Malnutrition is a condition that results from eating a diet in which one or more nutrients are either not enough or are too much such that the diet causes health problems. It has been a major world crises for decades most especially in Africa. However, there have been several health complications linked to malnutrition such as Kwashiorkor, osteoporosis, rickets etc. but not much has been known that it could also lead to a permanent blindness until a recent study.
The University of Bristol researchers who examined the case of the effect of malnutrition in visions, recommend
clinicians consider nutritional optic neuropathy in any patients with
unexplained vision symptoms and poor diet, regardless of Body mass Index, to avoid
permanent vision loss.
Nutritional optic neuropathy is a
dysfunction of the optic nerve which is important for vision. The
condition is reversible, if treated early. But, when left untreated, it can
cause permanent damage to the optic nerves leading to permanent blindness since the nerves can no longer transmit visual impulse to the brain.
However, In developed countries where food supply is good, 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. But in the developing countries or under developed world, poverty, war and drought are linked to malnutrition and higher rates of nutritional optic neuropathy.
Clinician scientists from Bristol Medical School and the Bristol Eye Hospital in the UK examined the case of a teenage patient who first visited his general practitioner GP complaining of tiredness. The link between his nutritional status and vision was not picked up until much later, and by then, his visual impairment had become permanent.
Aside from being particular about what he eats, the patient had a normal BMI and height and no visible signs of malnutrition and took no medications. Initial tests showed macrocytic 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 vitamin B12 deficiency, low copper and selenium levels, a high zinc level, and markedly reduced vitamin D level and bone mineral density, which are the major culprits of his problem.
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 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 vitamin B12 deficiency.