NEW YORK - STUDENTS in co-ed college accommodation are more likely to binge drink and have more sex, according to a US study that may confirm parents' worries.

A survey of more than 500 students at five US universities found that students living in co-ed housing were 2.5 times more likely than those in all-male or all-female dorms to admit to binge-drinking on a weekly basis.

They were also more than twice as likely to say they'd had at least three sex partners in the past year.

The findings, published in the Journal of American College Health, may not surprise many college students.

"A lot of the reaction we've been getting from students is, 'Well, we've known that,'" said researcher Brian Willoughby, who conducted the study while at the University of Minnesota in St. Paul and is now a visiting professor at Brigham Young University in Salt Lake City.

Mr Willoughby told Reuters Health that the findings should make more universities, researchers and parents aware of the issue.

He said 90 per cent of university housing in the United States is now co-ed - part of a larger move away from the traditional notion that colleges should act as stand-ins for parents and enforce rules on students' social behavior. 'This transition to co-ed housing has happened without an evaluation of its effects,' Mr Willoughby said.

In the study, Mr Willoughby and colleague Jason Carroll found that more than 41 per cent of students in co-ed housing said they binged on a weekly basis compared to less than 18 per cent of those in single-sex dorms.

While 63 per cent of students in single-sex housing said they'd had no sexual partners in the past year, this was true of only 44 per cent of students in co-ed dorms.

Among students in co-ed housing, almost 13 per cent said they had had three or more sexual partners in the past year, compared with 5 per cent of students in single-sex dorms.