Poor diet caused blindness in young “fussy eater”

A poor diet caused a young patient's blindness, according to a new case report published in the Annals of Internal Medicine.

According to the authors, nutritional optic neuropathy should be considered in any patient with unexplained vision symptoms and poor diet, regardless of body mass index (BMI).

Researchers from the Bristol Eye Hospital in England reported the case of a 14-year-old patient who first visited his family physician complaining of tiredness. Aside from being labeled a "fussy eater," the boy had a normal BMI and took no medications.

Tests showed macrocytic anemia and low vitamin B12 levels, which were treated with vitamin B12 injections and dietary recommendations. By age 15, the patient had developed sensorineural hearing loss and vision symptoms, but no cause was found. By age 17, the patient's vision had become progressively worse, to the point of blindness.

The physicians investigated the patient's nutrition and found vitamin B12 deficiency, low copper and selenium levels, a high zinc level, and markedly reduced vitamin D level and bone mineral density. The patient confessed that since elementary school, he had avoided foods with certain textures and only ate French fries, potato chips, white bread, processed ham slices, and sausage. By the time his condition was diagnosed, the patient had permanently impaired vision.

The risks for poor cardiovascular health, obesity, and cancer associated with junk food consumption are well known, but poor nutrition can also permanently damage the nervous system, particularly vision. Nutritional optic neuropathy is a dysfunction of the optic nerve usually caused by malabsorption, drugs, or poor diet combined with alcoholism or smoking. It is rare in developed countries. The condition is potentially reversible if caught early, but if left untreated, it leads to permanent blindness.

The researchers said they hope to alert clinicians of the visual complications of a diet restricted to processed junk food.