What Causes Grey Eyes? Are They Rare?
Grey eyes are one of the rarest eye colors. Less than 3% of the global population has grey eyes. They’re most commonly found in people of Northern and Eastern European ancestry.
Like all eye colors, they’re a product of the amount of melanin in the iris. The iris is a circular, thin layer in the center of the eye.
When light hits the iris, it scatters in various ways, depending on the level of melanin present. This is known as Rayleigh scattering. It’s what determines what color your eyes look.
People with light-colored eyes have very little melanin compared to those with brown-colored eyes. Those with green or hazel eyes have less; those with blue even less; those with grey, none at all.
In addition, people with grey eyes have more collagen in their stroma, a layer of their iris. This also affects how light scatters and is what causes their eyes to appear grey rather than blue.
A person’s genes determine how much melanin they have in their iris. There are at least 16 different genes that influence eye color. Scientists are still studying exactly how these genes all interact with each other.
What Grey Eyes Look Like (Pictures)
Grey eyes can come in several different shades, from light to dark grey. They can come close to blue, which is why grey and blue eyes are often conflated. Grey-green and grey-hazel variants are also possible.
9 Facts About Grey Eyes
Here are nine interesting facts about grey eyes:
1. Grey-eyed Estonia
Blue and grey eyes are often conflated together, making statistics on grey eyes murky at times. That said, Estonia may have the highest percentage of grey-eyed people. Almost 90% of the population has either blue or grey-blue eyes.
2. More Likely to Drink
A study compared rates of alcohol dependence between those with light-colored eyes and those with dark eyes. It found a 54% higher rate of alcohol dependence among those with blue, green, light brown, or grey eyes.1
3. Changeable with Mood
Grey eyes change with the mood of the person. This is due to how their pupils narrow or widen, which compresses or loosens the colors in the iris.
4. Linked to Wisdom
The Ancient Greeks associated grey eyes with wisdom. This may be due to the fact that the goddess of wisdom, Athena, had grey eyes.
5. Protection Against Disease
Grey eyes may mean greater protection against certain skin or autoimmune disorders. Researchers think people with grey eyes are less likely to have vitiligo. This is a skin disorder that is associated with diabetes, arthritis, and lupus (among other things).
6. Less Sensitive to Pain
A study found that pregnant women with brown or hazel eyes reported higher levels of pain than lighter-eyed women.5
7. More Sensitive to Sunlight
Due to their lack of melanin, people with grey eyes are more sensitive to sunlight, a condition known as photophobia.
8. More Competitive
A study in Current Psychology found that grey-eyed people are more likely to be competitive than those with dark eyes.
9. More Strategic
A study at the University of Louisville analyzed the reaction times of people by eye color. Brown-eyed people performed better in fast-paced sports like football and hockey.
But people with grey eyes succeeded more at less reactive, more deliberate activities. These included things like golf, cross-country running, and studying for exams.4
Are People With Grey Eyes More at Risk for Eye Problems?
Like other light-eyed people, people with grey eyes are more susceptible to ocular melanoma, also known as eye cancer. This is cancer of a layer of the eye called the uvea.
Complications from ocular melanoma include glaucoma, vision loss, and the possible spread of cancer to other parts of the body.
Fortunately, ocular melanoma only affects six of every million people in the U.S. each year, making it pretty rare.6
What are Some Benefits of Grey Eyes?
People with grey eyes are perceived as more intelligent, calm, and profound. They’re also less likely to have certain skin diseases or autoimmune disorders.
Grey eyes may also be considered attractive because of their rarity, particularly if you are a woman. In a 1000-person poll done by 1800Contacts, men ranked women with grey eyes as the most attractive.
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