It probably doesn’t take a genius to work out that drinking too much alcohol isn’t good for our health. The science has been clear on this for decades.
Still, much mystery surrounds exactly what effects alcohol can have, and whether small helpings of certain types of our favourite beverages can have some benefits.
But an emerging line of research is shedding more light on how alcohol impacts our bodies – and how it ages them.
And we’re not just talking about age in the ‘amount of candles of your birthday cake’ sense, either. Unlike chronological age, which counts the years we’ve lived, biological age assesses the function and disease risk at the cellular level.
Over decades, scientists have developed several methods to evaluate your biological age, but two stand out for their robust evidence linking alcohol to bodily harm: telomere length and epigenetic age. Here’s how your alcohol consumption could change them.
Drinking can leave your DNA vulnerable to damage
And that’s not a good thing. You may not have ever heard of them before, but telomeres are crucial parts of our genetic make-up. Capping the ends of chromosomes, these repetitive DNA sequences protect them from damage during cell replication.
However, each time cells replicate a portion of telomere is lost; if they become too short, cells can no longer divide and will die.
“Over time these telomeres get progressively shorter because of the incomplete copying,” Anya Topiwala, a consultant psychiatrist at the University of Oxford, tells BBC Science Focus. “So you can use the physical length of these telomeres as a sort of proxy for biological ageing.”
Essentially, you want to keep your telomeres as long as possible for, well, as long as possible – shorter telomere lengths have been linked to age-related diseases like Alzheimer’s, cancer and coronary artery disease.
Back in 2022, Topiwala and her team from Oxford Population Health studied 245,000 participants in the UK to measure how alcohol consumption affects telomere length.
“We found that the more people drank, the shorter these telomeres were. So, therefore, the inference is that alcohol causes biological ageing,” Topiwala says.
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In the observational analysis, they found that drinking more than 29 units of alcohol weekly (approximately ten 250ml glasses of 14 per cent ABV wine) was associated with one to two years of age-related change in telomere length, compared to drinking less than six units per week (about two large 250ml glasses of wine).
Meanwhile, individuals who had alcohol use disorder had aged between 3 and 6 years more.
Exactly how alcohol shortens telomere length, Topiwala says, is unclear. “We think it's most likely to be due to oxidative stress. So alcohol consumption increases free radicals, which reduces the body's natural antioxidants. We think that's probably the mechanism of the shortening.”
Certain types of alcohol are worse for you
Unlike telomere length, which looks at just one biomarker as an estimate of biological age, epigenetic age uses about 100 biomarkers to assess what’s known as DNA methylation, a process closely associated with ageing.
“Epigenetics is the interface between our fixed DNA that we inherited from our parents and the ever-changing environments that we live in, including our lifestyles,” Dr Lifang Hou, a professor of preventive medicine at Northwestern University, tells BBC Science Focus.
Though epigenetic ageing is a relatively new measure, scientists have found that it can reflect unhealthy lifestyle behaviours and act as an early warning sign for disease.
Back in 2023, Hou and her team published a study assessing the effects of alcohol on biological age. “Our study is very unique because we focus on a group of healthy people who don't have any disease yet. We recruited participants and followed them up for 35 years,” Hou says.
Once again, the research found that cumulative alcohol exposure is a surefire way to increase your biological age.
Additionally, they found that the younger you are, the greater the ageing effects. In other words, alcohol's ageing effect is greater the younger you are.
Another interesting finding in Hou’s work was the influence of the type of alcohol. The results showed that people who drank liquor, as opposed to beer or wine, were at greater risk of ageing faster.
Again, the reasons behind many of these effects are not always clear. Hou and her team have more research in the pipeline hoping to understand the link between alcohol and biological ageing in more depth.
“The message is if you drink a lot, or in particular if you drink a lot of liquor cumulatively, then your biological age will increase faster,” Hou says.
Can biological age be reversed?
The good news is that, as both Topiwala and Hou point out, biological ageing can in theory be reversed. The bad news, however, is that in practice we don’t really know how to do it.
“There is a potential mechanism through which there could be a degree of telomere rescue, on a theoretical level. But there's not been a study that's looked into that,” Topiwala says.
Hou adds, “We can’t change our DNA, but then we can change the function of our DNA by adding different chemicals to it. It serves as a switch to turn on or off.
“It's like modification. We can reverse it theoretically if we remove bad environmental factors or anything that caused the epigenetic changes.”
But regardless of whether turning back the biological clock is practically possible, one thing is for certain: stopping or reducing how much you drink will decelerate the ageing process.
And although both studies indicated that drinking more was worse for you – and Hou’s research suggested liquor was particularly bad – neither found any positive effects associated with moderate drinking.
“We can't find any protective effect. It all seems to be harmful and, again, the more you drink, the worse it is,” Topiwala concludes. Hou agrees. “In the past, there have been studies suggesting that drinking moderate amounts of red wine could be beneficial for cardiovascular health, but in our data, we didn’t find any evidence that this can slow the biological ageing process. We didn’t see any beneficial effect,” she says.
About our experts
Anya Topiwala qualified in medicine from the University of Oxford and subsequently pursued specialist training in older adult psychiatry. In 2017, she completed a DPhil in Psychiatry based on the MRC-funded study "Predicting MRI abnormalities with longitudinal data of the Whitehall II Substudy". In 2019, Topiwala was awarded a Wellcome Trust Clinical Research Career Development Fellowship to investigate the effect of mechanistic pathways through which alcohol consumption impacts brain health. Using huge databases, which contain lifestyle and clinical data on millions of people in the UK and US, and the largest brain imaging and genetic samples worldwide, her work aims to clarify how alcohol affects brain structure and function.
Lifang Hou, MD, MS, PhD is a professor of preventive medicine. With a multidisciplinary background in medicine, basic science, and epidemiology, Dr. Hou’s research interest lies in integrating traditional epidemiologic methods with the ever-advancing molecular techniques in multi-disciplinary research focusing on identifying key molecular markers and understanding their potential impact on disease aetiology, detection, and prevention. In addition to being a principal investigator (PI) of several National Institutes of Health-funded grants, Hou is the co-director and Co-PI of the Northwestern Consortium for Early Phase Cancer Prevention Trials of the Division of Cancer Prevention (DCP) Consortia, National Cancer Institute.
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