Moderate alcohol consumption linked with higher iron levels and poorer thinking skills

14 July 2022

UK researchers have found moderate alcohol consumption is linked with higher iron levels in a region of the brain and was associated with poorer thinking skills. The scientific journal, PLOS Medicine, published the findings today (Thursday 14 July).

What did the researchers do?

Researchers asked 20,965 UK volunteers to self-report their alcohol consumption. The researchers also looked at iron levels in the brains using an MRI scan. They also looked at iron levels in the blood and liver and measured thinking skills.

What did they find?

Alcohol consumption above seven units weekly was associated with higher iron levels in a part of the brain called the basal ganglia. This brain region is responsible for movement.

Seven units is roughly equivalent to about three quarters of a bottle of wine, or three pints of beer.

Markers of higher levels of iron in this region were linked with poorer brain thinking skills including speed and reaction times.

Our expert opinion on the findings

Dr Sara Imarisio, Head of Research at Alzheimer’s Research UK, said:
“Our brains are incredibly complex, responsible for our memories, as well as what we think, feel and do. By keeping our brains healthy as we age, we can help stave off diseases like Alzheimer’s which physically attack it, striking at the very essence of who we are.

“While there’s no definitively safe level of alcohol consumption, research into how smaller amounts of alcohol can contribute to poorer brain health is an active research area. In this large study researchers asked volunteers to self-report their alcohol intake, while looking at the levels of iron in volunteers’ bodies, including their brains. This study points to an increased amount of iron as one potential mechanism for poorer brain health related to alcohol consumption, however the study can’t say for sure that this relationship is causal.

“It’s not clear how a build-up of iron affects dementia risk, and Alzheimer’s Research UK is funding research at the University of Oxford to further our understanding of how changes in iron levels track with other brain changes that occur in diseases like Alzheimer’s.

“This study didn’t look at dementia, or alcohol as a risk factor for the condition, but there are many good health reasons to keep an eye on how much alcohol you’re drinking. As well as only drinking in moderation, staying physically, mentally and socially active, eating a healthy balanced diet, not smoking, and keeping weight, cholesterol and blood pressure in check are all good ways to keep the brain healthy as we age.”