Fashions in female beauty come and go, but the desirability of a slim waist remains a constant, a study suggests.

Rosebud lips and milky complexions have had their day as ideals of beauty, while the high cheekbones prized in women today were considered ugly in the Victorian era.

Plumpness was a sought- after attribute in the 17th and 18th centuries, but the slimmer figure has taken over.

Discernible waists, however, are the one feature of the female form that has always been in demand, according to academics who analysed references to beauty in literature.

Waistlines, they said, were an easily recognised sign of fertility and health, and men evolved to associate narrowness with desirability.

Fertility is indicated because a narrow waist is linked to higher oestrogen levels. After puberty, a girl’s waist narrows in proportion to her hips as oestrogen levels rise, and then expands as the hormone concentration decreases with age.

Obesity is linked to lower oestrogen levels and an increased risk of disease.

The researchers assessed the constants of female beauty by analysing references in 345,000 works of fiction, prose and drama, mostly from the 16th to the 18th centuries. Most of the literature was British and American, but a small selection of Indian and Chinese romantic and erotic poetry from the 1st to the 6th centuries was also analysed.

Waists were by far the most admired of eight physical features, followed by breasts, legs, thighs and plumpness.

Hips, buttocks and slimness were the least mentioned, said the study, published in the Proceedings of the Royal Society.

Breasts were regarded as the feature most connected with romance, or perhaps eroticism, but there was a lack of unanimity about what shape they should take. Some said small, others big and still more defined them as best rounded.

The researchers said: “References to beautiful women abound throughout human history and across cultures.

“Ancient Greek epics, Persian and Chinese poetry, Indian classics, mythology and even popular or folk stories glorify feminine beauty . . . our study suggests that, in spite of variation in the description of beauty, the marker of health and fertility — a small waist — has always been an invariant symbol of feminine beauty.”

Devandra Singh, of the University of Texas at Austin, led the study.

Waxing lyrical

"My love is unique; no one can rival her, for she is the most beautiful woman alive . . . Gold is nothing compared to her arms, and her fingers are like the lotus flowers. Her buttocks are full, but her waist is narrow. Just by passing, she has stolen away my heart"

Rameses the Great to Queen Nefertari (c 1300-1250BC) written on her tomb

"Her skin and teeth must be cleare, bright and neat . . . / Large brests, large hips, large space betweene the browes / A narrow mouth, small waste"

Sir John Harington (1561-1612)

"Beautiful women . . . in the palace of Chu, there were none who did not admire their slender waist"

Xu Ling (507-83)

"That which her slender waist confined Shall now my joyful temples bind; No monarch but would give his crown His arms might do what this has done”

Edmund Waller On: a Girdle

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