How Common Are Hazel Eyes Compared to Other Eye Colors?

The prevalence of hazel eyes compared to other eye colors

Check out this answer from Consensus:

Hazel eyes are relatively uncommon, accounting for about 5% of the global population. The prevalence of hazel eyes varies among different populations and can be influenced by genetic factors. While hazel eyes are less common than brown or blue eyes, they are associated with specific health risks, highlighting the importance of understanding the genetic and environmental factors that contribute to eye color.

Eye color is a polygenic trait influenced by multiple genes and environmental factors. The most common eye color globally is brown, which accounts for approximately 79% of the population. Blue eyes are the next most common, found in about 8-10% of people. Hazel eyes are less common, present in about 5% of the population, while green eyes are the rarest, seen in only 2% of people1.

Factors Influencing Eye Color

The color of the iris is determined by the amount and type of pigments present, primarily melanin. The genes involved in melanin production and distribution, such as HERC2 and OCA2, play significant roles in determining eye color. Single nucleotide polymorphisms (SNPs) in these genes can lead to variations in eye color, including hazel1 3 6.

Hazel Eyes in Different Populations

Studies have shown that the prevalence of hazel eyes can vary significantly across different populations. For instance, in a study conducted on a Saudi population, the prediction model for eye color showed lower accuracy for hazel eyes compared to brown and intermediate colors, suggesting that hazel eyes are less common and more complex to predict in this group3. Similarly, research on an Iraqi population indicated that the genetic markers associated with hazel eyes showed non-significant effects compared to other eye colors6.

Changes in Eye Color Over Time

Eye color can change during the early years of life. A study following newborns over two years found that while brown eyes were the most stable, blue eyes were more likely to change to other colors, including hazel. However, the overall prevalence of hazel eyes remained relatively low2.

Health Implications of Hazel Eyes

Hazel eyes, like other light-colored eyes, have been associated with certain health risks. For example, individuals with hazel or green eyes have a higher risk of developing uveal melanoma compared to those with brown eyes4. Additionally, light eye colors, including hazel, have been linked to an increased risk of certain skin cancers, such as squamous cell carcinoma and basal cell carcinoma5.