A very finicky British 17-year-old saw very bad results from a diet of French fries, Pringles chips and white bread: He went blind. University of Bristol researchers said the boy’s unhealthy diet was mostly unchanged since he was 14, when he complained of tiredness to his regular doctor, according to a university press release. At first, doctors noticed nothing particular about the boy, aside from being a “fussy eater.” His body mass index and height were normal, he had no visible signs of malnutrition, and he took no medications. A year later, the teen’s doctor noted hearing loss and “vision symptoms,” according to the researchers, but “no cause was found.”