While smaller amounts of alcohol have been linked to protection against cognitive impairment, few studies have examined the effects of moderate alcohol consumption on the brain
  • Previous studies have methodological limitations and have provided conflicting findings

They state that the new research finds:

  • Compared with abstinence, moderate alcohol intake is associated with increased risk of adverse brain outcomes and steeper cognitive decline
  • The hippocampus is particularly vulnerable, which has not been previously linked negatively with moderate alcohol use
  • No protective effect was found for drinking small amounts of alcohol over abstinence, in contrast to previous reports

In the paper, the authors state: “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.”

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About the author:

Órla Ryan

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