45% of students admitted drinking, and 64% of the drinkers admitted binge drinking, defined as having five or more drinks within a few hours.

 Compared to non-drinkers, teen binge drinkers were:

•  11 times more likely to ride with a driver who had been drinking alcohol in the past 30 days.
•  19 times more likely to be current smokers (smoked on one or more days in the past 30 days). 
•  Four times more likely to be in a physical fight in the past 12 months.
•  Nearly four times more likely to have ever been raped or subjected to dating violence in the past 12 months.
• Four times more likely to have attempted suicide during the past 12 months.
•  More than five times more likely to be sexually active with one or more persons during the past three months.
•  Teen binge drinkers were also more likely to use marijuana, cocaine, and inhalants, the study shows.

   Binge drinking was more commonly reported by boys than by girls, and by older teens than by younger teens.

   Binge drinkers tended to have worse grades, based on the students' self-reported grades.

   Binge Drinking Riskiest

   Student drinkers who denied binge drinking shared many of the same health risks, but to a lesser extent. 

"Our study clearly shows that it's not just that students drink alcohol, but how much they drink that most strongly affects whether they experience other health and social problems," researcher Jacqueline Miller, MD, says in a CDC news release.

 "It also underscores the importance of implementing effective strategies to prevent underage and binge drinking," Miller notes. Some students may have been reluctant to report underage drinking, so the estimates may be too low, Miller's team notes. 

More than three-quarters of seniors say they have experimented with alcohol, so the findings may not help prevent alcohol use in high school, says researcher Lori Palen of Pennsylvania State University . But such research might help identify high-risk teens before they develop a severe problem, says Zili Sloboda of the international Society for Prevention Research.

 The findings in the December issue of the journal Prevention Science raise important questions for parents. Some parents believe teen drinking is OK with adult supervision. But parents may not realize the teen brain is not fully developed and is especially vulnerable to alcohol's effects.