21st Birthday Binge Drinking Extremely Common

The "21 for 21" ritual, where 21st birthday revelers attempt to down 21 alcoholic drinks, is highly prevalent among college students, according to new research. In the largest study of its kind, researchers at the University of Missouri determined that many college students drink to excess on their 21st birthdays and potentially jeopardize their health.

The study will appear in the June issue of the Journal of Consulting and Clinical Psychology, which is published by the American Psychological Association. The data were collected from a larger study where students at one university were followed for four years and asked questions about their drinking behaviors.

For this portion of the online survey, 2,518 current and former college students from one university responded to several questions. The participants had already turned 21 and were asked whether they had drunk alcohol to celebrate turning 21, and, if so, how much they had drunk and for how long. The researchers found that excessive drinking on this particular birthday was common, with more than four out of five participants reporting they had consumed some alcohol on their birthday. Of those participants, 34 percent of men and 24 percent of women reported consuming 21 drinks or more. The maximum for women was about 30 drinks, while the maximum for men was about 50 drinks.

Based on the information the participants provided, the researchers estimated the drinkers' blood alcohol content, reporting that 49 percent of men and 35 percent of women had estimated blood alcohol contents of 0.26 or higher, a level that clearly indicates severe alcohol intoxication and could lead to dangerous health problems such as disorientation, coma and even death. To put it in context, an average size woman would have to drink anywhere between seven and nine drinks per hour to attain a BAC of 0.26, while the average man would have to drink between 10 and 12 drinks.

"This study provides the first empirical evidence that 21st birthday drinking is a pervasive custom in which binge drinking is the norm," said Patricia C. Rutledge, PhD, the study's lead author. "This research should serve as evidence that there needs to be more public education about the dangers of 21st birthday binge drinking. The risks here are not limited to those with a history of problematic drinking, and there needs to be a strategy to address a custom that can lead to alcohol poisoning and, possibly, death."