Less than 2 percent of the worldwide population has naturally green eyes. Green is one of the rarest eye colors. The green color of the eyes is formed when there is a low amount of melanin in the iris and a varying amount of lipochrome. How these two factors balance out determines whether the person has light green, bluish green, yellowish green, dark green, or brownish green eyes.
To have light green eyes, the person has to have a small amount of melanin mixed with a large amount of lipochrome in her eyes. The higher the amount of melanin, the darker or more brown the eyes will appear. The amounts of lipochrome and melanin balance each other out in the eyes, which means no one can have a high amount of both lipochrome and melanin in the eyes. Women are more genetically disposed to have truly green eyes. Green eyes are most common in northern and central Europe, though people with green eyes can be found in western Asian cultures. Hazel eyes are often confused with green eyes because both share a yellowish, or gold, pigment. Hazel eyes have more of a brown appearance and may appear to change color in different types of light while green eyes have less melanin.