As a facial plastic surgeon, I am in the business of beauty. On a daily basis, I am therefore confronted by the question, “what is beauty?” and specifically, “what makes a face beautiful?”

We, as philosophers, scientists, artists, and people, have been challenged by this question since the beginning of time. A commonly held belief is that “beauty is in the eye of the beholder.” Although culture certainly contributes to what we find beautiful, evidence suggests that the perception of beauty is not only innate, but also universal. People across ethnicities and heritages generally agree on which faces are attractive. Preferences for facial attractiveness also emerge early in development before cultural standards of beauty are likely assimilated: infants as young as three months of age display a robust preference for attractive faces versus less attractive faces. Beauty, it appears, is not just a social construct.

So why do we have the preferences that we do? Recent studies propose that the key to understanding beauty is in our biology; our standards for beauty are evolutionarily and biologically based adaptations for ensuring reproductive success, i.e., for finding good mates. Although this viewpoint certainly cannot explain everything, there are four concepts of facial beauty that have been shown to be timeless and cross-cultural: symmetry, averageness, sexual dimorphism, and youth.

The concept of symmetry seems fairly intuitive. Studies show that symmetric faces are viewed as more attractive than asymmetric ones, and the more symmetric a face is, the more attractive it appears. Averageness and beauty, however, initially seem to be mutually exclusive concepts. In a landmark study, Langlois and colleagues (Psychol Sci 1990) demonstrated that a composite of faces, mathematically averaged from many individual faces, was found to be more attractive than the faces used to generate it. And the more faces used to construct the composite, the more attractive it was deemed. Although counterintuitive, averageness is attractive (confirmed in many follow-up studies). Theorists propose that this may be so because average traits reflect developmental stability, disease resistance, and good health (extreme and uncommon features are frequently due to disadvantageous mutations)—and are therefore associated with a genetic and reproductive advantage. However, not all attractive faces are just average and not all average faces are optimally attractive. There’s more to it.

Sexual dimorphism is the phenotypic (external appearance) difference between males and females. Male and female faces diverge at puberty due to the influences of testosterone and estrogen, respectively. Features such as high cheekbones, large eyes, smaller noses, fuller lips, and thinner jaws exaggerate the ways in which the adult female differs from the adult male. These highly feminine features have been shown to be strongly attractive in female faces (preferred over averageness) and are said to be signals of high fertility and mate quality. The last concept of beauty is youth. Youthful faces are deemed to be more attractive than older faces, and this has been found true across a range of cultures. As female faces age, they become more masculine in appearance. Therefore, femininity, fertility, as well as attractiveness all decline with age.

Our desire for beauty is hardwired in our brains.

Although societal pressures certainly play a role, we are inherently motivated to be the best, most feminine, and youthful version of ourselves. Fitness, diet, clothing, makeup and cosmetic surgery are all tools that women (and men) use to cultivate their outer and inner beauty. The reality is, beauty is not inconsequential. Research shows that in today’s world, increased beauty confers advantages socially and professionally. Our appearance represents our most public self and seeking beauty is a natural pursuit for all of us.

However, beauty is not about being perfect. It is about putting your best face forward, and this starts from within. The most beautiful reflection of oneself is achieved when health, strength, intelligence, and confidence is achieved on the inside.

An interesting podcast on the topic:
TED Talk: “What is Beauty?” – TED speakers suggest reasons why humans are hardwired to crave and respond to beauty. (Original broadcast date: 04.19.2013; Released on iTunes: 01.01.2016)

By Leslie Kim, M.D., M.P.H. - Co-Founder and Facial Plastic Surgeon