There’s no denying it, some people just have ‘it’. There is something about them that is inarguably, yet inexplicably, attractive.

Research continually shows there are biological and evolutionary triggers that determine whether we are attracted to someone, and why. Symmetry definitely has something to do with it, with lopsidedness thought to reflect poor health and bad genes. Some other interesting findings include:

Blonde vs brunette

It’s an age-old debate that had even Charles Darwin stumped – he couldn’t find any acceptable reason men might prefer blondes. Since Darwin’s time, however, there have been a few advancements in the science behind hair preference.

Blonde hair is thought to be an indicator of youth and sexual vitality, but a recent study, which attempted to determine the most beautiful woman in the world, picked a brunette, and a 2011 study in the Scandinavian Journal of Psychology found brunettes are generally considered more attractive.

Waist to hip ratio

This measurement is calculated subconsciously, with men preferring a waist-to-hip ratio
of 7:10 in women, and women preferring a ratio of 9:10 in men.

A BMI of 20.85 has been shown as the most attractive weight for a woman, with Scarlett Johansson’s body voted the most attractive female figure.

It’s in the eyes

You may not know what a limbal ring is, but you’ll certainly notice it when you see an attractive one. This ring is where the iris meets the white of the eye and a dark limbal ring is thought to single youth, health and attractiveness.

Smile (but only if you’re female)

Research has found that smiling women are deemed more attractive, whereas men showing happy emotions are considered less attractive.