What Is Iridology? Proponents of iridology claim that information about the patient’s overall health—including healthy or unhealthy organs, past andfuture health issues, and susceptibility to certain illnesses/diseases—can be gleaned from the study of the patterns, colors, and other characteristics of the patient’s iris.Flashlights, magnifying glasses, cameras, and slit-lamp microscopes are used to examine the patient’s irises. Iridologists look for tissue …