Eye color can change over time because of age or, unfortunately, disease.
Eye disease is a cause of color change. So, ask a doctor to examine your eyes if you notice a slow loss of color. The change could be due to Fuch’s heterochromic iridocyclitis, Horner’s Syndrome, and pigmentary glaucoma,
Aging, however, is the usual cause of color change over time. So, yes color can change as we age. It does so for 10 to 15% of the normal Caucasian population. These people’s eyes change slowly over many years after they reach adolescence.
Some eyes become darker, but most become lighter with increasing age
How and why eye color changes. Pigment in the front layer of the iris (called the stroma) colors the iris. Eye color lightens when pigment granules drop in number, or when the granules make a lighter color. See figure. The iris can also lose color if the pigment degrades.
Eyes, unlike skin and hair, do not synthesize color pigment continuously. Instead, eyes keep pigment granules made earlier. So, if the pigment degrades, the eye color lightens.
Likewise, eyes can darken if the number of pigment granules increase or if the granules make darker pigment.
That’s how the color changes. Genetics is the key as experimenters learned by studying twins. They observed the eyes and skin of identical twins and non-identical twins of American Caucasians between the ages of 3 months to 6 years.
Both sets of twins showed a darkening with age of both the hair and eye color. The identical twins changed color together, at essentially the same rate. The non-identical twins changed color but at different rates, which indicates a "strong genetic influence in the timing of these color changes."
Eye color probably changes for the same reason we have one head instead of two: genes. Genes determine all body characteristics — including changing eye color as we age.
No it might be exposing them to sunlight. Also if you have contacts...So I dyed my hair and now my roots are lighter ..