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Eternal Cynic
Guest
Pigment in the front layer of the iris (called the stroma) colours the iris. Eye colour lightens when pigment granules drop in number, or when the granules make a lighter colour. The iris can also lose colour if the pigment degrades. Eyes, unlike skin and hair, do not synthesize colour pigment continuously. Instead, eyes keep pigment granules made earlier. So, if the pigment degrades, the eye colour lightens. Eyes can also change colour with age - but that is surely not your problem. Eyes may also change colour due to disease. Hopefully, that is not the case, but do consult the doctor to be absolutely sure.