High Iron Levels Found In Brains Of Moderate Alcohol Drinkers
Certain degenerative neurologic diseases such as Parkinson’s Disease and Alzheimer’s Disease are associated with higher levels of iron deposits in the brain. People with high levels of alcohol consumption are also found to have higher levels of iron in the brain. These iron deposits can contribute to issues such as slowed cognition, coordination and movement.
What had not been studied until recently is the impact of moderate alcohol consumption on iron deposits in the brain. A group of researchers based primarily at the University of Oxford, United Kingdom, but also with contributors from Yale University and the University of Cambridge, published their findings regarding iron deposition in the brains of moderate alcohol drinkers in this week’s PLOS Medicine.
When considering daily habits related to health, alcohol consumption has increasingly had a mixed bag. While it is oftentimes considered harmful at any amount, studies looking at red wine consumption in particular have evaluated the cardiovascular benefits of the red wine-containing substance resveratrol. The evidence has been inconsistent at best, and has been confounded with other potentially healthy habits such as a Mediterranean diet, frequent social interaction, and low-fat consumption in red wine drinkers.
This study engaged over 20,000 adult volunteer participants from the United Kingdom (UK) Biobank. Each subject self-reported their weekly alcohol consumption, whereby “moderate” alcohol consumption was considered to be 56 grams of alcohol (ethanol) per week. A 12-ounce beer contains 14 grams of alcohol, as does a 5-ounce glass of wine or a 1.5 ounce glass of spirits such as gin or vodka. Moderate alcohol consumption in this study means a total of four glasses of wine, beer, or spirits per week.
Study participants underwent brain Magnetic Resonance Imaging (MRI) as well as liver imaging. Those who reported what was considered to be “moderate” alcohol consumption (56 grams, or four drinks per week) were found to have higher levels of iron in their brains and livers than those who reported “low” or “no” weekly alcohol consumption. The authors assessed both objective as well as subjective cognitive and motor functions, including short-term memory tests and self-reported walking speeds. They did not find any obvious markers for slowed cognition or movement in the moderate alcohol consumers. However, they note “Brain iron is likely to be an early marker of disease, and participants may have been examined too early in the process to detect clinical manifestations.”
The authors acknowledge that, while important, their data is preliminary, as there are so many factors that are associated with iron deposition, including age, diet and genetics, and a study which relies on self-reporting may have inherent errors, especially when it comes to self-reporting of lifestyle habits. Nonetheless, this is the first large population study to find an association (nope, we can’t even come close to calling it a cause) between alcohol consumption and iron deposits in the brain.
Iron deposition in the brain is a clearly defined factor associated with neurologic disease. Most of these disorders have no relationship to alcohol intake, but alcohol intake alone may be a contributing factor to brain changes, earlier than we thought, and with much less weekly alcohol consumption than we had thought.