The millions of rods and cones in the retina at the back of each of your eyes, which turn light into nerve signals to send to the brain, use a lot of energy. So the retina tends to burn out faster than the rest of the body. But now scientists have found that short bursts of a red light shone into your eyes could help reduce or even reverse this ageing process. Katie Haylor spoke to Glenn Jeffery, who's been looking at a group of 24 people with no eye disease for the study... Like this podcast? Please help us by supporting the Naked Scientists