Controversy over Iridology – Final Degree Thesis

Translated from Spanish


There are many techniques that are known as alternative therapies and are based on natural remedies and improvements in the patient’s habits to take care of their health. Iridology, in its beginnings, was framed within these techniques but, nowadays, intelligent iris recognition systems have been developed that allow making this technique a potential extremely useful diagnostic tool. observer bias. This, combined with the use of an exhaustively elaborated database, with a significant number of images of the iris of healthy people and others suffering from the study diseases, makes iridology a technique that could be used as a rapid diagnostic method. All the operating systems available in the bibliography and their parts were reviewed, also reviewing the diagnostic capacity of each one of them. On the other hand, we compiled the studies published on the subject generally available today, both those that are declared in favor, and those that affirm that they are It is a useless diagnostic method with precision similar to that obtained at random. In conclusion, we consider that opinions on iridology are very divided, although the publications that use the scientific method to defend iridology outnumber those that position themselves against it. For all this, we consider that it would be interesting to have an open mind about iridology and apply it in more studies, since if it really had diagnostic capacity, it would be very useful and would save a great deal of time and money.


1.The rational basis, on which iridology is based, is clear and is exposed in books and articles.

2.There are several very opposite opinions about iridology. However, nowadays, this is a subject somewhat forgotten or even omitted by many health professionals, although several studies show that it is useful for diagnosis.

3 Insufficient evolution of iridology is observed in many cases and a methodology not very transparent and not very rigorous. This situation prevents us from knowing whether it is really a good diagnostic tool, hinders the development of the subject and prevents it from being used in the day-to-day life of many health professionals.

4. New technologies in iridology eliminate the subjectivity of the subject and allow can be used as a rapid method of screening and guidance in the diagnosis of various diseases.

5. It can be affirmed that the studies on the subject, for and against, are relatively equal and, on occasions, these positions are due to preconceived ideas by the authors. 6. After their complete review, it is concluded that the new methods are very precise, but they are not being used adequately, since most of the studies in which they have been applied are biased in other respects. Therefore, the future of iridology should be based on the correct application and research with the help of intelligent systems that have already been developed, this being a possible extension of this study

Author: Cano Llergo, M.J. (2020). Controversia sobre la iridología. (Trabajo Fin de Grado Inédito). Universidad de Sevilla, Sevilla.

Sevilla University. Double Degree in Pharmacy & Optics & Optometry:

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