Key PointsQuestionAre there associations between retina-related biological changes and mortality and morbidity of common diseases?FindingsIn this cohort study of health information from 93 838 adults in the United Kingdom verified with data from 592 Chinese patients, retinal ganglion cell–inner plexiform layer thickness metabolic profile was associated with mortality and morbidity of 6 common diseases. These profiles improved estimates that incorporated clinical indicators only.MeaningThese results suggest that retinal ganglion cell–inner plexiform layer thickness metabolic profiles may inform mortality and common disease risks, providing a distinctive insight into the retina as a window to systemic health.