Drinking just half of NHS safe weekly booze limit ‘could harm your brain’

NHS health officials have long stated a daily pint of beer is relatively safe.

But drinking just half that amount could leave you prone to long-term memory issues, a study suggests.

Researchers found drinking seven-plus units — the equivalent of three pints of beer, or five small glasses of wine — a week may lead up to a build-up of iron in the brain.

Accumulation of the mineral has been linked to causing Alzheimer’s and Parkinson’s.

It could also explain how drinking too much alcohol over time can lead to cognitive decline, experts say. 

The NHS recommends people do not drink more than 14 units a week and to spread them over three days or more

The study of nearly 21,000 middle-aged Brits measured iron deposits in the brain in people who drank between zero and 33 units a week.

The NHS recommends people do not drink more than 14 units a week and to spread them over three days or more. 

People who drank seven or more units per week had an eight per cent higher chance of developing iron deposits in one key part of the brain — the bilateral putamen.

An Oxford University-led team of researchers found those with higher deposits also performed worse on memory, logic and reasoning tests.

Long-term alcohol use has long been linked to cognitive decline and even dementia but researchers claim this study has uncovered ‘a potential mechanism’ behind the trend.

The study, published in PLOS Medicine, looked at MRI brain scans in 20,956 adults in Newcastle, Stockport and Reading from 2006 to 2010. Participants were aged 40 to 69. 

Scientists also asked them what kind of drinks and how many of them they drank every week to calculate their units intake.

Less than 3 per cent of participants never drank, while most drank around 18 units per week — the equivalent of six large glasses of wine.

They were split into five groups, based on how much they drank.

The team then tested people on their cognitive skills to see whether their deposits affected brain performance.

One of the tests got people to draw a line between numbered dots as quickly and accurately as possible to measure their motor skills.

A memory challenge asked them to recall shapes over different time-lengths after seeing them on a screen.  

And a third quiz, designed to assess their logic and reasoning skills, asked them to solve abstract questions.

Dr Anya Topiwala, a psychiatrist at the University of Oxford, said: ‘In the largest study to date, we found drinking greater than 7 units of alcohol weekly associated with iron accumulation in the brain. 

‘Higher brain iron in turn linked to poorer cognitive performance. Iron accumulation could underlie alcohol-related cognitive decline.’

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.

YOUR 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.