Attractive staff at shops could potentially discourage female customers who may perceive them as “direct social threats”, according to a study.

Researchers in Australia analysed the behaviour of female shoppers aged between 18 and 26 when dealing with attractive or unattractive members of staff.

They found that women were less likely to buy an item if they thought the shop assistant was better looking than them, regardless of whether or not the product was related to appearance.

Bianca Price, of the University of South Australia, said it was primarily because women are “biologically competitive” and the perception that another female is a direct social threat affects their behaviour.

Price added: “Retailers often think that beautiful is better. In the same way they use a celebrity to endorse a product, they hire a beautiful girl thinking that it reflects the brand and that other women will want to be like her.

“It does not always work like that - women may not consider celebrities a direct social threat, but they might consider the girl at their local shopping centre to be one.”

The key for retailers, Price said, was to hire “women of all shapes and sizes - someone for each of your potential customers to relate to”.

Price’s findings were published recently in the Journal of International Business and Economics.