Beer appears to make people less shy about sex - especially women, a psychological study has shown.
Scientists found that beer drinking made it easier for volunteers to view explicit sexual images, and the effect was greater for women than for men.
However, no change was seen in levels of sexual arousal.
Another effect was a boost in positive behaviour. After downing half a litre of beer, study participants were more attracted to happy faces and social situations.
The findings go some way towards providing an explanation for "beer goggles" - a slang term used to describe how the influence of alcohol can make an unattractive person appear beautiful.
Lead researcher Professor Matthias Liechti, from Basel University Hospital in Switzerland, said: "The effect of many medications and substances of abuse have been tested on various tests of emotion processing and social cognition.
"However, although many people drink beer and know its effects through personal experience, there is surprisingly little scientific data on its effects on the processing of emotional social information.
"We found that drinking a glass of beer helps people see happy faces faster, and enhances concern for positive emotional situations.
"Alcohol also facilitates the viewing of sexual images, consistent with disinhibition, but it does not actually enhance sexual arousal.
"These effects of alcohol on social cognition likely enhance sociability."
The research was presented at the European College of Neuropsychopharmacology (ECNP) annual meeting in Vienna and also appears in the journal Psychopharmacology.
Professor Wim van den Brink, from the University of Amsterdam, former chairman of the ECNP Scientific Programme Committee, said: "This is an interesting study confirming conventional wisdom that alcohol is a social lubricant and that moderate use of alcohol makes people happier, more social and less inhibited when it comes to sexual engagement.
"The sex differences in the findings can either be explained by differences in blood alcohol concentration between males and females with the same alcohol intake, differences in tolerance due to differences in previous levels of alcohol consumption or by socio-cultural factors."
For the study, the researchers recruited 60 healthy volunteers aged 18 to 50 and gave half of them a half litre glass of alcoholic beer. The remaining participants were given non-alcoholic beer.
The volunteers were then asked to perform a range of tasks including a face recognition test, an empathy test and a sexual arousal test.
Beer drinking had no effect on levels of the hormone oxytocin, which is thought to act as a "social lubricant" and assist bonding between individuals.