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FriJul 12

National Different Colored Eyes Day – July 12, 2024

National Different Colored Eyes Day on July 12 is all about heterochromia iridum. It’s okay, we didn’t know what it meant at first, either. Heterochromia iridum is a term for the variation in color that gives a single organism two different colored eyes. It has been known to occur in populations of many species since the dawn of recorded history and is an interesting and sought-after trait. Only the lucky 1% of the population enjoys this special pigmentation, though there are three distinct types of heterochromia. Today, many people prefer pets with this fun eye color difference, and colored contact lenses are used just to mimic the trait! All this to say, give your friends with heterochromia a little extra love today.

History of National Different Colored Eyes Day

While today, people with two different-colored eyes are likely to get a compliment, that was far from the case through history. For example, Native American Indians used to believe that those born with the unique coloring could see both heaven and earth through their “ghost eyes.” Because they had seen dogs born with the trait, they found it inhuman and ghostly.

Many myths and fears have long been associated with heterochromia iridum, including superstitious beliefs that those with the trait were witches, were evil, could see beyond their own deaths and into the afterlife, or could consort with ghosts and spirits. Since eyes are the windows to the soul, ancient peoples who couldn’t explain the abnormality quickly resorted to ghostly explanations that painted the trait as making someone less-than-human.

Today, of course, our society finds it beautiful! However, it’s not widely understood. Did you know it can either appear at birth or be acquired? Especially if it’s acquired, it’s recommended to see a doctor just to ensure the condition is benign. While the vast majority of cases are completely harmless and simply pretty, some can indicate eye damage or that there is another underlying disease. Better safe than sorry!

There are actually three different kinds of heterochromia iridum – complete, segmental, and central. Central, the most common, appears as matching irises with different colors encircling the pupils. Many don’t know this classifies as heterochromia iridum! Segmental heterochromia appears as a different patch of color in only one iris, and complete heterochromia is the most iconic – two irises of different colors.

Whether genetic or not, the total percentage of the population with the trait is less than one half of one percent. If you want to know if there’s a chance it’s in your genes, comb through some old family photos! Keep in mind it can be very hard to discern – the majority of people actually don’t notice the condition in someone else, and it can be very easily mistaken.

National Different Colored Eyes Day timeline

4000 BCE
Eye Colors Emerge

It was around this age when humans, who had up until this point only had brown eyes, started to display a genetic mutation allowing for different eye pigments!

300s BCE
Heterochromia Named

The credit for discovering heterochromia is often given to Aristotle, who named it “heteregloucos.”

Beginnings of Optometry

Though Islamic scientists were studying eyes as early as the 10th century, Italian transformed knowledge of the human eye in the 15th century with a new understanding of the physical form of the eye.

The First Eye Hospital

The first hospital dedicated to the practice of ophthalmic was established in London.

Ophthalmoscope Invented

This Ophthalmoscope was created to inspect the retina, has led to new understanding and new subspecialties in the optometry field since it became widely known.

National Different Colored Eyes Day FAQs

Where is National Different Colored Eyes Day celebrated?

The United States.

Are there other National holidays about eyes?

There are many National observances about eyes, including January – Glaucoma Awareness Month, May – Healthy Vision Month, and March – Workplace Eye Wellness Month.

What other National holidays fall on July 12?

Yes! July 12 is also National Simplicity Day and Orangemen’s Day.

How to Celebrate National Different Colored Eyes Day

  1. Learn more about heterochromia

    Heterochromia iridis comes in many forms, and in many species. Spend a few minutes looking it up today and learning more about what makes these lucky individuals so special!

  2. Post it up

    If you’re one of the lucky few who can wield the captivating gaze of two differently-pigmented eyes, share your best selfie on a social media platform with a hashtag. While having two differently-colored eyes is indisputably stunning, sometimes accepting things that make us different can be challenging - someone else with heterochromia may feel inspired or confident just from your selfie.

  3. Shout out a friend or celebrity with heterochromia

    If you have a unique friend with two different colored eyes, give their selfie and like or comment to boost it! If you don’t, go give some love to a celebrity with the condition - choose from Kate Bosworth, Jane Seymour, Dan Aykroyd, Henry Cavill, Mila Kunis, Josh Henderson, and more!

5 Fun Facts About Different Colored Eyes

  1. Heterochromia is usually benign

    Translation: having different colored eyes is almost never an eye disease, and almost never will affect your vision.

  2. Stars - they have heterochromia just like us!

    Dan Aykroyd, Mila Kunis, Henry Cavill, and more all have heterochromia.

  3. Man’s best friend

    The breeds of dogs that most often have heterochromia are Siberian huskies, Australian shepherds, collies, corgis, and Chihuahuas.

  4. Born to be odd

    Some animals like “odd-eyed cats” are bred specifically to have this genetic feature!

  5. Heterochromia mistaken for anisocoria

    Anisocoria, which is when a person has two different pupil sizes, can sometimes be mistaken for having two different colored irises - take David Bowie for example!

Why We Love National Different Colored Eyes Day

  1. t’s a celebration of diversity

    Part of what makes heterochromia iridum so striking is that it’s so rare! Human beings come from all walks of life and no one has exactly the same coloring. The more we can celebrate the little things that make others unique, the more we can accept the differences we have ourselves.

  2. It’s striking and captivating

    The gaze from a person with two different colored eyes is stunning! It’s a look that no one is soon to forget, and it’s obviously envious - people often buy colored contacts just to mimic the natural look. If you’re one of the lucky few with different colored eyes, take a second to appreciate it today!

  3. It’s artistically inspiring!

    Many pieces of art center on people with different colored eyes, as the striking gaze is so unique and inspiring. Makeup art also has made heterochromia iridum a trend that is accessible to any artist with colored contacts and a flair for the dramatic.

National Different Colored Eyes Day dates

2024July 12Friday
2025July 12Saturday
2026July 12Sunday
2027July 12Monday
2028July 12Wednesday

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