This new research published in PLOS Medicine, involved 20,965 participants from the UK Biobank who reported on their own alcohol consumption. Brain scans using magnetic resonance imaging (MRI) were carried out on all participants, and 7,000 also had their livers imaged to assess levels of systemic iron. All individuals completed a series of simple tests to assess cognitive and motor function
Exploring the relationships between alcohol consumption and brain iron levels, the research team, led by Anya Topiwala, Big Data Institute (BDI), University of Oxford, found that alcohol consumption above seven units per week was associated with markers of higher iron in the basal ganglia, a group of brain regions associated with control of motor movements, procedural learning, eye movement, cognition, emotion, and more. Iron accumulation in some brain regions was associated with cognitive function.
The average alcohol intake was around 18 units per week, which translates to about seven and a half cans of beer or six large glasses of wine.
Dr Anya Topiwala, Senior Clinical Researcher, Big Data Institute, said:
'In the largest study to date, we found that drinking greater than seven units of alcohol weekly was associated with iron accumulation in the brain. Higher brain iron in turn is linked to poorer cognitive performance, such as executive function (problem solving) and fluid intelligence (puzzle tasks). Iron accumulation could underlie alcohol-related cognitive decline.'
Professor Klaus Ebmeier, Department of Psychiatry, University of Oxford, added:
This is one in a series of Oxford studies in the large UK Biobank data set that suggest even "normal" drinking comes with a risk of faster ageing, impaired mental, and physical brain health. All who consume alcohol need to balance this against their potential enjoyment of having a drink.