why does my eyes change color?

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Permalink Reply by Lost~Girl~Lydia on August 30, 2009 at 12:07pm

Most peoples eye colour changes from when they are little,
And right through the teenage years.
Children most commonly have blue eyes,
But because of pigment production, eyes do change colour.
Changes after this are mainly attributed to hormone changes :)

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Permalink Reply by The Spook on August 30, 2009 at 10:24pm

Changing eye color baffles people. It’s the most-asked question I get.

OK, all. 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, says Brian DeBroff, ophthalmology professor at Yale University.

Aging, however, is the usual cause of color change over time. So, yes, Mei, your mom is right. Color can change as we age. It does so for 10 to 15% of the normal Caucasian population.

"Some eyes become darker, but most become lighter with increasing age," says Richard A. Sturm, a Principal Research Fellow at the Institute for Molecular Bioscience at the University of Queensland in Brisbane, Australia.

And yes, Bryan, hazel eyes do change color. Hazel eyes, as well as any lighter eyes, usually darken with age. Hazel eyes are light brown or yellowish brown.

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. Why does it change? 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 colour," says Sturm. 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 colour 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.

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Permalink Reply by Mei (Peridot Birchstar) on August 30, 2009 at 10:31pm

thank you

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