Interviews with college students found that a shocking 34 percent of male drinkers and 24 percent of females said they had celebrated their 21st birthday by consuming 21 or more drinks, the New York Times reported April 8.

The University of Michigan study, involving 2,518 college students, looked into the "21 at 21" drinking ritual, which often involves drinking shots of liquor. The tradition has been linked to a number of alcohol-overdose deaths among birthday celebrants.

The researchers estimated that half of the men and more than one-third of the women in the study had a blood-alcohol level of 0.26 percent or higher when celebrating their 21st birthday, more than three times the legal limit and a level that placed them at high risk of injury or death.

"I think a lot of people view this as a feel-good rite of passage and don't calibrate what a big risk it is,'' said lead author Kenneth Sher. Researchers worry that videos and photos posted on social-networking sites like Facebook could be encouraging the spread of the 21-at-21 ritual.

On the other hand, Clayton Neighbors of the University of Washington Center for the Study of Health and Risk Behaviors said that research has shown that Internet-based interventions can help discourage students from binge drinking when they reach legal age.

The University of Michigan study will be published in the Journal of Consulting and Clinical Psychology.