In babies, the change in eye color is a result of the development of pigmentation. For adults the change in eye color could be a warning sign of some serious medical conditions. As many as 15% of Caucasian adults have some change in their eye color as they age, typically from darker to lighter, but if an adult's eyes change color dramatically, suddenly or the change is noted in only one eye, he or she should seek immediate medical attention. It could be the result of conditions such as fuch's heterochromic iridocyclitis, horner's syndrome and pigmentary glaucoma. Throughout our lifetime, the human eye may appear to change colors, even if the effect is only slight, because of lighting, mood and to some extent, what we are wearing. The iris, which is the colored part of the eye, is a muscle which in part controls the size and shape of the pupil. The pupil is wider in times of low light and is narrower in times of bright light. When the iris expands or contracts around the pupil, the pigments of its surface are either spread out or compressed together affecting the color that we perceive. In addition, certain emotions may cause the pupils to dilate and thus change the color of our eyes. What we wear doesn't actually cause a physical change in the color of our eyes; however the perception of our eye color can be affected by the clothing, makeup or jewelry that we are wearing.
