Higher prices for alcohol will do little to reduce high-intensity drinking because binge drinkers commonly drink little or nothing on some days so they can binge on the weekend, leading public health experts warn.
At the same time, new evidence shows a polarisation of Australian habits, with the heaviest drinkers consuming more while light drinkers are consuming less and more people are abstaining.
Concern over alcohol-related violence has prompted demands to increase the price of alcohol. But data shows that far from being cheap, Australia is already one of the most expensive countries in which to buy alcohol. Of more than 190 countries, discount beer in Australia is the second most expensive, and spirits the seventh most expensive.
Table wine in Australia is the second most expensive of Organisation for Economic Co-operation and Development countries.
But while price can influence consumption - the cheaper the alcohol, the more people drink - the effect on high-intensity consumption is less clear.
''When you use a blunt instrument like taxation, which affects everyone, it doesn't necessarily affect everyone evenly,'' said Griffith University health economist Josh Byrnes.
Binge drinkers in Australia tend to respond to higher prices by adjusting their buying patterns rather than their behaviour, says a peer-reviewed study led by Dr Byrnes and Anthony Shakeshaft, deputy director of the National Drug and Alcohol Research Centre (NDARC).
When prices go up, high-intensity drinkers simply have more days when they consume little or nothing to save their money for binges.
''[Binge drinking] is people's preferred way of drinking, so they're going to use the money they spend on alcohol in a way that fits in with their preferred pattern,'' Professor Shakeshaft said. ''If the price goes up and people have less money to spend on alcohol, they're not going to change their drinking behaviour, they'll just find ways to maintain that behaviour.''
Meanwhile, new research shows drinking habits are diverging.
''Generally speaking, when drinking changes, it changes evenly across the whole distribution. If drinking goes up 10 per cent, heavy drinkers and light drinkers alike are drinking 10 per cent more,'' said NDARC researcher Michael Livingston. ''Now what we're seeing is a breakdown of that pattern.
''We've seen in Australia no real change in [overall] consumption but an increase in very heavy drinking offset by reductions in light drinking.'' There is also evidence of a sharp decline in teen drinking and lower consumption among the ageing population.
''People tend to drink a bit less as they get older,'' Dr Livingston said. ''Our population has a bigger bubble of people in their 60s and 70s, so that consumption's got to be offset somewhere else.''
The reason for the change is unclear. Part of the problem is that researchers haven't captured how much the heaviest drinkers are consuming. ''It could be that the levels of harm we're seeing now are actually associated with higher levels of consumption than what we think, precisely because people are under-reporting what they drink,'' said Professor Shakeshaft.
University of Melbourne sociologist Robin Room, who has directed alcohol and drug research centres in the US, Canada, Sweden and Australia, said US researchers determined ''five-plus'' drinks as the cut-off that later became the basis for international surveys. ''It was because they didn't dare ask about more.''