A teenager is believed to be the first in the UK to go deaf and blind due to his junk food diet, a report has warned.
The 17-year-old lived off a daily portion of chips, crisps, white bread and processed meat for around a decade.
His poor diet, which resulted in a number of vitamin deficiencies, led to the boy developing a condition called nutritional optic neuropathy (NON).
More commonly seen in malnourished children in developing countries, purely dietary causes of NON are rare in the western world.
It manifests in damage to the optic nerve, which leads to sight loss and if undiagnosed, blindness.
The unnamed patient, from Bristol, also developed hearing loss and bone weakness.
Since primary school he suffered from a rare eating disorder, avoidant-restrictive food intake disorder (ARFID).
Sufferers become sensitive to taste, texture, smell or appearance of certain foods. He had previously told doctors he did not like the “texture” of fruit and vegetables.
Dr Denize Atan, of University Hospitals Bristol NHS Foundation Trust, who co-authored the report published in Annals of Internal Medicine, and treated the patient, said there is a lack of awareness among healthcare professionals and the public about the link between poor diet and sight loss.
“What’s unusual about this case is the extreme picky eating and the fact it had gone on for quite some time, that the diagnosis had been missed and the visual loss had become permanent,” Dr Atan told The Telegraph.
“The link between poor nutrition and vision has been known about for quite some time, at least among specialists in neuro-ophthalmology. The problem is that awareness among other health professionals isn’t quite so high.”
Scientists have previously raised concerns that the majority of British diets are increasingly made up of poor quality, processed foods.
A study of 19 European countries by the the University of Sao Paulo last year found that UK families buy more ultra-processed food than any others in Europe, amounting to 50.7 per cent of the diet.
The boy was first taken to see his GP aged 14 complaining of tiredness. He was labelled a “fussy eater”, but took no medications and was otherwise healthy.
Blood tests revealed he was anemic due to a B12 deficiency, which causes fatigue and he was treated with vitamin injections.
Aged 15 his hearing began to deteriorate, followed by his sight, but despite having an MRI scan no structural damage to his ears was detected.
After two years of progressive loss, his vision was measured to be 20/200, rendering him legally blind.
By 17 the vitamin B12 injections he had been prescribed had lapsed, and he also had low copper and vitamin D levels, as well as poor bone mineral density.
He was then diagnosed with NON, but Dr Atan said despite his sight “stablising” his central visual field had been ruined beyond repair.
A lack of vitamin B and copper “likely contributed to the patient’s vision and hearing loss”, said Dr Atan.
While his bone weakness was probably caused by not consuming oily fish, cheese and eggs – which contain vitamin D.
Deficiencies in vitamins B1, B2, B3, B6, B9, B12, along with iron, calcium, magnesium, and copper are all known to cause NON.
The boy’s mother said the condition has “devastated his life”, he has dropped out of college due to his impairments and she has given up her job to care for him.
The woman, who did not want to be named, said: “His sight went downhill very fast – to the point where he is now legally blind.
“He has no social life to speak of now. After leaving school he got into college to do a course in IT. But he had to give it up because he could not see or hear anything.
“He would love a job – but he has not been able to find anything he can do. I had to quit my job in a pub. I now look after him full-time.
“He is taking vitamin supplements – but his diet is still pretty much the same.
“When he was having counselling we managed to start him on fruit smoothies. But he’s gone off those now.”