Adolescents Drink Less Frequently Than Adults, But When They Do Drink, They Drink More Heavily Than Adults. When youth between the ages of 12 and 20 consume alcohol, they drink on average about five drinks per occasion about six times a month. This amount of alcohol puts an adolescent drinker in the binge range, which, depending on the study, is defined as "five or more drinks on one occasion" or "five or more drinks in a row for men and four or more drinks in a row for women." By comparison, adult drinkers age 26 and older consume on average two to three drinks per occasion about nine times a month.