A danger signal: Poet and lovers alike have often been struck by the beauty of blue eyes, but a new study has now linked it to greater risk of blinness at old age. Australian researchers have found that people with blue eyes and the smokers are more likely to lost vision at old age. The study conducted on 3,600 people from the Blue Mountains, west of Sydney, found that the chances of losing vision at old age for a smoker were four times than that of a non-smoker. People with blue rather than brown irises were at a highe risk of developing macular degeneration, in which central vision is lost as a person age, professor Paul Mitchell, of the Department of Opthalmology at the University of Sydney said.