Vitamin A deficiency is common in developing countries but rarely seen in developed countries. Approximately 250,000 to 500,000 malnourished children in the developing world go blind each year from a deficiency of vitamin A. Vitamin A for EyesSymptoms of a deficiency of Vitamin A include:
- night blindness (nyctalopia)
- softening of the cornea (keratomalacia).
Also:
- corneal drying (xerosis)
- triangular gray spots on eye (Bitot's spots)
- corneal degeneration and blindness (xerophthalmia)
- impaired immunity, hypokeratosis (white lumps at hair follicles)
Nyctalopia (Greek for "night blindness")This is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, can be caused by injury or a lack of vitamin A.
Individuals suffering from night blindness not only seepoorly at night, but also require some time for their eyes to adjustfrom brightly lit areas to dim ones. Contrast vision may also begreatly reduced.
CarrotsRetinol, or vitamin A, found in fish oils, liver and dairy products. In the Second World War misinformation was spread by the British to cover up the reason for their pilots' successful night time missions. Their success was, in the misinformation, attributed to improved night vision and pilots flying night missions were encouraged to eat plenty of carrots, which contain carotenoids and can be converted into retinol. The actual reason for their success was their use of advanced radar technologies.
The opposite problem, known as hemeralopia, is much rarer.
KeratomalaciaKeratomalacia is an eye disorder that leads to a dry cornea. One of its major causes is a deficiency of Vitamin A.
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