structure image How Common Are Blue Eyes?


Blue is a somewhat rare yet striking eye color, making it a memorable facial feature. From light blue eyes to shades of blue-gray, these eyes don’t actually contain blue pigment. Rather, they appear blue because they don’t have as much of the brown pigment present in dark-colored eyes.  


Keep reading as we discuss what determines blue eye color, whether you can change your eye color, and the benefits and risks that people with light-colored eyes may have.  

Where Do Blue Eyes Come From? 

Eye color, in general, is determined by your genetics and a substance in your body called melanin. 


This is the pigment that provides color to your eyes, skin, and hair. People with more melanin usually have darker features. Those with less melanin have lighter features. They also have more of a certain kind of melanin compared to people with darker eyes. 


Eye color is created by the amount, distribution, and type of melanin present in the iris, or the colored area of your eye.  


The iris consists of two layers: the stroma (front layer) and the pigment epithelium (back layer). The levels of melanin in each of these layers are what gives your eyes their color. 


Most eyes have brown pigment in the back layer of the iris. Those with brown eyes typically have a lot of melanin in both layers, while those with light eyes have little to no melanin in the front layer. If your eyes are blue, there’s no pigment in the front layer. 


This distribution of melanin affects how light is reflected in the iris. Fibers in the iris absorb longer wavelengths of light as they enter the eyes, making the eyes look blue.  


Genetics play a role in determining your eye color. In the past, scientists believed that one gene controlled the color of eyes you inherited and that you could only have blue-colored eyes if both of your parents had blue eyes. However, they now know that multiple genes are involved in eye color inheritance and that parents can have children with eye colors different than their own.  

Are Blue Eyes a Mutation? 

A genetic mutation is believed to be the cause of blue eyes. A genetic mutation is a change in DNA sequence that occurs during DNA replication when cells divide.  


The blue eye genetic mutation is associated with a reduced amount of pigment (melanin) in your irises, causing your eyes to appear blue. 

How Many People Have Blue Eyes? 

Blue is the second most common eye color after brown. It occurs in 8% to 10% of the global population. 


Many people in Northern Europe have blue eyes. You’re most likely to find them in: 

  • Finland
  • Estonia
  • Iceland
  • Sweden

Around 27% of the U.S. population has blue eyes. 

Are All Blue-Eyed People Related? 

If you share the same blue eye color with someone else, it could be that you’re (very) distantly related. Research suggests that you may share a common ancestor who had the same blue-eye genetic mutation. It’s believed that 6,000 to 10,000 years have passed since this genetic mutation first occurred.  

Can You Change Your Eye Color?  

Wearing colored contact lenses is the most common and safest way to change or enhance the appearance of your eye color. Though there are eye-color-changing procedures designed to alter the irises, they may not be safe and generally aren’t recommended. 


If you’d like to experiment with your eye color, you may be able to get a prescription for colored contacts even if you don’t need them for vision correction. For more information, ask your eye doctor for advice to see if they’re safe for your eyes.   

Benefits and Limitations of Having Blue Eyes 

Having blue eyes carries some benefits. But it may also increase your risk for certain eye conditions: 


Blue and other light eye colors may help protect against health concerns such as: 


Cataracts occur when the eye’s natural crystalline lens becomes clouded, causing blurry vision and other symptoms. This condition is common in older adults.  


Eye health researchers note that if you have light-colored eyes, you may have a lower risk of developing cataracts compared to those with dark eyes. However, sun exposure is a risk factor for cataract development. You should wear sunglasses with lenses that have 100% UV protection no matter what color of eyes you have. 

  Seasonal Affective Disorder 

People with blue eyes may be less likely to develop seasonal affective disorder (SAD) than those with brown eyes. This is a form of depression that occurs at certain times of the year, often in winter when daylight hours are shorter. It’s more common in areas of the world where winters are long, dark, and cold, such as in the far northern hemisphere regions. 


Further research is needed to confirm the connection between eye color and the risk of SAD. 

Limitations and Risks 

Having blue eyes could increase the risk of developing certain eye conditions, including:  

  Sun damage 

Melanin helps protect your eyes from UV radiation. Reduced melanin production can raise your risk of light sensitivity. It can also make your eyes more susceptible to sun damage.  

  Eye cancer 

Reduced melanin concentration may also be associated with an increased risk of ocular melanoma, a rare eye cancer.  


Wearing sunglasses with 100% protection against UVA and UVB rays can help reduce these risks. 


No matter what color your eyes are, you should keep up with regular eye exams to ensure you have no vision-related issues or signs of UV damage. Your eye doctor can also check whether you need a new vision prescription.