What Makes your Eyes Unique?

The Science behind Eye Colour

Have you ever wondered why some people have blue eyes, while others have green, hazel or brown eyes? Eye colour is one of our most distinctive features, and no two people have exactly the same eye colour pattern. While genetics play a major role, the science behind eye colour is more complex than once believed. All about eye colour notes that, multiple genes influence eye colour, rather than a single inherited trait.

How is Eye Colour Determined?

Eye colour is largely determined by the amount and distribution of melanin, a pigment found in the iris, the coloured part of the eye. People with brown eyes have higher levels of melanin, while those with blue or grey eyes have very little melanin in the front layer of the iris. Green and hazel eyes fall somewhere in between. Eye colour is influenced by multiple genes, particularly the OCA2 and HERC2 genes, which help regulate melanin production. This explains why eye colour inheritance can be difficult to predict and why siblings can have different eye colours despite sharing the same parents.

What is the Most Common Eye Colour?

Brown eyes are the most common eye colour worldwide. Globally, the proportion of people with brown eyes is high, particularly across the US, Africa, Asia and South America. Green eyes are among the rarest natural eye colours, occurring in only a small percentage of the world’s population.

Eye Colour Myths

Many people have heard that all babies are born with blue eyes, but this is a myth. Some babies are born with brown eyes, while others’ eye colour changes during infancy as melanin develops within the iris. Another common misconception is that eye colour can be accurately predicted based on the parents’ eye colour alone, because several genes influence eye pigmentation, predicting a baby’s eye colour isn’t always straightforward.

Can Eye Colour Affect Eye Health?

While eye colour does not determine the quality of your vision, some studies suggest it may be associated with certain health risks. Research has found that people with lighter-coloured eyes may be more sensitive to bright light because they have less melanin to absorb it. People with darker eyes may have a slightly higher risk of developing cataracts, although many other factors, including age, genetics and UV exposure, play a much larger role. Regardless of eye colour, protecting your eyes from ultraviolet (UV) radiation remains important. Wearing sunglasses with UV protection can help reduce the risk of long-term eye damage.

Looking after Eyes of Every Colour

Whether your eyes are blue, brown, green, hazel or somewhere in between, maintaining good eye health is essential. Eye care experts recommend:

• Eating a diet rich in vitamins A, C and E.
• Staying physically active.
• Wearing UV-protective sunglasses outdoors.
• Taking regular screen breaks to reduce digital eye strain.
• Attending routine comprehensive eye tests.