Hi, I m 15, 125 pounds which av. for my height, and I ve noticed for a few years now that I have a thin strip of greyish blue at the top of my iris- on both eyes. I have dark brown eyes and the single strip is layered almost on top of my natural brown pigment. I don t think this is normal, is it cataracts? Also, my eyesight has not been affected and I sleep for an average of 7hours or less a night.