Mirand Kerr for Reebok Reebok Forget the size zero supermodels - bigger girls can mean bigger profits say researchers from Warwick Business School.

Bad news for big fashion brands today as a new study reveals that adverts which predominantly feature less-than-buxom beauties like Victoria’s Secret model Miranda Kerr and Irina Shayk are actually more likely to discourage a sale as they make women feel bad about themselves.

Researcher Dr Tamara Ansons from the Warwick Business School said: "Attractive female models and celebrities are routinely used in advertisements and yet previous research has shown mixed reactions.”

To get to the bottom of this theory, studies were carried out in which women were shown a variety of different adverts. Some featured an attractive model on the opposite page to the product, some depicted the model next to the product, and some incorporated no attractive model at all.

The women who saw the advert with the model on the opposite page - therefore being exposing to the idealized image subtly - received the most positive response.

“We found that the way the picture of the perfectly shaped model was used was very important in determining a positive or negative effect on women’s self-perception,” Ansons told the Daily Mail.

It is believed that subtle exposure leads to a subconscious process of upward social comparison, naturally leading to negative self-deception but a more positive attitude towards the brand.

By contrast, when the exposure of a Kerr-alike is blatant, the women become conscious of the process and spark a defensive coping strategy to boost self-evaluation by belittling the model.

The study suggests that this can affect the advertised product through the transfer of negative evaluation from the model to the product.

However, subtle images of these scorn-inducing beauties can still boost spending. It’s simple: women loathe products next to large close-ups, and love (kind of) products next to less prominent images.

So all you Paris Fashion Week designers, perhaps don’t go clearing those waifs off the catwalk just yet.