Customers of bars that play loud music drink more quickly and in fewer gulps, French researchers said on Friday.
Their study, published in the journal Alcoholism: Clinical & Experimental Research, found that turning up the music spurred drinkers to down a glass of beer about three minutes more quickly.
To gauge the effect of sound levels on drinking, the team spent three Saturday nights visiting two bars, where they observed 40 men aged between 18 and 25 drinking beer.
"We have shown that environmental music played in a bar is associated with an increase in drinking," Nicolas Gueguen, a behavioural sciences researcher at the University of Southern Brittany in France, who led the study, said in a statement.
With help from the bars' owners, the team turned the music up and down and then recorded how much and how fast people drank. The men did not know they were being observed.
Louder music spurred more consumption, with the average number of drinks ordered by patrons rising to 3.4 drinks from 2.6 drinks, Gueguen found. The time taken to drink a beer fell to an average 11.45 minutes from 14.51 minutes.
The researchers acknowledged some limitations to their study, for example that the experiment was on a small scale and could not be applied to every bar.
They said it was not clear why louder music appeared to increase alcohol consumption but said it might make conversation more difficult, forcing people to drink more and talk less.