It has long been an old adage in advertising that sex and violence help sell products. But a new study has found that, not only is the maxim incorrect, it can even “backfire” because viewers are so enthralled by the racy content they forget what is being advertised.

Researchers from the American Psychological Association found that sex and violence in adverts does attract viewers’ attention, but at the expense of the product being advertised, and it is all down to evolution, they said.

Advertisers may want to re-think using such themes or even advertising during programmes and films that are notable for their graphic scenes, said Brad Bushman, professor of communication and psychology at The Ohio State University.

“We found almost no evidence that violent and sexual programmes and ads increased advertising effectiveness,” the co-author of the study, which appeared in the Psychological Bulletin journal, said.

It can even be counterproductive as “memory, attitudes and buying intentions all decrease”.

Professor Bushman and lead author Robert Lull analysed 53 studies featuring 8,489 participants carried out last year.

Mr Lull said: “It’s not that people aren’t attracted to sex and violence. On the contrary, people have been attracted since evolutionary times.

“However, it’s at the expense of surrounding content. People pay more attention to the violence and sex surrounding ads than to the products.”

The authors wanted to find out the effectiveness of such advertising on viewers remembering a brand, their feelings towards it and whether they would buy the product. Instead they found out that people remembered only the sex and violence but not what the advert was for.

“Our findings have tremendous applied significance, especially for advertisers,” Professor Bushman said.