Determinants of female physical attractiveness

Features such as a symmetrical face, large breasts, and low waist-hip ratio are commonly considered physically attractive in females, because they are thought to indicate physical health and high fertility to a potential mate. The determinants of female physical attractiveness include those aspects that display health and fitness for reproduction and sustenance. These include correlates of fertility such as youth, waist-hip ratio, breast size, breast symmetry, body mass proportion and facial symmetry. Though it has been said that facial attractiveness and symmetry signal good health, it has been questioned and said not to be highly related to good health.

Facial alignment

In a study by University of Louisville psychologist Michael Cunningham, dimensions and proportions of what was regarded as attractive emerged with remarkable consistency. The ideal attractive female face featured "eye width that is three-tenths the width of the face at the eyes' level; chin length, one-fifth the height of the face; distance from the center of the eye to the bottom of the eyebrow, one-tenth the height of the face; the height of the visible eyeball, one-fourteenth the height of the face; the width of the pupil, one-fourteenth the distance between the cheekbones; and the total area for the nose, less than 5 percent of the area of the face." Very small differences mattered; for example, "the ideal mouth was half or 50 percent the width of the face at mouth level; if that percentage varied "by as little at 10 points," the face was rated as less attractive. The study found the "beauty of the female face ... is mathematically quantifiable.

Desired traits were large female eyes, small chin and nose, and these "infantlike features draw out in them the same caretaking response a baby would–they make a woman seem cute and adorable."[38] Further, high wide cheekbones and narrow cheeks are "signs that a woman has reached puberty" and "high eyebrows, dilated pupils and wide smile" signal excitement and sociability. One psychologist speculated there were two opposing principles of female beauty: prettiness and rarity. So average, symmetrical features is one ideal, while unusual, stand-out features is another. A study performed by the University of Toronto found that the most attractive facial dimensions were those found in the average female face. However, the study looked only at white women.

Signals of youth

Because female fecundity typically declines after the late twenties, youth is an important aspect of physical attractiveness. One study across 37 cultures showed men desire, on average, a woman 2.5 years younger than themselves for a wife, with men in Nigeria and Zambia at the far extreme, desiring their wives to be 6.5 to 7.5 years younger. As men age, they also desire a larger age gap from their mates. The reasons for this preference are currently debated.

This preference for youth has also led to a preference of neotenic and youthful-appearing features. High, firm breasts,fair or long and lustrous hair (or a combination of the three), full red lips, clear smooth skin, and clear eyes, are viewed as attractive in women.

Breast size

Full breasts may be attractive to some men in Western societies, as opposed to non-Western societies that tend not to favour women with hourglass figures, because women with higher breast to under-breast ratios typically have higher levels of the sex hormone, estradiol, which promotes fertility.[50] Larger breasts also display the aging process more noticeably, hence they are a relatively reliable indicator of long-term fertility.