Pretty women tend to be 'less stressed and more fertile', say scientists who say beauty isn't just skin deep



Attractive women have less of the hormone cortisol, associated with stress

Stress can also adversely effect fertility - so 'facial attractiveness signals reproductive potential,' say the researchers

But unlike men - where attractiveness is linked to a strong immune system - this may not be the case for women



Attractive women are more than just a pretty face - they also have less of the hormone cortisol, which is associated with stress, a study shows.

Researchers point out that stress can also adversely effect fertility, and suggest one explanation may be that 'facial attractiveness signals reproductive potential'.

Attractive women also carry just the right amount of fat in their bodies - not too much and not too little, according to the research.

But, contrary to recent research in men, a strong immune system may not be associated with being beautiful.

Attractive women, such as former model and mother-of-four Jools Oliver (with children Poppy Honey, Daisy Boo, Petal Blossom, Buddy Bear and husband Jamie) may also be more fertile, say scientists

A study of Latvian women found links between facial attractiveness and their amount of cortisol and fat, but not responsiveness to infection.

Sometimes described as our 'life-sustaining hormone', cortisol is produced in the adrenal glands and is responsible for metabolism, energy levels, blood pressure and combating illness.

It is especially important at times when the body experiences intense stress such as surgery, trauma or serious infection.

To test the immunity of good looking women, researchers photographed a selection of participants, vaccinated them against hepatitis B and measured the amount of antibodies produced.

Surprisingly, immune function did not predict facial attractiveness. Instead, those with lower cortisol levels in the blood tended to be more beautiful, suggesting stressed women are plainer.

Also having high or low amounts of fat reduced allure, showing being too slim can be as big a turn off as carrying to many pounds.

Recent research has suggested that facial attractiveness indicates immune responsiveness in men - but being pretty doesn't necessary mean a woman has a strong immune system



Dr Markus Rantala, whose findings are published in the Royal Society journal Biology Letters, said: 'Interestingly, facial attractiveness correlated negatively with plasma cortisol level suggesting stress reduces attractiveness in women.

'This supports previous findings from male faces, which show cortisol is inversely related to facial attractiveness.

'This has been interpreted as a mediator of condition dependent cues in the face (e.g. to health) or as a signal of the ability to cope with stressors.

'Perhaps, then, low levels of cortisol also signal health in female faces. This would be consistent with many studies in humans that have found stress has strong negative effect on health, including immune function, heart disease and susceptibility to cancer, etc.

Research is beginning to uncover that beauty really is connected to reproductive health and fertility. The model Heidi Klum has four children

'An alternative explanation is facial attractiveness signals reproductive potential, which is mediated partly by stress hormones, because many studies have demonstrated stress disturbs fertility.'

For decades, scientists believed when men gaze at women they are merely using facial clues such as large eyes, a small nose and full lips to check their prospective mate has high 'fitness' and can efficiently pass their genes to the next generation.



But research is beginning to uncover that beauty really is not just skin deep and is connected to reproductive health and fertility.

Earlier, the same team found men who were best at producing antibodies in response to a hepatitus B jab were considered better looking by women.

In the latest study Dr Rantala, of the University of Turku, Finland, and colleagues photographed 52 young women with an average age of 20 and asked 18 heterosexual male undergraduates to rate their attractiveness.

Dr Rantala said: 'In contrast to findings in men, we found women's immune response is not associated with their facial attractiveness.'

But because the system is so complex it would be premature to say a pretty face does not signal a strong immune defence in women, because there may be different trade offs in components going on.

Dr Rantala said: 'It is possible facial attractiveness signals a different arm of the immune defence in women than men. This remains to be tested in future studies.'

He added: 'Our study suggests facial attractiveness in women does not indicate immune responsiveness against hepatitis B but is associated with two other aspects of long term health and fertility, circulating levels of the stress hormone cortisol and percentage body fat.'

Ironically, a study by Spanish researchers published three years ago found being in the company of a beautiful woman can be bad for men's health - by increasing their cortisol.

just five minutes alone with her raised amounts of the hormone, too much of which can cause heart disease. The effect was worst in those who believed she was 'out of their league'.



