Here's another reason to eat your veggies.
A British teen who doctors described as a "fussy eater" was partially blinded because of his diet, which consisted of nothing but fries, chips and the occasional slice of ham.
The case was reported Tuesday in the peer-reviewed Annals of Internal Medicine, the flagship journal of the American College of Physicians, and described how the boy had been treated for health problems related to his poor eating habits since he was 14.
"His diet was essentially a portion of chips from the local fish and chip shop every day. He also used to snack on crisps – Pringles – and sometimes slices of white bread and occasional slices of ham, and not really any fruit and vegetables," Dr. Denize Atan, who treated him at the hospital, told the BBC.
His family practitioner first prescribed him injections to treat a vitamin B12 deficiency and told him to change his diet when he came in reporting "tiredness," but the boy did not keep with the treatment, nor did he change his diet, according to the case study.
Tests also detected macrocytic anemia at the time, the study says.
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When he was 15, he started experiencing hearing loss, but MRIs showed no structural problems. Vision problems followed soon after, the case study reports.
Over the next two years, he progressively lost vision. Atan told the BBC that he met the criteria for registering as blind.
She said he had blind spots in the middle of his vision, making it hard to drive, read, recognize faces or watch TV, but his peripheral vision was still intact.
According to the case study, the boy had nutritional optic neuropathy, the condition for his vision loss, and avoidant-restrictive food intake disorder, the condition for his "fussy" diet.
Nutritional optic neuropathy is rare in purely dietary cases, the study says. The boy denied using drugs or alcohol, and his height and weight were average. In addition to a B12 deficiency, he also had low levels of copper, selenium and vitamin D. He had high zinc levels, too, and low bone density.
The teen also told doctors that he has refused to eat foods with certain textures since elementary school.
Doctors prescribed him nutritional supplements to treat his deficiencies and was referred to mental health services for his eating disorder. His vision stabilized but didn't improve, the case study says.
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Vision loss associated with poor diet is reversible if treated early, according to the study.
Atan told the BBC that the boy's case is rare, and parents should not be alarmed by their own children's fussy diets.
"It's best not to be anxious about picky eating, and instead calmly introduce one or two new foods with every meal," she told BBC.
According to the case study, his eating disorder is a relatively new one, too.
"Unlike anorexia nervosa, it is not driven by weight or shape concerns. Onset is in middle childhood, with lack of interest in food, heightened sensitivity to food textures, and fear of the consequences of eating," the article states.
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This article originally appeared on USA TODAY: Diet of fries and chips leads to teen's blindness, study finds