Beauty lies not only in the eyes of the beholder but also in how a woman’s eyes and mouth are configured, say researchers.

The distance between her eyes and between her eyes and her mouth are key factors that determine how appealing she is, according to researchers from the University of California, San Diego (UCSD), and the University of Toronto (UT).

Pamela Pallett and Stephen Link of UCSD and Kang Lee of the UT tested the existence of an ideal facial feature arrangement. They identified the optimal relation between the eyes, the mouth and the edge of the face for individual beauty.

In four separate experiments, they asked university students to make paired comparisons of attractiveness between female faces with identical facial features but different eye-mouth distances and different distances between the eyes.

“We already know that different facial features make a female face attractive — large eyes, for example, or full lips,” said Lee, professor at UT. “Our finding also explains why sometimes an attractive person looks unattractive or vice versa after a haircut, because hairdos change the ratios.”

The researchers stumbled on two “golden ratios”, one for length and one for width. Female faces were judged more attractive when the vertical space between their eyes and mouth was about 36 percent of facial length, and the horizontal space between their eyes was about 46 percent of facial width. Interestingly, these proportions correspond with those of an average face.

“People have tried and failed to find these ratios since antiquity. The ancient Greeks found what they believed was a ‘golden ratio’ — also known as ‘phi’ or the ‘divine proportion’ — and used it in their architecture and art,” said Pallet.

“Some even suggest that Leonardo Da Vinci used the golden ratio when painting his ‘Mona Lisa.’ But there was never any proof that the golden ratio was special. As it turns out, it isn’t,” said Pallett.

“Instead of phi, we showed that average distances between the eyes, mouth and face contour form the true golden ratios,” concluded Pallett.

The authors note that only Caucasian female faces were studied. Further studies are needed to know whether there is a different set of golden ratios for male faces and for faces from other races or for children’s faces. These findings were published in Vision Research.

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