NAT 203

Historical Modalities I: Iridology Online


Can we tell the constitution or health issues from the iris of the eye? This course leads students through the theories of iridology, from historical to modern-day, including the modern controversies and conflicting information from the fields of identification. Learn the basis of this modality and decide for yourself.

Upon completion of this course, students will earn the Integrative Iridology Specialist™ micro-credential and verified badge to demonstrate their iridology knowledge. Learn more online here.

Learning Outcomes

  • Identify and explain constitutional classifications.

  • Describe and explain the structure and function of the eye.

  • Explain the healing crisis and Hering’s Law.

  • Identify zones, segments, structural, and colored signs in the iris and understand their implications.

  • Explain the history and theory of iridology, analyzing the iris of the eye in relation to the body’s health.

  • Understand the importance of the eliminative organs for optimal health.

  • Explain and discuss the iris chart.

  • Discuss the four stages of tissue health as seen in the iris.

  • Discuss the benefits of iris photography.

  • Recommend nutrition, herbal supplements, and lifestyle changes for various conditions identified through iris analysis.

More details

Required Course Pack:

  • ACHS eTextbook: Petersen, D. (2018). NAT 203: Historical Modalities I: Iridology (18th Edition).
    Portland, OR: American College of Healthcare Sciences. (Optional: Printed copy available for an additional fee)
  • Online Materials and Library Resources (OMLR)
  • NAT 203 Practical Lab Kit:
    • Acetate Iridology Grid
    • Iridology Desk Chart 8-1/5″ x 11″
    • Iris Chart (credit card/wallet size)
    • Illuminated 10x Iridology Lens hand-held
    • Iridology Self-Analysis Compact 15x with Light

Total Course Price:

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None – Prior or concurrent anatomy & physiology training is recommended

Current Instructors:

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Admissions Requirements:

Minimum of a high school diploma or equivalency and recommendation for admission by the ACHS Admissions Committee.

Total Course Price:

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