An extreme case of "fussy" or "picky" eating caused a young patient's blindness, according to a new case report.
Nutritional optic neuropathy is a condition of the optic nerve which is reversible if caught early. But, left untreated, it can lead to permanent structural damage to the optic nerve and blindness.
In developed countries like the UK, the most common causes of nutritional optic neuropathy are bowel problems or drugs that interfere with the absorption of various important nutrients from the stomach. Purely dietary causes are less common because food supply is good, but elsewhere in the world, poverty, war, and drought are linked to malnutrition and higher rates of nutritional optic neuropathy.
Scientists from Bristol Medical School examined the case of a teenage patient who first visited his GP complaining of tiredness. Aside from being a "fussy eater," the patient had a normal BMI and height and no visible signs of malnutrition and took no medications.
Initial tests showed anemia and low vitamin B12 levels, which were treated with vitamin B12 injections and dietary advice. When the patient visited the GP a year later, hearing loss and vision symptoms had developed, but no cause was found. By age 17, the patient's vision had progressively worsened, to the point of blindness.
Further investigation found the patient had a vitamin B12 deficiency, low copper and selenium levels, a high zinc level, and markedly reduced vitamin D level and bone mineral density. Since starting secondary school, the patient had consumed a limited diet of chips, crisps, white bread, and some processed pork. By the time the patient's condition was diagnosed, the patient had permanently impaired vision.
The researchers concluded that the patient's 'junk food' diet and limited intake of nutritional vitamins and minerals resulted in the onset of nutritional optic neuropathy.
They suggest the condition could become more prevalent in the future, given the widespread consumption of 'junk food' at the expense of more nutritious options, and the rising popularity of veganism if the vegan diet is not supplemented appropriately to prevent the vitamin B12 deficiency.
Good vision is important for all aspects of our daily life. This case highlights the impact of diet on visual and physical health, and the fact that calorie intake and BMI are not reliable indicators of nutritional status."
Article written by
Mr K.Lakhani BSC MCOptom Dip Tp Ip