Vitamin A deficiency exists when the chronic failure to eat sufficient amounts of vitamin A or beta-carotene results in levels of blood-serum vitamin A that are below a defined range. Beta-carotene is a form of pre-vitamin A, which is readily converted to vitamin A in the body. Night blindness is the first symptom of vitamin A deficiency. Prolonged and severe vitamin A deficiency can produce total and irreversible blindness. Abnormal visual adaptation to darkness, dry skin, dry hair, broken fingernails, and decreased resistance to infections are among the first signs of vitamin A deficiency
Because vitamin A is an important component for normal vision, vitamin A deficiency will cause night-blindness, or a decreased ability to see in dim light. Another symptom of vitamin A deficiency is a diminished immune system function, which means your body will have difficulty fighting infections.
Vitamin A deficiency is more likely to result from inflammatory diseases that damage the digestive tract and prevent the absorption of vitamin A, such as Crohn’s disease and celiac disease. Alcoholism, zinc deficiency, and pancreatic diseases can also affect the amount of vitamin A in the body.
Vitamin A is actually a group of natural compounds that your body needs for clear vision, healthy bones and skin, normal cell division and differentiation, and reproduction. Vitamin A also helps your body’s immune system fight off infections.
The recommended dietary allowance (RDA) for vitamin A is 1.0 mg/day for the adult man and 0.8 mg/day for the adult woman. Since beta-carotene is converted to vitamin A in the body, the body’s requirement for vitamin A can be supplied entirely by beta-carotene. Six mg of beta-carotene are considered to be the equivalent of 1 mg of vitamin A. The best sources of vitamin A are eggs, milk, butter, liver, and fish, such as herring, sardines, and tuna. Beef is a poor source of vitamin A. Plants do not contain vitamin A, but they do contain beta-carotene and other carotenoids. The best sources of beta-carotene are dark-green, orange, and yellow vegetables; spinach, carrots, oranges, and sweet potatoes are excellent examples. Cereals are poor sources of beta-carotene.
Vitamin A is used for two functions in the body. Used in the eye, it is a component of the eye’s light-sensitive parts, containing rods and cones, that allow for night-vision or for seeing in dim-light circumstances. Vitamin A (retinol) occurs in the rods. Another form of Vitamin A, retinoic acid, is used in the body for regulating the development of various tissues, such as the cells of the skin, and the lining of the lungs and intestines. Vitamin A is important during embryological development, since, without vitamin A, the fertilized egg cannot develop into a fetus.
There are necessarily three Forms of vitamin A. One is retinol which is the most active form and found in the source of animal food. Other form Beta carotene is known as provitamin a and found in the plant source of retinol from which mammals gain two-thirds of their vitamin a. Carotenoids are the largest group among the three and exist in free alcohol.
In the human body retinol is a powerful form. Retinol- binding protein regulates the absorption and metabolism of vitamin A and helps to bind vitamin a. Vitamin a is essential For the growth of bone, for vision, especially in dark adaption, reproduction, cell growth and repair, urinary, for the maintenance of the eyes surface lines, immune response, and intestinal tracts. Vitamin A is also vital for the regulation of adult genes.
Primarily the vitamin A deficiency happened when people eat rice which has not contain the carotene. And this also occurs when protein –energy is absent in daily food.
Secondarily for the deficiency of vitamin A the celiac disease, cirrhosis, giardiasis, tropical sprue, cystic fibrosis, and other pancreatic disease has occurred.
Vitamin A deficiency occurs with the chronic consumption of diets that are deficient in both vitamin A and beta-carotene. When vitamin A deficiency exists in the developed world, it tends to happen in alcoholics or in people with diseases that affect the intestine’s ability to absorb fat. Examples of such diseases are celiac disease (chronic nutritional disorder), cystic fibrosis, and cholestasis (bile-flow failure or interference).
Other problems that happen for vitamin A deficiency are inflammatory bowel disease; fat malabsorption; pancreatic insufficiency; vegan diet; alcoholism; following small-bowel bypass surgery.
If you have vitamin A deficiency symptoms, you need to see a health care provider who can order blood tests to determine if a vitamin A deficiency is the problem or if there are other causes. Vitamin A status is measured by tests for retinol. Blood-serum retinol concentrations of 30-60 mg/dl are considered in the normal range. Levels that fall below this range indicate vitamin A deficiency. Night blindness is measured by a technique called electroretinography. Xerophthalmia, keratomalacia, and Bitot’s spots are diagnosed visually by trained medical personnel.
The prognosis for correcting night blindness is excellent. Xerophthalmia can be corrected with vitamin A therapy.
Vitamin A deficiency can be prevented by including foods rich in vitamin A or beta-carotene as a regular component of the diet; liver, meat, eggs, milk, and dairy products are examples. Foods rich in beta-carotene include red peppers, carrots, pumpkins, as well as those just mentioned. Margarine is rich in beta-carotene because this chemical is used as a coloring agent in margarine production.
Unfortunately, not all of us meet our daily requirements due to inadequate diets or as a result of a medical condition. Either way, a Multivitamin for Men supplement is important to match up to what your body needs to function properly.
A daily Multivitamin for Men supplementation provides the required consumption of many micronutrients that may not be enough in our diet and help to prevent vitamin A deficiency.