Just half a glass of wine or one small bottle of beer a day can lead to obesity, diabetes and high blood pressure, warns new research. The risk of metabolic syndrome - a combination of the three life-threatening conditions - rises in tandem with alcohol consumption. A study of almost 27 million adults adds to growing evidence there is no safe level of drinking. It may lead to a rethink on official advice.
Lead author Dr Hye Jung Shin, of the National Medical Centre in Seoul, South Korea, said: "Even light alcohol intake is linked to metabolic syndrome." It can cause high blood sugar and cholesterol - increasing the chance of a heart attack and stroke. Men who downed an average of half a glass of wine or a quarter pint of beer daily, on average, were ten percent more prone to obesity - and metabolic syndrome.
One to two glasses of wine, or up to a pint of beer, was associated with 22 and 25 per cent greater odds, respectively - rising to 34 and 42 per cent beyond this. This was compared to those who never drank. Similar trends were identified in women - although the odd tipple was protective against metabolic syndrome.
Half a glass of wine a day raised the risk of obesity by nine per cent - but reduced the odds of metabolic syndrome by three percent - compared to non-drinkers. Women who supped on average more than two glasses were 22 and 18 percent more likely to develop obesity and metabolic syndrome, respectively.
Dr Shin said: "Consuming more than half a standard alcoholic drink a day is associated with an increased risk of obesity and metabolic syndrome in both men and women - and the risk rises in proportion with alcohol intake."
The study presented at the virtual European and International Congress on Obesity was based on over 14 million men and 12 million women in South Korea. Other factors were taken into account including participants' age, exercise levels, smoking history and income.
Dr Shin and colleagues analysed two years of data from the Korean National Health Insurance System collected in 2015 and 2016. His team defined one standard drink as 14g of alcohol - roughly equivalent to a small (118ml) glass of wine or a 355ml bottle of beer.
In the UK, men and women are women advised not to exceed 14 units of alcohol a week - equal to around six pints of beer or six glasses of wine. Dr Shin said: "There was a significant correlation between alcohol consumption and obesity after adjusting for age, exercise, smoking and income in this population - as well as between alcohol consumption and metabolic syndrome.
"Both men and women who consumed a higher quantity of alcohol had higher odds for obesity. The same results are observed for metabolic syndrome."
He added: "Our results suggest the risk of obesity and metabolic syndrome increases in proportion to alcohol consumption when male and female adults drink more than half a standard drink per day."
They further muddy the waters over whether people should be advised to enjoy a daily tipple. Earlier this year a study found men and women who did were up to 40 per cent more likely to make it to 90 than those who were teetotal - or rarely touched booze. The age-extending effects were confined to those who stuck to one drink a day - binge drinkers died earlier.
Some experts say a small amount of alcohol fuels antioxidants that destroy free radicals - harmful chemicals that can lead to potentially fatal illnesses. However, two years a global study of 28 million people found going teetotal was more protective. The US team estimated one drink a day increased the risk of one of 23 alcohol-related health problems by 0.5 per cent. This rose to seven per cent for those who consumed two drinks a day - and soared to 37 per cent for those who downed five.