Study finds most attractive eyelash length is about one‑third of the eye width

A new study suggests that eyelashes about one‑third the width of the eye are judged most attractive and healthiest, and that very long lashes may signal greater sexual receptivity rather than greater overall appeal.

Researchers at the University of Plymouth asked 120 participants in the United Kingdom to rate computer‑generated images of female faces that represented a range of ethnicities and included 11 variations in eyelash length. Ratings for perceived health and attractiveness followed an inverted‑U pattern, peaking when eyelash length was roughly one‑third the eye’s width; ratings dropped for both very short and very long lashes. Longer eyelashes, by contrast, were associated with higher ratings of sexual receptivity.

The study, led by Farid Pazhoohi and published in the journal Archives of Sexual Behaviour, reported that “results showed that eyelash length is positively associated with perceived sexual receptivity, suggesting that longer eyelashes might signal openness to casual relationships, despite lower attractiveness and health ratings.” The authors wrote that eyelashes may serve as health indicators because “various diseases can influence eyelash length.”

Pazhoohi and colleagues used synthetic facial images to control for other factors while varying lash length, and asked participants to rate how healthy, attractive and sexually receptive each face appeared. Their analysis identified an optimal-length region for attractiveness and health that corresponds with prior biological research.

A 2015 study from the Georgia Institute of Technology found feathers or hairs around the eyes in 22 mammal species—humans among them—tended to measure about one‑third of the eye’s width. That research used anatomical measurements and wind‑tunnel experiments and concluded the length is effective at diverting airflow and dust, helping to keep the eye moist and protected. The new human perception study cites those functional findings to suggest an evolutionary basis for why moderate eyelash length is preferred.

The University of Plymouth team noted reasons why very short or very long lashes may fare worse in attractiveness ratings. Short lashes can be associated with aging or poor health, while extremely long or evidently artificial lashes can appear exaggerated and less natural, diminishing perceived attractiveness. Moderate lashes may enhance the eye’s appearance without seeming fake.

The paper’s findings intersect with conversations in cosmetic culture about false eyelashes and extensions. The authors wrote that perceptions of attractiveness and sexual receptivity can diverge, indicating that cosmetic practices that lengthen lashes considerably might change the social signal a wearer sends without increasing general attractiveness.

The study adds to a stream of recent research into facial features and perceived attractiveness. Earlier work by the same author and by other groups has examined features such as eyebrow shape and arch, finding preferences for natural shapes with a slight arch over more extreme styles.

The research is limited by its use of simulated images and a modest sample drawn from the United Kingdom; the authors recommended further work with larger, more diverse samples and with real faces to test whether the same preference patterns hold across cultures. The study’s publication in Archives of Sexual Behaviour provides a peer‑reviewed account of the experiment and its conclusions, but does not prescribe individual fashion or grooming choices. Instead, it links perceptual judgments about eyelashes to functional biological evidence and to social impressions of health, attractiveness and sexual receptivity.