Differing advice on alcohol consumption confuses drinkers globally

International guidelines for alcohol consumption are so confusing it is enough to turn you to drink.

Scientists who studied low-risk drinking advice around the world concluded that there is a “substantial” risk of misunderstanding.

Guidelines were found to vary greatly, with measurements of the amount of alcohol in a “standard drink” ranging from 8g (Iceland, UK) to 20g (Australia).

In the most conservative countries, “low-risk” consumption meant drinking no more than 10g of alcohol per day for women and 20g for men.

But in Chile, a person can down 56g of alcohol per day and still be considered a low-risk drinker.

According to the HSE, low-risk weekly guidelines for adults are up to 11 standard drinks in a week for women, and up to 17 for men. The HSE also recommends that drinks be spaced out over the week, not consumed in one sitting, and advises that drinking more than the safe levels may cause harm.

In Ireland a standard drink has about 10g of pure alcohol whereas in the UK a standard drink has about 8g. Examples of a standard drink here include a pub measure of spirits (35.5ml), a small glass of wine (12.5% volume), a half pint of beer, or an alcopop (275ml bottle). A bottle of wine at 12.5% alcohol contains about seven standard drinks.

Many nations, including Australia, Portugal, and South Africa, are gender-blind when it comes to drinking guidelines, but some, like the US and Ireland, assign different daily or weekly limits for men and women.

Psychiatrist Keith Humphreys, a professor from Stanford University in the US, who co-led the research, said: “There’s a substantial chance for misunderstanding. A study of the health effects of low-risk drinking in France could be misinterpreted by researchers in the United States who may use a different definition of drinking levels.

“Inconsistent guidelines are also likely to increase scepticism among the public about their accuracy. It is not possible that every country is correct; maybe they are all wrong.”

He added: “If you think your country should have a different definition of a standard drink or low-risk drinking, take heart — there’s probably another country that agrees with you.”

The scientists, writing in the journal Addiction, surveyed the definitions of “standard drink” and “low-risk” drinking in 37 countries.

They found that although the World Health Organisation (WHO) had defined a standard drink as one containing 10g of alcohol, this was not accepted by half the countries studied.

Nor was there any general agreement to follow the WHO’s recommendation that both men and women should limit themselves to two standard drinks per day.

Prof Humphreys said: “More and more countries are trying to give their citizens guidelines about how much alcohol is safe to drink, and for whom.

“At the very least, we should know whether it’s true that women should drink less than men. But even this is unclear.

“We’ve also learned that what constitutes a ‘standard drink’ in each country is far from standard, despite the WHO’s recommendation. But in many cases these guidelines are adopted as public health policy and even printed onto alcoholic beverages without knowing whether people read them, understand them, or change their behaviour as a result.”