Drinking just a glass of wine or pint of beer each night in middle-age may age your brain by two years, a study claims.
Researchers analysed MRI scans of 36,000 adults to calculate their brain size, and then compared the alcohol intake of the volunteers.
Their results suggested a 50-year-old who drank one unit a day — the equivalent of half a lower-strength lager beer — would have a brain six months older than if they kept off the booze.
University of Pennsylvania researchers found the link grew even stronger the more people drank.
Middle-aged adults who consumed two units a day — one medium-sized glass of red or white wine — had a brain two-and-a-half years older, the data implied.
Increasing the number of units to four per day resulted in an extra ten years of aging compared to abstinence.
Professor Remi Daviet, one of the researchers, said: ‘Cutting back on that final drink of the night might have a big effect in terms of brain aging.’
The findings mark another twist in the evolving field about the risks of alcohol, and question claims that low-level drinking can have benefits.
University of Pennsylvania researchers have found drinking just three pints a week can cause your brain to age by an extra half a year
A glass of wine with dinner – rather than on its own – cuts risk of type 2 diabetes, study finds
You shouldn’t feel guilty for having a glass of wine every night — so long as you drink it with dinner, like the French.
A study has found enjoying a glass with your meal, rather than on its own, could cut your risk of type 2 diabetes.
The researchers discovered that people who drank wine with their meals were 14 per cent less likely to develop the condition, compared to those who drank wine without food.
However, those who drank beer or spirits with their meals appeared to be at higher risk of the metabolic disease.
Lead author Dr Hao Ma of Tulane University, New Orleans, said: ‘Drinking moderate amounts of wine with meals may prevent type 2 diabetes if you do not have another health condition that may be negatively affected by moderate alcohol consumption and in consultation with your doctor.’
Previous studies have identified a compound present in the skin of grapes, known as polyphenols, as being able to lower blood sugar levels.
Wine, especially red, is also rich in healthy plant chemicals such as resveratrol that acts as an antioxidant.
The study, published in Nature Communications, tracked people’s drinking habits using data from the UK biobank.
Lead author Professor Gideon Nave, a neuroscientist, said: ‘Having this dataset is like having a microscope or a telescope with a more powerful lens.
‘You get a better resolution and start seeing patterns and associations you couldn’t before.
‘The fact we have such a large sample size allows us to find subtle patterns — even between drinking the equivalent of half a beer and one beer a day.’
They checked MRI scan records of patients aged between 40 and 69 to see how much white and grey matter they had in the brain. One scan was used for each individual.
Grey matter is the main part of the brain that processes information, whereas white matter acts as the lines of communication.
Participants answered a survey that asked them about how much they drank, from nothing to four units a day.
The team controlled for other factors that may have skewed the results, including age, height, sex, smoking status, income, genetic ancestry and where people lived.
They used statistical models to calculate how increasing drinking would affect the brain age of a 50-year-old.
Going from one unit a day to two saw their brains age a further two years.
And increasing from two units to three units a day saw brains age another three-and-a-half years on top of that.
Professor Daviet said: ‘There is some evidence that the effect of drinking on the brain is exponential.
‘One additional drink in a day could have more of an impact than any of the previous drinks that day.’
The research could have ramifications for national drinking guidelines, the researchers said.
Professor Henry Krazler, a psychiatrist and one of the authors, added: ‘These findings contrast with scientific and [US] governmental guidelines on safe drinking limits.
The NHS recommends that adults drink no more than 14 units each week — that’s 14 single shots of spirit or six pints of beer or a bottle and a half of wine
‘For example, although the National Institute on Alcohol Abuse and Alcoholism recommends that women consume an average of no more than one drink per day, recommended limits for men are twice that.
‘[This is] an amount that exceeds the consumption level associated in the study with decreased brain volume.’
The NHS recommends that adults drink no more than 14 units each week — that’s 14 single shots of spirit or six pints of beer or a bottle and a half of wine.
Despite showing an increased risk to brain ageing from drinking more, the team did not look into how binge drinking affected cognitive decline compared to daily consumption.
Professor Nave said: ‘This study looked at average consumption, but we’re curious whether drinking one beer a day is better than drinking none during the week and then seven on the weekend.
‘There’s some evidence that binge drinking is worse for the brain, but we haven’t looked closely at that yet.’
Previous research had shown an association between drinking more and lower brain volume, but experts have yet to discover why exactly this takes place.
DO YOU DRINK TOO MUCH ALCOHOL? THE 10 QUESTIONS THAT REVEAL YOUR RISK
One screening tool used widely by medical professionals is the AUDIT (Alcohol Use Disorders Identification Tests). Developed in collaboration with the World Health Organisation, the 10-question test is considered to be the gold standard in helping to determine if someone has alcohol abuse problems.
The test has been reproduced here with permission from the WHO.
To complete it, answer each question and note down the corresponding score.
0-7: You are within the sensible drinking range and have a low risk of alcohol-related problems.
Over 8: Indicate harmful or hazardous drinking.
8-15: Medium level of risk. Drinking at your current level puts you at risk of developing problems with your health and life in general, such as work and relationships. Consider cutting down (see below for tips).
16-19: Higher risk of complications from alcohol. Cutting back on your own may be difficult at this level, as you may be dependent, so you may need professional help from your GP and/or a counsellor.
20 and over: Possible dependence. Your drinking is already causing you problems, and you could very well be dependent. You should definitely consider stopping gradually or at least reduce your drinking. You should seek professional help to ascertain the level of your dependence and the safest way to withdraw from alcohol.
Severe dependence may need medically assisted withdrawal, or detox, in a hospital or a specialist clinic. This is due to the likelihood of severe alcohol withdrawal symptoms in the first 48 hours needing specialist treatment.