Separate news stories arising in the last two weeks have revealed that two unrelated English boys have gone blind, after eating only junk food such as fries, chips and chocolate.
The first case, reported in the peer-reviewed Annals of Internal Medicine, described how the boy, known only as Jake, 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 stick with the treatment, nor did he change his diet, according to the case study.
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.
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 had refused to eat foods with certain textures since primary school.
The second case study reported relates to 18-year-old Harvey Dyer, who concerned his mum Kerry James when he told her he was unable to see out of his left eye suddenly last October.
Kerry took Harvey to their local optometrist who said he should go straight to hospital. Doctors carried out tests and found all of his vitamin and mineral levels were dangerously low. Medics put the vision loss down to lack of nutrition in his diet.
Mum Kerry explained that Harvey, who has ADHD and autism, has eaten the same foods since he was two.
She said: “He only eats chips, Quavers, Wotsits (similar to Cheetos and Cheezels) and Dairy Milk chocolate for every meal.
“Harvey was diagnosed with ADHD and is on the autistic spectrum so we’ve always put it down to textures.
“He can’t physically eat anything else — he won’t even take things like medicine. We’ve tried anything and everything — it’s been so hard.”
Kerry says she’s fought to get him help and even had a paediatric team come and sit with them at meal times.
She added: “It’s not that he doesn’t want to eat other foods — he really does.
“He has asked about hypnotherapy and we’ve been to eating disorder clinics.” She said that they believe he also has the avoidance restricted food intake eating disorder, as Jake does.
It is believed these cases are rare, and parents should not necessarily 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," Dr Atan told the BBC.
"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.