Beer taste excites male brain
Just a tiny taste of your favourite tipple can excite the brain and increase the urge to drink, even without any effect of alcohol - according to a study on 49 men.
The taste triggered the release of the brain's reward chemical, dopamine.
The results of the study, published in the journal Neuropsychopharmacology, showed a greater effect in people with a family history of alcoholism.
Experts said the family link was "surprising".
The men were placed in a brain scanner while small amounts of different drinks were sprayed into their mouths.
Researchers at the Indiana University School of Medicine, in the US, compared the effects of spraying water, a sports drinks and the participant's favourite beer.
Each was given 15ml of fluid over 15 minutes. It is enough to make a pint go round 38 people, so the scientists said the alcohol in the beer would have no effect on the body.
The results showed that more dopamine was released in the brain after beer and the men were more likely to say they wanted to have an alcoholic drink.
Prof David Kareken said: "We believe this is the first experiment in humans to show that the taste of an alcoholic drink alone, without any intoxicating effect from the alcohol, can elicit this dopamine activity in the brain's reward centres."
He suggested the more pronounced effect in men with a family history of alcoholism could be an inherited risk factor for alcoholism.
Prof Dai Stephens, from the University of Sussex, said: "These findings, though neatly done, and a first convincing demonstration in humans that a drink's flavour has such effects on the brain, are not particularly surprising as we have known for some time from animal studies that events conditioned to drug taking come to increase dopamine."
However, he said the family effect was surprising and raised questions about whether this "underlies the development of alcohol, and perhaps other drug abuse".
Peter Anderson, a professor of substance use, policy and practice at Newcastle University, said: "It is well known that all sorts of cues, including taste, smell, images, and habits raise desire for drinking.
"This paper demonstrates that taste alone impacts on the brain functions associated with desire. This is not surprising - if taste increases desire, it has to impact on brain functions."