Compared to the standard size of a drink defined by a national survey,
students over-poured shots by 26 percent, mixed drinks by 80 percent and
beer by 25 percent, say Aaron White, Ph.D., of Duke University Medical
Center and colleagues. Their findings appear in the November issue of Alcoholism:
Clinical and Experimental Research.
And the larger the cup, the higher its tendency to runneth over: The amount
of alcohol poured by the students increased with the size of the cups they
were given, the researchers found.
White and colleagues conclude that a student’s idea
of a single drink is much different from the amount that researchers
use in their
studies of college drinking.
“For instance, students drinking from a keg might consider each
cup full of beer, regardless of its size, to constitute one drink rather
than the 12-ounce serving size specified in many surveys,” White
says.
Since most of the data on college drinking come from the students themselves,
the new findings may throw doubt on previous estimates of campus alcohol
use and abuse. This may be especially true because almost half of the drinks
consumed by the students in the two weeks before the study were freely
poured, not bottled in discrete amounts or poured by trained bartenders,
according to White.
“A student who indicates having consumed five drinks in one night
might actually have had 10 or more standard drinks if the drinks were free-poured,” he
says.
The study included 106 undergraduates ages 18 and older at Duke University
in Durham, N.C. After answering a survey about their drinking habits, the
students poured water into cups in amounts that they thought were equivalent
to one beer, one shot or the amount of alcohol in one mixed drink.
The researchers then compared the students’ single-drink
volumes to national survey standards, which are 12 ounces for one beer
and 1.25
ounces of liquor for a shot or mixed drink.
While students consistently poured more than the standard amounts, those
who said that they had drunk a lot of shots or mixed drinks in the two
weeks prior to the study had a more steady hand, pouring drinks that were
closer to the standard amount.
“The fact that both volumes and concentrations of drinks can vary
widely makes it difficult to provide the public with simple definitions
of drinks that make sense in the real world,” White and colleagues
conclude.
Labeling alcoholic beverages with serving size information — a practice
that has taken hold in Australia and other countries — may help
clear up some of the confusion and make people aware of their true drinking
levels,
the researchers say.
