Exposure to alcohol marketing and films with images of sexy drinking could entice people to drink twice as much as they normally would, a conference on alcohol harm heard yesterday.

The results of an alcohol experiment were presented to the Politics of Alcohol conference in Wellington yesterday by Netherlands-based professor Peter Anderson, one of the leading public health authorities on alcohol in the world.

Forty male university students from the Netherlands were split randomly into two groups.

One watched an hour of 40 Days and 40 Nights, which included three scenes of drinking and 15 additional alcohol images.

The other watched an hour of American Pie 2, which had 18 scenes of drinking and 23 extra alcohol-related images.

During a movie break, both groups were split in half again and one half was shown an alcohol commercial, the other half a non-alcohol commercial.

The experiment took place in a setting with a fridge full of wine, beer and soft drinks, and the students were free to drink as they wanted.

Those who watched American Pie 2 and saw the alcohol commercial had 2.98 drinks on average, almost twice as many as the 1.51 drinks consumed by those that saw 40 Days and 40 Nights and watched the advertisement that had nothing to do with alcohol.

"Advertising and imagery have a major impact on the real-time drinking of young people," Professor Anderson said.

The Government is being criticised for its plans for alcohol reform, which ignore most of the Law Commission's recommendations on advertising and sponsorship, including an eventual ban on all advertising except for objective product information.

The Alcohol Reform Bill is expected to be reported back to Parliament by the middle of next month, though it is unclear if it will be passed into law before the election.

National MP Chester Borrows, chairman of the select committee considering the bill, said it was difficult to strike the right balance on an issue where everyone blamed each other, but few wanted higher prices or less access to alcohol.

"Everybody's view is that drinking is bad but that it's everybody else's drinking, not my drinking."

Under questioning, he admitted the bill did not have any requirement for parents to properly supervise drinking in a private home.

It was a "hole" in the law that was not addressed because the bill aimed to tackle harm through supply.

Professor Anderson also cited Australian research in trying to answer the question of how much you have to drink to kill yourself: six drinks a day would give you a 10 per cent chance of an alcohol-related death, regardless of gender.

Professor Doug Sellman, director of the National Addiction Centre, challenged the Government's line that alcohol and smoking should be treated differently.

American Pie 2 (movie with lots of drinking): 2.38 drinks.

40 Days and 40 Nights (movie with not much drinking): 1.73 drinks.

An alcohol advertisement: 2.42 drinks.

A non-alcohol advertisement: 1.69 drinks.

American Pie 2 and an alcohol ad: 2.98 drinks.

40 Days and 40 Nights and a non-alcohol advertisement: 1.51 drinks.