Before you down that pint, check the shape of your glass--you might be drinking more beer than you realize. According to a 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.

Angela Attwood of the University of Bristol and her team divided 160 young, healthy people -- students and faculty members and members of the general public -- into eight groups. They found that one group consistently drank much faster than the others: the group drinking a full glass of lager out of curved flute glasses. In a paper published in PLoS ONE, the team reports that whereas the group with straight glasses nursed their 12-ounce lager for about 13 minutes, the group with the same amount of beer served in curved glasses finished in less than 8 minutes, drinking alcohol almost as quickly as the soda-drinkers guzzled their pop. However, the researchers observed no differences between people drinking 6 ounces of beer out of straight vs. fluted glasses.

Attwood believes that the reason for the increase in speed is that the halfway point in a curved glass is ambiguous. Social beer drinkers, she says, naturally tend to pace themselves when drinking alcohol, judging their speed by how fast they reach half-full. A simple solution to this problem would be to mark beer glasses with the accurate halfway point, she says. "We can't tell people not to drink, but we can give them a little more control."



A change in fast-food restaurant ambience can affect the amount of food customers eat, an unusual study has found.

Researchers decorated a section of a Hardee's in Champaign, Ill., with indirect lighting, soft music, white tablecloths and candles. The room was soundproofed, isolated from the loud music and bright lights of the adjoining standard interior. Only one thing remained the same: the menu.

As customers arrived, they were randomly assigned to one room or the other. The study, published in the journal Psychological Reports, found that food selection did not differ between groups. But the fine diners spent an average of 4.7 percent more time eating, and ate less of what they ordered -- 86 percent of the food on their plates, compared with 95 percent for those in the regular area.

The fine diners consumed an average of 775.3 calories, while the others ate 949.2. Yet on questionnaires, the fine diners rated the food more highly.

"You create a nice atmosphere, people talk more, they concentrate less on the food," said an author of the study, Koert van Ittersum, an associate professor of marketing at the Georgia Institute of Technology. "And they leave the place more satisfied."