Heavy drinking has long been linked to a greater risk of Alzheimer’s disease – but scientists now believe people whose faces flush after drinking alcohol may be especially vulnerable.
A new study from the University of Florida examined how a toxic byproduct of alcohol may reshape the brain at a cellular level.
Researchers focused on acetaldehyde, a harmful compound produced when the body breaks down alcohol, and a gene variant linked to the so-called alcohol flush reaction.
The gene, ALDH2, provides instructions for making an enzyme that helps convert acetaldehyde into acetate, a less toxic substance that can be more easily processed and cleared by the body.
But some people carry a faulty version of the gene, known as ALDH2*2, which means they clear acetaldehyde less efficiently.
This can cause acetaldehyde to build up after drinking, triggering symptoms such as facial flushing, nausea, headaches and a racing heart.
In the study, researchers used mice genetically engineered to carry the ALDH2*2 variant to examine how acetaldehyde toxicity from chronic heavy alcohol use may influence brain inflammation, metabolic dysfunction and tau pathology – a hallmark of Alzheimer’s disease.
‘People carrying this variant struggle to clear acetaldehyde efficiently, allowing this toxic compound to linger like an unwelcome guest and fuel inflammation and oxidative stress throughout the body, including the brain,’ said Nagalakshmi Balasubramanian, the study’s lead author.
Just a couple of glasses a wine a night could increase your risk of developing Alzheimer’s, especially if your prone to flushing, new research has suggested
Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP.
‘While carrying this variant does not mean someone is destined to develop Alzheimer’s disease, it may stack the deck toward accelerated ageing and neurodegeneration, especially in people with chronic heavy alcohol exposure.’
She added that heavy drinking – generally defined as more than eight drinks per week for women or 15 for men over long periods – may leave a lasting imprint on brain health.
The research – which was presented at the annual meeting of the Research Society on Alcohol – also aimed to find out whether boosting ALDH2 activity could help the brain fight back against alcohol-induced damage.
They concluded that identifying these molecular ‘red flags’ and genetic variations early may ‘pave the way for earlier detection and more targeted human therapies before irreversible brain damage takes hold.
‘Research suggests that chronic alcohol use can fast-track biological aging in the brain and ‘fan the flames’ of pathways linked to Alzheimer’s,’ Balasubramanian added.
‘Alcohol can trigger inflammation, oxidative stress and metabolic dysfunction while also contributing to depression, anxiety and social withdrawal, changes that are often early warning signs of the disease.
‘In many cases, the writing may be on the wall long before memory loss appears.
‘When it comes to protecting brain health, knowledge truly is power.’
This study isn’t the first one to suggest that cutting down on alcohol consumption could play a significant role in preventing the disease.
Recent research found drinking any amount of alcohol may increase the risk of developing dementia.
The study, led by experts at the Universities of Oxford, Cambridge and Yale looked at data from 559,559 people and found people who did not drink at all , and those who drank heavily had higher dementia risk than light drinkers.
However, researchers said this was likely to be the result of people with early symptoms cutting back on or giving up alcohol entirely.
There are an estimated one million people in the UK living with dementia – and by 2040 that figure is expected to climb to 1.4 million.
But while the search for a cure continues, there is mounting evidence that prevention may be the best form of defence for now.
A major consensus earlier this year by world-leading experts, building on The Lancet Commission on Dementia concluded that almost half of all cases globally could be prevented, or at least delayed for several years, if action was taken to address 14 risk factors – ranging from smoking and excess alcohol consumption, to loneliness and a sedentary lifestyle – that are driving up rates of illness.
NHS guidelines state adults shouldn’t drink more than 14 units a week, the equivalent of one medium glass of wine a night.
