Rates of childhood myopia have soared worldwide, with one in two people expected to be short-sighted by 2050. Helen Coffey investigates this global rise and digs into the lifestyle changes that could actually make a difference M yopia – otherwise known as short-sightedness – used to be considered a hereditary inevitability. If your parents needed glasses , chances were, you would too. It was just the luck of the draw. But times have changed (and not for the better). For those born between 1939