Study will compare facial aging in identical twins using 3D face images

Identical twins share the same genes, which makes them a powerful way to study how lifestyle and environment - rather than genetics - affect how faces age. This study builds on a landmark 2009 twin study by using modern three-dimensional (3D) facial imaging, which measures facial shape and volume precisely instead of relying on regular photographs. The study will also look at whether use of GLP-1 weight-loss medications (such as semaglutide or tirzepatide), sometimes associated with facial changes informally called "Ozempic face," is related to measurable differences in facial aging.

The study will enroll adult identical twin pairs attending the Twins Days Festival in Twinsburg, Ohio, in August 2026. Participation takes about 30 minutes and happens in a single visit at the festival study booth. Each twin will complete a questionnaire about lifestyle, environment, and medical history (such as sun exposure, smoking, sleep, and medication use) and have a 3D image of their face taken with a non-contact camera system. There is no treatment, no medication, no blood draw or biological sample, and no follow-up visit. Researchers will then compare facial measurements within each twin pair to learn which lifestyle and environmental factors are linked to visible facial aging.