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Night Blindness is caused by vitamin A deficiency. The Alternate name for it is nyctalopia. It is basically, poor vision at night or in dim light. The outer area of the retina is made up of more rods than cones. The rod cells are the cells that enable us to see in poor illumination. This is the reason why loss of side vision often results in night blindness.
Vitamin A is a fat-soluble vitamin. Vitamin A deficiency is one of the most severe nutritional problems in the world. Many factors contribute to this problem. Some researchers found that dietary vitamin A intake is very low, especially among preschool children. Vitamin A - Food sources Vitamin A comes from animal sources such as eggs and meat, and is present in the form of a precursor called beta-carotene, when manufactured by plants. Vitamin A is found in milk, cheese, cream, liver, kidney, cod and halibut fish oil. All of these sources, except for skim milk that has been fortified with vitamin A, are high in saturated fat and cholesterol. The vegetable sources of beta-carotene are fat and cholesterol free. The body regulates the conversion of beta-carotene to vitamin A, based on the body's needs. Sources of beta-carotene are carrots, pumpkin, sweet potatoes, winter squashes, cantaloupe, pink grapefruit, apricots, broccoli, spinach, and most dark green, leafy vegetables. The more intense the color of a fruit or vegetable, the higher the beta-carotene content. Vitamin A - Functions Vitamin A helps in the formation and maintenance of healthy teeth, skeletal and soft tissue, mucous membranes, and skin. It is also known as retinol, as it generates the pigments that are necessary for the working of the retina. It promotes good vision, especially in dim light. It may also be required for reproduction and lactation. Beta carotene, which has antioxidant properties, is a precursor to vitamin A. Vitamin A - Side Effects Vitamin A deficiency can increase the susceptibility to infectious diseases, as well as cause vision problems (nightblindness). Large doses of vitamin A can be toxic. They can also cause abnormal fetal development in pregnant women. Increased amounts of beta-carotene can turn the color of skin to yellow or orange. The skin color returns to normal once the increased intake of beta-carotene is reduced.
Individuals suffering from night blindness not only see poorly at night, but also require some time for their eyes to adjust from brightly lit areas to dim ones. Contrast vision may also be greatly reduced.
For more information of Night Blidness and its treatment:
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Disclaimer: Any information displayed here is just for educational purposes, and may not be taken as an expert advice and should not be applied in life without consulting your eye doctor/specialist. We here by take no responsiblity of the accuracy of the above content as they have been taken from various sources. |
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