A Brief History of Iridology

It has long been said that “eyes are the windows to the soul”; iridologists claim that eyes are window’s into the human body’s state of health. Also referred to as “iridodiagnosis” or “iridiagnosis”, iridology is a form of “alternative medicine” introduced in the 17th century CE and still occasionally practiced today, despite being debunked as pseudoscience literally hundreds of years ago.

What Is Iridology?

Proponents of iridology claim that information about the patient’s overall health—including healthy or unhealthy organs, past and future 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.

As you can plainly see, this patient's got the leprosy.

As you can plainly see, this patient gots the leprosy.

Flashlights, magnifying glasses, cameras, and slit-lamp microscopes are used to examine the patient’s irises. Iridologists look for tissue changes, specific pigment patterns, irregular stromal architecture (the stroma is the outermost layer of the iris), and more. Charts dividing the iris into 80-90 sections, each corresponding to a bodily system, are used to determine whether the system indicated by a given iris section is healthy, inflamed, or distressed. According to iridologists, changes to specific details of the iris correspond to changes in internal organs.

However, as the features of the iris are among the most stable parts of the human body from birth to death, and as quality research studies and supportive clinical data on iridology are wholly nonexistent, the practice has long been considered pseudoscience. Iridology is and never has been regulated or licensed by any American governmental agency, and—somehow—numerous organizations offering certification in the practice still exist today.

Who’s the Jokester Behind This One?

Though not referred to as “iridology” in the text, a number of the general principles of iridology are laid out in Chiromatica Medica, written by Philip Meyen von Coburg and first published in 1665.

The first to use the term “iridology” was Hungarian scientist and physician Ignaz von Peczely, now considered the “Father of Iridology”. (In von Peczely’s native tongue, the word is augendiagnostik, literally “eye diagnosis”.) Legend has it that von Peczely “discovered” iridology when he noticed similar markings in the irises of a man and an owl who had both broken a leg.

The practice was furthered by Swedish doctor/priest Nils Liljequist. Suffering from unnatural outgrowth of his lymph nodes, Liljequist treated the ailment with medication made of iodine and quinine (and hopefully other stuff, too, but no exact record exists). After treatment, he noticed changes to the color of his irises, which inspired him to create and publish an iridology “atlas” in 1893. This atlas, The Diagnosis of the Eye, contained 270 illustrations of the iris.

It was not until the 1950s that iridology came to the United States. Bernard Jensen, a chiropractor (who better to study the eye, amirite?), offered classes in iridology, based on his own methods. In 1979, Jensen and his partners in quackery, P. Johannes Thiel and Edward Lane, failed to establish the basis of their practice during a controlled experiment. In the experiment, Jensen et al. were tasked with analyzing photos of 143 different irises to identify patients with kidney disease (48 of those studied suffered from kidney ailments). The iridologists, perhaps unsurprisingly, could not determine the healthy from the unhealthy; one of the “scientists” deduced that 88 percent of the healthy patients suffered from kidney disease, another determined that 74 percent of the actually ailing patients were, in fact, healthy.

Photo credit: Joe Crawford (artlung) via Foter.com / CC BY