Eye color is one of the most distinctive features of human appearance. The color of the iris, the pigmented structure surrounding the pupil, determines someone’s eye color. Eye color is also one of the most hereditary human traits, with genetic factors playing a major role. There are three main genes that determine eye color, and various combinations of these genes produce different hues. The most common eye colors are brown, blue, hazel, and green. But even within these broad categories, there is variation in shade, intensity, and pattern. So what is statistically the most popular and common eye color among humans worldwide?
Factors That Determine Eye Color
Human eye color originates with three distinct genes, located on different chromosomes:
– HERC2 gene – Determines whether eyes will be brown or blue
– OCA2 gene – Influences degree of brownness/greenness
– SLC24A4 gene – Controls amount of melanin in iris
The HERC2 gene determines whether eyes will be brown or blue. The OCA2 and SLC24A4 genes then modify the amount of melanin pigment produced, with more melanin resulting in darker eyes. Here is a quick overview of how these genes interact to produce common eye colors:
Brown Eyes
Most humans worldwide have brown eyes. This is the dominant eye color resulting from high amounts of melanin on the OCA2 gene. Dark brown eyes have very high levels of melanin.
Blue Eyes
Blue eyes contain low levels of melanin. They occur when the HERC2 gene “switches off” the ability to produce brown eyes. The OCA2 gene also regulates the melanin content, causing blue eyes to range from light to dark blue.
Green Eyes
Green eyes result from moderate amounts of melanin, produced when the OCA2 gene has less melanin than brown eyes but more than blue eyes. The exact shade of green depends on the quantity of melanin present.
Hazel Eyes
Hazel eyes shift between brown and green, containing a small amount of melanin on the OCA2 gene. They often appear greenish-brown or brownish-green.
Gray Eyes
Gray eyes, like blue eyes, have low levels of melanin. However, they additionally have high amounts of collagen in the stroma that reflect light and make the eyes appear more blue-gray.
Global Distribution of Eye Colors
The prevalence of different eye colors varies significantly across global populations based on ancestry and genetics. Here is an overview of the worldwide distribution of eye colors by geographic region:
Europe
– Northern/Eastern Europe: Light eye colors like blue and green are most common. Over 75% of people have light eyes due to low melanin levels.
– Southern Europe: Darker eye colors like brown are more prevalent due to higher melanin levels from genetic ancestry. Still, light eyes appear at rates of 20-40% in countries like Italy and Spain.
Africa
Brown eyes approach 100% prevalence across indigenous African populations. Dark brown eyes are nearly universal due to very high melanin levels. Blue and green eyes are extremely rare.
Asia
– East Asia: Brown eyes overwhelmingly predominate, with over 95% of Chinese, Japanese, and Korean people having brown eyes.
– South/Central Asia: Again, brown eyes are most common, though lighter eyes are slightly more prevalent than East Asia with 5-10% of people having green/blue eyes.
Americas
– Native Americans: Almost all indigenous Americans have brown eyes.
– European descent: Have higher levels of light eyes, around 30-60% of the population.
– Mixed ancestry: Varies based on parental eye colors and genetic heritage.
This demonstrates that brown eyes are clearly the most common worldwide, though prevalence varies by region, as described below.
Global Eye Color Statistics
Taking a numerical approach using large-scale research studies and surveys, global eye color percentages shake out as follows:
| Eye Color | Global Prevalence |
| Brown | 55% |
| Blue | 17% |
| Hazel | 14% |
| Green | 11% |
| Gray | 2% |
| Amber | 1% |
This data demonstrates that brown eyes are by far the most common eye color found across humanity, with over half the global population having brown eyes. Blue eyes rank second, found predominantly in northern/eastern Europe. Hazel, green, gray, and amber eyes occur much less frequently among humans worldwide.
The following sections provide more detailed discussion on the prevalence of the two most common eye colors – brown and blue.
Brown Eyes
As seen above, brown eyes are decisively the most common eye color globally. Overall, approximately 55% of the world’s population has brown eyes. The prevalence is highest among indigenous populations of Africa, East Asia, South Asia, Southeast Asia, Native Americans, and Hispanic/Latino persons.
Here is a more precise breakdown of brown eye demographics worldwide:
| Region | Brown Eyes |
| Africa | 99-100% |
| East Asia | More than 95% |
| South Asia | 75-90% |
| Southeast Asia | 70-80% |
| West Asia | 65-75% |
| Native Americans | More than 90% |
| Hispanic/Latino (U.S.) | 70-80% |
In regions like northern and eastern Europe with high levels of lighter eye colors, brown eyes still make up around 30-35% of the population. Even in predominantly light-eyed countries, brown is the second most prevalent eye hue.
Clearly, brown eyes are the undisputed most common eye color globally. Their high melanin content provides greater protection from sun damage compared to light eyes. This makes brown eyes an evolutionary advantage in sunny climates near the equator, leading to their extremely high frequency among indigenous persons of Africa, Asia, the Americas, and Latin countries.
Blue Eyes
After brown eyes, blue is the next most common eye color across the world’s population. Approximately 8-10% of the global population has blue eyes. In terms of numbers, there are an estimated 575 million blue-eyed people worldwide.
Here are the regions with the highest percentages of blue eyes:
| Region | Blue Eyes |
| Northern Europe | More than 75% |
| Eastern Europe | 40-60% |
| Southern Europe | 20-40% |
| European descent (U.S./Canada) | 20-30% |
Blue eyes reach peak frequencies in countries like Finland, Germany, Poland, and the Baltic states, where up to 80% of the native populations has blue eyes. Moving south into areas like Italy, Greece, and Spain, the numbers drop to around 20-35% blue eyes. Among European descendants in the United States and Canada, blue eyes occur in about one-quarter of the white population.
Outside of Europe, blue eyes start to become very rare. Less than 1% of indigenous Africans, Asians, and Native Americans have blue eyes. Overall, when considering the entire global population, blue eyes only account for around 8-10% of people worldwide.
But while not the most common eye color, blue eyes remain one of the most culturally celebrated and coveted eye hues. Their vibrant color captures attention and displays a unique beauty.
Conclusion
In conclusion, brown eyes unequivocally represent the world’s most common eye color, with over half the global population having brown eyes. Africa, Asia, the Americas, and Latin countries all have extremely high frequencies of brown eyes among native populations. While rarer outside of Europe, blue eyes are the second most prevalent color, appearing in around 8-10% of humans worldwide. Cultural perceptions aside, the statistics clearly show brown eyes are numerically the most popular eye color globally based on genetic ancestry and human migration patterns over thousands of years. So if you have brown eyes, you have the world’s most common eye color – something to appreciate and enjoy!
