If you woke up over the weekend realising you'd overdone it a little the night before, the reason might be the glass you were drinking from.
British researchers have discovered that people drink alcohol twice as quickly from a European-style curved glass than from a straight-sided one.
Dr Angela Attwood of Bristol University asked 160 social drinkers aged 18-40 to drink either lager or a non-alcoholic soft drink from either a straight-sided glass or a curved 'beer flute'.
And, she found, people supped their beer almost twice as slowly when it was presented in a straight-sided glass compared to the curved glass. There was no difference in drinking rates when the drink was non-alcoholic.
The researchers suspected the reason for this might be because it's much harder to judge the halfway point of shaped glasses, meaning drinkers can't tell how much they've had.
In order to test this, the team gave participants a series of pictures of the two glasses holding different amounts of liquid, and asked them to gauge whether they were more or less than half-full.
And not only did people find it harder to tell with the curved glass, the people who were most inaccurate were also the ones who changed their drinking speed the most.
"While many people drink alcohol responsibly, it is not difficult to have 'one too many' and become intoxicated. Because of the negative effects alcohol has on decision making and control of behaviour, this opens us up to a number of risks," says Attwood.
"People often talk of 'pacing themselves' when drinking alcohol as a means of controlling levels of drunkenness, and I think the important point to take from our research is that the ability to pace effectively may be compromised when drinking from certain types of glasses."