The Importance Of Vision Vitamins

By Nita McKinney


Apart from improving eyesight, vision vitamins also play a very vital role in the prevention of certain eye diseases such as macular degeneration and cataracts. Of all the nutrients that are known to have these benefits, vitamin A is undoubtedly the most published. It will be worth noting that there are many other nutritional elements that are equally as helpful. These include, for example, vitamin C and b6 and elements such as selenium, magnesium and zinc. Such nutrients will be found in great quantities in foods such as oranges, leafy vegetables and pumpkins.

We will explore the benefits of vitamin A in more detail since it is the nutrient of greatest significance. The vitamin is involved in the synthesis of a pigment of the retina known as rhodopsin. Rhodopsin is necessary for dim vision. The other important role that this pigment plays is that it helps to keep the cornea moist through the maintenance of the integrity of related membranes.

It is important to mention that vitamin A is made up of several components and is not one unit as is believed by many. The different components are made up of hydrocarbon molecules that are unsaturated. They include molecules such as carotenoids, retinol and retinal. Beta carotene is the most important carotene that has been identified yet. When retinal combines with a protein called opsin, the result is the molecule rhodopsin.

A deficiency in vitamin A may lead to various eye problems ranging from mild, moderate to severe manifestation depending on the chronicity of the deficiency. Lack of this crucial vitamin can either be primary or secondary. A primary deficiency is due inadequate intake of either provitamin A carotenoids (vegetables and fruits) or the preformed vitamin from dairy and animal products. This is the commoner form.

Secondary deficiency may be seen in a number of circumstances. For instance, it is seen when there is malabsorption of the vitamin. This frequently occurs when there is decreased uptake of lipids and reduced release of bile. The vitamin requires fat to dissolve and a deficiency of the fats will therefore result in decreased absorption. Other risk factors for the same include prolonged smoking and alcohol intake.

One of the most initial manifestations of vitamin A deficiency is night blindness. This refers to impaired scotopic vision. With time, the condition may worsen and changes such as drying of the conjunctiva may occur. This happens because the normal tear secreting system is replaced by keratinisation. This is accompanied by formation of keratin plaques in the cornea which eventually gets eroded as more keratinisation leading to complete blindness.

The antioxidant properties of vitamin C help protect the eye from damage due to radiation. This nutrient also helps in maintaining normal pressure, collagen and capillary integrity. Vitamin B6 helps maintain the structure and function of red blood cells found within the retina. A trace element such as zinc plays a key role in ensuring good vision. It is responsible for converting beta carotene to vitamin A.

While it may not be possible to have all these vision vitamins in the diet at all times, it is wise to have them as many times as possible. The factors that determine intake include, among others, pregnancy, lactation, sex and age. It is important to take just enough in each serving to avoid toxicity.




About the Author: