Young women with a love of ready-to-drink (RTD) alcohol mixes are out-drinking some groups of men and women, a new Massey University study shows.
The research, the first of its kind, saw 2000 people interviewed and then categorised in distinct "clusters" of drinkers.
One of the major findings was women under the age of 24 who bought RTDs on average drank almost 24 litres a year.
That figure is twice that of the next group of female problem drinkers and more than the heaviest drinking men.
It's a problem which has grown over a generation, with researchers Martin Wall and Sally Casswell going back to data from the mid-1980s and found nothing as significant.
The study grouped men into four distinct groups and women into 14.
Perhaps unsurprisingly, men consumed a "relatively high proportion" of beer.
Women however, has a small number of extreme clusters; some mainly drank spirits-based RTDs while others drank mostly wine.
"Those in the higher consuming clusters were more likely to have signs of alcohol dependency, to report lower satisfaction with their health, to like alcohol ads and to have purchased alcohol late at night.
Dr Wall believes some of the changes in drinking behaviour can be traced back to the introduction of supermarkets being able to sell alcohol in the 1990s.
Before that, when people went to off-licences it was clear buying alcohol was the reason they were there, Dr Wall told Fairfax Media.
"With supermarkets, it's just part of the weekly shop. We do speculate that that change may have been a factor for increasing drinking among women."
Auckland addiction treatment clinician Simone Barclay said the change in female drinking could be linked to societal changes.
"One flipside of woman's changing roles is 'girls can do anything', girls are less lady-like - and so they should be. [Heavy drinking] is one way it is manifesting, they're drinking just like the lads," she said.
The study was published in Alcoholism: Clinical and Experimental Research.