Blue eyes are beloved around the world for their beauty and depth. Along with brown, green, and hazel, blue is one of the primary eye colors.
Between 8% to 10% of the world population has blue eyes. which are most common in Europe.
Baltic and Scandinavian countries such as Estonia, Finland, Sweden, and Iceland have some of the highest rates of blue eyes.
Continue reading to learn more about the prevalence of blue eyes around the world.
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What country has the most blue eyes?
European countries have higher rates of blue eyes than South America, Asia, or Africa. Blue eyes are recessive, so both parents need to carry the gene for a child to have blue eyes.
Here’s a list of the top 20 countries for blue eyes based on the percentage of the population with this physical trait.
- Estonia – 89%
- Finland – 89%
- Sweden – 78%
- Iceland – 75%
- Netherlands – 61%
- Denmark – 60%
- Ireland – 57%
- Norway – 55%
- Poland – 52.5%
- Scotland – 50%
- England – 48%
- Wales – 45%
- Slovenia – 44%
- Germany – 40%
- Belgium – 29%
- Ukraine – 25%
- France – 22%
- United States – 16.5%
- Spain – 16%
- Italy – 14%
What makes eyes blue?
Blue eyes are caused by lower levels of a brown pigment called melanin in the iris. People with dark-colored eyes have more melanin in the iris front layers, while less of this pigment is found in light-colored eyes.
What’s interesting is that most European and American babies have blue eyes when they are born, but then they change color within the first few years of life.
Just 1 in 5 Caucasians grow up to have baby blue eyes, as melanin production tends to increase with age.
Another fun fact is that all humans once had brown eyes. Blue eyes are thought to be caused by a genetic mutation originating with one ancestor around 10,000 years ago.
This individual is believed to have a mutated HERC2 gene, causing less melanin production.
The genetic mutation was then passed on from generation to generation, leading to the beauty of blue eyes as we know them today.
The more light melanin absorbs, the darker the iris is, while unabsorbed light is reflected. Eyes with low levels of melanin reflect light on the blue spectrum, resulting in rarer eye colors.
Also, some scientists and historians believe that brown eyes were a natural adaption for those in the Middle East and southern hemisphere dealing with intense sunshine.
People living in northern countries with milder conditions did not need the same level of protection against sun exposure, and the gene mutation allowed blue eyes to spread more in these areas.
Are blue eyes or brown eyes more common?
Brown eyes are more common than blue eyes. Brown is the most common eye color worldwide, with somewhere between 70% and 80% of Earth’s population having brown eyes.
In comparison, blue eyes account for just 8% to 10% of the population.
Brown eyes are dominant while blue eyes are recessive, which explains why brown is a much more prevalent eye color than blue.
If both parents have brown eyes, their child has a 75% chance of also having brown eyes, compared to an 18.5% chance of green eyes and a 6.5% chance of blue eyes.
People with brown eyes may have BB (two dominant genes) or Bb, compared to those with blue eyes who have bb gene models.
Both parents need to be Bb to produce blue-eyed offspring.
Are blue eyes or green eyes more common?
Although blue eyes are less common than brown, both are more prevalent than green eyes, which are the rarest in the world.
Around just 2% of the global population has natural green eyes, which have more pigment than blue eyes but less melanin than brown eyes.
Green eyes are more common in the U.S, due to the higher proportion of Irish and Scottish descendants.
About 9% of Americans have green eyes, compared to 25% with blue eyes and 45% with brown eyes.
In addition to blue eyes, hazel eyes are also quite rare, as a mix between green and brown eyes.
When the inside of the iris and the outer rim have different colors, eyes may appear hazel with flecks of green, brown, and gold.
Around 5% of people have hazel eyes.
What hair color goes with blue eyes?
People with blue eyes may have blonde, brown, or red hair. Dark brown or black hair is another possibility, although its much more common for dark-haired people to have brown eyes.
Keep in mind that 75% to 85% of the world’s population has black hair, followed by brown, blonde, and then red.
That puts blue eyes in the same rare category as blonde hair.
Much like people dye their hair to achieve a desired color, colored contact lenses are often used to achieve a different eye color.
For example, those with natural or dyed blonde or red hair may use blue contact lenses to cover their brown eyes and change up their appearance.
At the end of the day, natural light blue eyes are quite rare, unless you are in a Scandinavian country or the U.S.
Both blue eyes and red hair are recessive traits, so both parents need to carry the gene in order to pass it down to their children.
Even for red-haired people, which account for 1% to 2% of the total population, brown, green, or hazel eyes are much more likely.
Do blue eyes have health issues?
A lot of people want blue eyes, especially in the U.S and Europe where beautiful baby blues are widely celebrated and adored.
However, blue eyes may come with a few health risks that people should be aware of. For starters, light-colored eyes may be more sensitive to light, so those people are recommended to wear sunglasses while outside and eyeglasses when staring at screens with blue light.
Medical studies have also shown that macular degeneration and eye cancer aren’t as common in brown-eyed individuals, leading to the belief that melanin protects against some eye diseases.
That’s why people with blue eyes are encouraged to not only watch out for ultraviolet and blue light, but also make regular appointments with an eye doctor to make sure their health checks out.