Drinking too much alcohol speeds up the body's biological clock, research finds

Person refusing a glass of wine
Researchers say anything more than the equivalent of five glasses of wine per week may speed up the body's biological clock. Photo credit: Getty Images

Any beauty buff will know that drinking excessive alcohol can exacerbate the physical signs of ageing, wreaking havoc on the skin due to dehydration and decreased collagen production. 

However, researchers at the University of Oxford say that anything more than five glasses of wine per week may not just age your appearance, but actually speed up the body's biological clock.

To conduct their research, the scientists examined genetic and health-related data from 245,000 adults in the UK Biobank - a large, long-term biobank study investigating the contributions of genetic predisposition and environmental exposure to the development of disease. Participants were divided by gender and had an average age of 57, according to the study, which was published in the journal Molecular Psychiatry

According to the publication, most of the participants were drinkers, with just 3 percent claiming to have never consumed alcohol.

The researchers discovered that those who drank at least 17 units of alcohol per week had shorter telomeres; protective caps found on the ends of chromosomes that protect the DNA from damage. For comparison, telomeres work similarly to how the 'caps' on the ends of shoelaces prevent the strings from fraying.

Telomeres naturally shorten with age, which can lead to the damage of DNA and a heightened risk of developing conditions such as Alzheimer's, diabetes and heart disease. Research has also linked longer telomeres to a more youthful appearance.

During their research, the scientists looked for tell-tale genetic markers in the participants that have previously been associated with alcohol consumption and alcohol-related disorders.

Analysing the data, the researchers found a significant association between high alcohol intake and shorter telomeres. For example, those who drank 29 units of alcohol a week - the equivalent of roughly 10 large glasses of wine - were one to two years older in terms of telomere length than those who drank less than six units per week - about two large glasses of wine.  

Participants who had been diagnosed with an alcohol use disorder, and therefore likely to have been heavy drinkers, were found to have significantly shorter telomeres than controls; equivalent to between three to six years of biological ageing.

However, the researchers found the association between telomere shortening and alcohol intake only kicked in for people who drank more than the aforementioned 17 units per week; the equivalent of just over five glasses of wine. This indicates that those who consume less than 17 units weekly would not be at risk of alcohol-related telomere shortening.  

The study's lead author and psychiatry expert, Dr Anya Topiwala, said the results suggest that alcohol, particularly at excessive levels, will shorten a person's telomeres.   

"Our results provide another piece of information for clinicians and patients seeking to reduce the harmful effects of excess alcohol," she said, as reported by the Daily Mail.

"Furthermore, the dose of alcohol is important – even reducing drinking could have benefits."

How exactly alcohol consumption is capable of shortening telomeres is yet to be determined, however, the researchers suggest the shortening could be related to increased oxidative stress and inflammation that can damage DNA as the body processes alcohol.

Dr Richard Piper, the chief executive of charity Alcohol Change UK, welcomed the findings, noting that the study demonstrates clear links between consuming alcohol and ageing, as well as indicating a possible link between alcohol and Alzheimer's. 

"The researchers are transparent that this study does not prove a causal link, but they also make a well-argued case about the likely biological mechanism," he said, as reported by the Daily Mail. "In general, there is an ever-larger body of science showing how, exactly, alcohol causes so much ill-health and so many early deaths."

In the UK, the National Health Service (NHS) recommends that adults shouldn't consume more than 14 units each week; the equivalent of 14 single shots of spirit, six pints of beer or a bottle and a half of wine. 

In the United States, the Centers for Disease Control and Prevention (CDC) advises Americans not to consume more than 14 standard drinks per week for men and seven for women.

Drinking excessive amounts of alcohol over many years has already been linked to a plethora of health issues including high blood pressure, a heightened risk of stroke and a range of cancers. 

In New Zealand, the Ministry of Health recommends no more than two standard drinks per day for women or no more than 10 per week, with at least two alcohol-free days weekly. For men, the ministry recommends no more than three standard drinks per day, no more than 15 per week and at least two alcohol-free days weekly.