Why it pays to have a pretty face (but not if you're a man)

Zoe Wanamaker says her unconventional looks make life "difficult to cope with". Kathy Burke admits she'll never be a leading lady because she is - in her words - "too ugly". Vanessa Feltz is convinced what's holding her back is the belief she'll always be described as "tubby, hefty, weighty".

Their anxieties, and those of many other women who see themselves as less than glamorous, are confirmed by a study which shows that plainer women tend to earn on average 10 per cent less than women who are conventionally good looking.

Of course, it's not just less glamorous actresses and entertainers who may lose out. Ann Widdecombe, the former Tory minister, may have turned blonde because her "hair was turning white", but she has long been convinced that politics is too image-obsessed. "We marginalise ... people who are plain ugly, or just a bit different. We have our values upside down," she has said.

The new research, carried out by the University of Miami, is one of the very few studies to examine the link between labour market success and physical appearance - and is thought to be the first to quantify the value of good looks.

Dr Michael French, who led the research team, said: "We found that appearance seems to have an impact on the labour market for women, but not for men.

"Significant earnings premiums for attractiveness were found for women, but not for men. Physical appearance and weight seem to matter more for women, and height more for men."

As well as uncovering a "beauty premium" for those with the right look, the researchers also identified a "plainness penalty" for women with below-average appearance. The academics asked 1,800 people to complete a confidential questionnaire on personal characteristics and their earnings over three years. All those who took part were between 18 and 64 and were healthy. Most were married, with an average age of 40 for women and 42 for men.

Each participant was asked to "rate" his or her physical appearance, taking into account factors such as height and weight, and regularity and comeliness of their facial features.

Boxes were ticked on a sliding scale from "very handsome" or "beautiful", to "very unattractive".

When physical appearance was cross-referenced with income, it was found that women who classed themselves as having "above-average appearance" had 8 per cent higher earnings than those who rated themselves "average". For men, there was no male equivalent of a "beauty premium". The results suggest that above-average appearance is worth more to a woman than education. The former adds 7 per cent to income, while the latter is worth only 5 per cent extra, the study showed.

The value of a man's wage packet, in contrast, tends to be higher if he is married.

Manchester University psychologist Professor Cary Cooper said: "It is a very interesting finding. It is a sad commentary if people get jobs or promoted to top jobs based more on their attractiveness than their education. It shouldn't be the quality you look for when you promote someone."