Young people who drink heavily are 80 percent more likely to contract sexually transmitted infections (STIs), a University of Otago study shows.
The research, the first to quantify the relationship in New Zealand between youth drinking and getting an STI, found that one in 10 of the heaviest drinkers contracted an STI between age 15 to 30.
Lead researcher Joe Boden said it was not surprising to find a link between loosening of inhibitions associated with drinking and increased chance of contracting STIs.
What was disappointing was the degree to which young people appeared to be ignoring the safe sex messages they as a "post-HIV" generation had been exposed to, Dr Boden said.
"These are people who grew up in the post AIDS era and have had loads of education about safe sex and the risks of STIs. They are getting complacent and the safe sex message is going out the window when they drink."
Mr Boden and his colleagues interviewed 1000 people over a period of 15 years at ages 15, 18, 21, 25 and 30.
One in 10 of heaviest drinkers, who made up 100 of the participants, contracted at least one STI between age 15 and 30.
In the second-heaviest group of drinkers one in 19 people contracted an STI, compared to one in 24 people for the lightest group of drinkers.
Between ages 22 and 25 - which was the period of heaviest drinking for all groups - heavy drinkers consumed on average 51 standard units of alcohol a week, the second heaviest 11 and the lightest drinkers 1.5.