A new study published in Aesthetic Surgery Journal has shown that use of contact lenses could lead to eyelid droopiness.

Researchers reviewed photographs of 96 sets of identical twins who met in Twinsburg, Ohio, on a yearly basis from 2008 to 2010, measuring the level of eyelid droopiness or ptosis in each.

9 different environmental factors were considered as a potential cause for ptosis which were evaluated through an extensive questionnaire and special standardised photography.

According to the data collected, wearing either hard or soft contact lenses was associated with ptosis.

The average difference in eyelid droopiness between twins was 0.5 millimetres. Among twins who didn’t wear contacts, ptosis was around 1.0 millimetre.

In twins who wore soft contacts, that number increased to 1.41 millimetres, rising further to 1.84 millimetres for those who sported hard contacts.

Researchers also looked for links between ptosis and BMI, smoking, sun exposure, alcohol consumption, work-related stress, and sleep, none of which had a statistically significant impact on eyelid droopiness.

Speaking on the findings, study author Dr Bahman Guyurona who is a facial plastic surgeon told Yahoo Health,

“Since the identical twins are genetically destined to have similar facial and eyelid features, if there is a difference, it is primarily related to the environmental factors, we were able to demonstrate that, of the external factors unrelated to the genes or ageing, use of contacts was the only factor that linked to the droopy eyelids.”

Check out photos illustrating the study above.