This passage explains the history and theory of iridology.

Lexile Level: 1040L

Categories: Sports & Health Science & Technology

There's an old saying that the eyes are a window to the soul. Some scientists believe that eyes are also a window into one's health. Iridologists look closely at people's irises, the colored parts of your eyes, to see if you are susceptible to various illnesses and diseases. They believe that as conditions change inside your body, such as at the beginning of a serious illness like diabetes or cancer, the lines and markings of your iris change. The color of your eyes can even change. This isn't a new science. The earliest writings on iridology date back to the 1600s, but the subject didn't become widely investigated by doctors until the 19th century. A Hungarian scientist accidentally broke an owl's leg and noticed that black lines quickly appeared in the owl's eyes. The scientist later observed that humans had similar lines in their irises after they had suffered broken or fractured bones. Still, many doctors today do not believe iridology is a valid science.


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