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Vitamin A is an important, fat- soluble vitamin that is made up of several compounds. It occurs in two forms. The first form is called retinol and occurs in foods of animal origin. The second form is called carotene and occurs in foods of both plant and animal origin. Thus the vitamin can be produced internally using the body’s supply of beta carotenes. For a vitamin A supplement, beta carotene is the recommended form in which to take the vitamin This vitamin is used for many vital functions. It is needed for growth and bone development, helps the respiratory system resist infection, aids the immune system and promotes healthy hair, teeth, skin and gums. As an antioxidant, it is effective in combating free radicals, those loose molecules that race through the blood stream and create oxidation, potentially leading to heart disease and other problems. Additionally, the vitamin has even been shown to be effective in regulating insulin levels for people with diabetes. Vitamin A’s most notable use, of course, has been the outstanding benefits it provides to eyesight, particularly night vision. Thousands of years ago, foods rich in this vitamin were shown to bring a certain measure of relief from “night blindness.” The ancient Egyptians used to prepare juice from animal livers (where the vitamin is found in abundance) and poured it onto the eyes of those with poor vision, bringing demonstrable results. It is found in greatest abundance in foods such as cod-liver oil, butterfat in milk, butter and egg yolk. In its beta carotene form it is found most abundantly in green such as leafy vegetables, carrots and sweet potatoes. A deficiency of Vitamin A is one the biggest contributors to night blindness in children. For pregnant women a deficiency may even increase the risk of infant mortality. Deficiencies are more common in developing countries than in the United States, but when they do occur in the U.S., they usually have to do with strict reductions in diet and excessive alcohol consumption. Toxicity, on the other hand, can also occur because this vitamin is stored in the liver. Symptoms that adults are toxic include dry skin and hair, broken fingernails The recommended daily allowance of this important vitamin is around 4,000 IU for males and 5,000 IU for females. 2011-06-13
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