New research has found no compelling evidence that more physically attractive young adult women have higher levels of the sex hormones estradiol and progesterone. The study, which appears in the journal Psychoneuroendocrinology, is a major blow to a popular theory in evolutionary psychology.

“Over the last few decades, there has been an enormous amount of work done on trying to understand why people find certain types of faces or certain body shapes particularly attractive,” said study author Benedict Jones (@ben_c_j) of the University of Glasgow and the Face Research Lab.

“One influential theory is that attractive women’s faces and body shapes are indicators of their hormone levels. The idea being that women with certain hormonal profiles (relatively high levels of estradiol and progesterone) are less likely to have problems conceiving and would therefore make good mates.”

“Although this controversial idea is a fundamental assumption of much of the work on human mate preferences, the evidence for it didn’t seem very convincing to us and was based on a handful of small studies that generally had very small sample sizes. So, we tried to replicate these assumed links between hormone levels and facial attractiveness and between hormone levels and body shape in a much larger sample,” Jones explained.

In the study, 249 female college students (average age 21) provided the researchers with saliva samples and standardized facial photographs. The saliva samples were used to measure their hormone levels, while a separate group of individuals rated the attractiveness of the photographs. The researchers also measured the waist-to-hip ratio of the women.

But the researchers failed to find evidence that higher estradiol and progesterone levels were associated with higher attractiveness ratings or lower waist-to-hip ratios. In fact, higher estradiol levels were associated with higher waist-to-hip ratios — the opposite of what the theory predicts.

Women with lower waist-to-hip ratios did tend to have higher levels of progesterone, but the relationship was weak.

The findings challenge “the assumption that women’s attractiveness is closely linked to their hormone levels,” Jones said.

“Although our data challenge this influential idea, we still don’t understand why some faces are judged more attractive than others. Some of our ongoing work hints that, rather than reflecting a person’s underlying physical qualities, attractiveness might be better understood as a byproduct of how easily we can process faces,” Jones explained.

The study, “No compelling evidence that more physically attractive young adult women have higher estradiol or progesterone“, was authored by Benedict C. Jones,, Amanda C. Hahn, Claire I. Fisher, Hongyi Wang, Michal Kandrik, Junpeng Lao, Chengyang Han, Anthony J. Lee, Iris J. Holzleitner, and Lisa M. DeBruine.

