New evidence suggests that the introduction of minimum pricing for alcohol, introduced in Wales in 2020, may not curb the habit of more vulnerable consumers.

Experts looked at Scotland, where a minimum unit price (MUP) of 50p per unit (8g) of pure alcohol was set in May 2018 in Scotland as part of a national alcohol strategy designed to curb harmful drinking.

Wales then brought in the same measure in March 2020.

But the study showed that consumption among the 5% of heaviest drinkers in Scotland actually increased after the price control measure was introduced.

Previous research has shown MUP has been associated with larger reductions in consumption among heavier drinkers, overall.

The new study published in BMJ Open, which looked at the impact of MUP on alcohol consumption between Scottish men and women, said consumption fell more in women who tend not to drink as heavily as men.

But it also said the alcohol tax was not associated with reduced consumption in younger, more deprived, or heaviest drinking men — those the policy was primarily designed to target.

After Scotland, Wales and several Eastern European countries adopted MUP, it is now being considered elsewhere.

Evaluations of the policy have been positive overall, showing a general fall in alcohol purchases, use, and heavy drinking, but many of these studies have been based on alcohol sales or household expenditure.

Researchers therefore wanted to assess whether the impact of the Scottish MUP might differ by sex, existing drinking patterns, age, and level of social and economic deprivation.

They drew on data from the KWP Alcovision survey, an ongoing cross-sectional online diary survey of the previous week’s alcohol consumption, which annually samples around 30,000 adults in the UK.

Data for Scottish adults was compared with those of English adults before and after the introduction of the MUP.

Researchers then repeated this, using adults resident in Northern England (North West, North East, and Yorkshire and Humber regions) as a comparison group, on the grounds that the drinking culture in these regions is similar to that of people living in Scotland.

The final analysis included drink diaries completed by 106,490 respondents (53,347 women and 53,143 men) from England and Scotland between 2015 and 2018.

Average reported weekly consumption for all respondents was just under 126g for men and just over 71g for women.

With NHS figures saying there are about 8g of alcohol in one unit, that means men during this timeframe drank about 15 pints a week with women consuming about nine pints.

Analysis of the survey data showed that compared with residents in England, MUP was associated with a drop in reported weekly total alcohol consumption of just under 6g a week — 2.7g in licensed premises and 3.3g elsewhere — representing a fall of just over 6%.

The reductions were larger for women (8.6g a week) than for men (3.3g a week), both when compared with England as a whole and when compared with just Northern England.

And they were greater among heavier drinkers than among lighter drinkers, with the exception of the 5% of heaviest drinking men among whom consumption increased by 10%.