Before you down that pint, check the shape of your glass -- you might be drinking more beer than you realize. According to a new study of British beer drinkers, an optical illusion caused by the shape of a curved glass can dramatically increase the speed at which we swill.
Binge drinking is a growing problem in the United Kingdom, particularly among young people, says experimental psychologist Angela Attwood of the University of Bristol. The rise in drinking and associated criminal activity is so severe, she says, that "people are getting more and more reluctant to venture into city centers at night." Aside from increases in crime, binge drinking is a public health risk: according to the World Health Organization (WHO), the harmful use of alcohol -- defined as drinking that damages health and has negative social repercussions -- results in 2.5 million deaths per year worldwide and is the third largest factor in the global burden of disease. Although WHO describes legislative solutions such as raising the price of alcohol and increasing the drinking age as effective interventions, such measures are so unpopular that many governments are reluctant to implement them.
Given the difficulty of controlling drinking with legislation, Attwood and her colleagues hope to curb it through education. People don't always realize how much or how fast they're drinking, she explains. For example, a previous study by a team of researchers at Queen Margaret University in the United Kingdom found that the mean alcohol content in a "usual" single drink poured by subjects was actually twice that of the standard U.K. alcohol "unit" used to measure consumption. Attwood suspected that the shape of a beer glass, which can give the appearance of different volumes to the same amount of liquid, might also distort perception of how much alcohol is being consumed.