David Bowie's eyes, which appeared to be of different colors, were difficult not to notice. Bowie had a condition called anisocoria - which meant his pupils were different sizes. That was a consequence of a serious injury at school in 1962 when his friend George Underwood punched him in the left eye during a fight over a girl, and doctors feared he would become blind in that eye, but his pupils only remained different in size. This gave the illusion of a difference in color, explains. The left eye yet appears to look grayer and/or darker.

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