PEOPLE who drink the equivalent of three large glasses of wine a night can suffer brain damage similar to that seen in chronic alcoholics, research suggests.

Scientists found that people who consumed more than 100 drinks a month — around 130 units — suffered from loss of memory, reduced intelligence, poor balance and impaired mental agility.

The American research team, from Vanderbilt University and the University of California, used magnetic resonance technology to scan the brains of 46 heavy social drinkers and 52 light drinkers.

In the report, published in Alcoholism: Clinical and Experimental Research, the scientists concluded: “Socially functioning heavy drinkers often do not recognise that their level of drinking constitutes a problem that warrants treatment.”

Participants were tested for verbal intelligence, processing speed, balance, working memory, spatial function and learning and memory ability. The heavy drinkers, who consumed over 100 drinks per month, had minor brain damage that affected their ability to do everyday tasks.

“Our heavy drinkers sample was significantly impaired on measures of working memory, processing speed, attention, executive function, and balance,” Dieter Meyerhoff, lead researcher from the University of California, said.

One drink is defined as a measure of spirits, a glass of wine or a can or bottle of beer.

Dr Meyerhoff and Peter Martin, director of the Vanderbilt Addiction Centre, added that brain chemicals and structures among the heavy social drinkers showed similarities to the damage found among chronic alcoholics in hospital or treatment centres.

Brain malfunctions linked to alcohol included the inability to apply consequences from past actions, difficulties with abstract concepts of time and money and difficulties with storing and retrieving information.

“What our findings indicate is that brain damage is detectable in heavy drinkers who are not in treatment and function relatively well in the community,” Dr Meyerhoff said.

“Our message is: drink in moderation. Heavy drinking damages your brain ever so slightly, reducing your cognitive functioning in ways that may not be readily noticeable. To be safe, don’t overdo it.”

Anne Jenkins, of Alcohol Concern, said that the findings underlined the need for people to drink in moderation and be made aware that the health risks did not only apply to alcoholics. People tended to equate heavy drinking “with a street drinker having three-litre bottles of cider,” she said.

“They don’t necessarily equate it with heavy social drinking - the man who goes out regularly and has three or four pints or three large glasses of wine - which is what we are talking about.

Ms Jenkins said that the study was an important contribution to the alcohol debate, as most knowledge about brain damage due to chronic drinking had been gathered only from alcoholics.

“What this study shows is that if you regularly drink that sort of quantity, it does begin to have an affect on the brain and cognitive powers. It pushes home the point that it’s so important to drink in moderation.”

The findings follows a survey that suggests about a quarter of Britons think alcohol is good for their health and almost one in five are convinced it relieves stress.

Only nine per cent of those polled by Mintel believed alcohol was bad for people, while 13 per cent said their social life would not be the same without a drink in hand.

Of 1,000 adults who took part in the January survey, three quarters thought there was nothing wrong with alcohol in moderate quantities and 26 per cent said alcohol was good for the health. Some 17 per cent said alcohol was “great at relieving stress”.

• A patch designed to help drinkers to cut down on alcohol, while also weaning them off cigarettes, is being developed by scientists. The sticking plaster, which can be worn anywhere, carries a chemical compound called mecamylamine, which is known to reduce the desire to drink. A team from Duke University in the US is developing the patch, which will also contain nicotine, reducing the interlinked urges of having a drink and a smoke.

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