Drinking alcohol within government guidelines still harms the brain, heart and liver, study finds

Drinking any amount of alcohol, even within government guidelines, still has a toxic effect on our organs, a new study suggests.

A team of researchers at Imperial University London have studied MRI scans of approximately 10,000 people aged between 40-69 years to investigate whether there is a “safe level” of alcohol consumption.

Under the current UK guidelines, men and women should avoid drinking more than 14 units of alcohol per week, the equivalent of 10 small glasses of low-strength wine or six pints of average strength beer.

The study, published in the eLife Sciences journal, found that all alcohol consumption, even below the current recommended limit, causes measurable pathological, structural and functional changes in the brain, heart and liver.

Researchers said that while excessive alcohol intake is a well-known risk factor for increased liver fat, evidence regarding low-to-moderate alcohol consumption had previously been inconclusive.

They said their findings were consistent with a previous 2011 study which found that moderate consumption of red wine for three months increases liver fat.

“Our results imply that there is not a ‘safe threshold’ below which there are no toxic effects of alcohol,” the study’s authors said, adding that current public health guidelines “may need to be revisited”.

John Holmes, a professor in alcohol policy and deputy director of the Sheffield Alcohol Research Group, said that while the study provides evidence that drinking small amounts of alcohol is not risk-free, it “does not provide any compelling reason to change the current guidelines”.

“The UK’s drinking guidelines provide advice on ‘low risk’ alcohol consumption, not ‘no risk’ alcohol consumption.  As such, they are set at a level meaning the average person will have only a very small risk of dying due to alcohol. 

“The guidelines take account of evidence that drinking small amounts of alcohol still carries some risk to people’s health, particularly in relation to cancer, but also for other health conditions,” he said.

Tim Spector, professor of genetic epidemiology at King’s College London, has questioned the findings on the basis that the researchers did not examine MRI scans from a comparative group of people who do not drink.

“This is an observational study of around 10,000 60-year-olds without any control group that don’t drink.  While the risk of some MRI detected changes in the brain and heart increased with alcohol intakes, the risks these imply for an individual are unclear.  

“It is hard to put these risks in context against, say, the risk of driving a car which also has no lower risk limit or the risk of eating junk food that is likely much higher,” he said.

He also pointed to previous research in favour of moderate alcohol consumption, such as studies linking red wine to increased heart protection.

“While it is correct to point out the dangers of alcohol, these major limitations mean we should be wary of issuing any new guidelines that are unlikely to fit everyone,” he said.

Mark Leyshon, senior research and policy manager at Alcohol Change UK, said there is poor public awareness of key information relating to the risks of drinking alcohol.

“We’re of the belief that people have a right to know the risks – simply put, that the more we drink, the bigger the risk becomes of developing alcohol-related health problems, and this study serves as a useful reminder.

He added: “There remains poor public awareness of key information relating to the risks of drinking alcohol – what the current low-risk drinking guidelines are; the increased risks of health problems that regularly drinking above these guidelines brings; and the more specific details about what particular illnesses, like cancer, are linked to regular heavy drinking.”

He said the government needs to implement measures that will “reduce harm and save lives, like better regulation of alcohol marketing, and addressing alcohol pricing and tax so that litres of strong alcohol can no longer be purchased at pocket money prices”.