孫繼艷

Eating a diet of French fries， Pringles and white bread was enough to make one teenage boy lose his sight， according to a case study published in a medical journal. Scientists from the University of Bristol examined the case of a young patient whose extremely picky eating led to blindness， and have warned of the dangers of a poor diet.

The boy patient told doctors he had only eaten fries from the fish and chip shop， Pringles potato chips， white bread， slices of processed ham and sausage since primary school. He first visited a doctor at age 14， complaining of tiredness. He wasn’t taking any medicine， had a normal BMI and height， and showed no visible signs of malnutrition. Doctors discovered low vitamin B12 levels and anemia， treating the patient with vitamin B12 injections and advising him to have a healthy diet.

One year later there were signs of hearing loss and decreased vision symptoms（視覺癥狀）， but doctors did not find the cause. The patient’s extreme diet led to nutritional optic neuropathy（營養(yǎng)性視神經(jīng)病變）. He couldn’t see by 17 years of age， and doctors found vitamin B12 deficiency， low copper and selenium levels， a high zinc level， which reduced vitamin D level and bone density level， according to a statement from the University of Bristol. By this stage， vision damage could not be recovered.

Researchers from Bristol Medical School and the Bristol Eye Hospital examined the case and concluded that the patient suffered nutritional optic neuropathy. In developed countries it is rarely caused entirely by poor diet because food is easy to get.