Often, the patient consumes about 3–4 times the RDA's specification. Vitamin A acute toxicity occurs when a person ingests vitamin A in large amounts more than the daily recommended value in the threshold of 25,000 IU/kg or more. Mertz may have consumed lethal amounts of vitamin A by eating the dogs' livers. The first documented death possibly caused by vitamin A poisoning was that of Xavier Mertz, a Swiss scientist, who died in January 1913 on an Antarctic expedition that had lost its food supplies and fell to eating its sled dogs. Thus, vitamin A toxicity is typically reported in Arctic explorers and people taking large doses of synthetic vitamin A. The livers of certain animals, especially those adapted to polar environments, such as polar bears and seals, often contain amounts of vitamin A that would be toxic to humans. The body converts the dimerized form, carotene, into vitamin A as it is needed, so high levels of carotene are not toxic, whereas the ester (animal) forms are.
Too much vitamin A in retinoid form can be harmful. In breastfeeding mothers, vitamin A intake should be 1,200 to 1,300 retinol activity units (RAE). The Tolerable Upper Intake Level (UL) for vitamin A, for a 25-year-old man, is 3,000 micrograms/day, or about 10,000 IU. Retinol is also used to reduce the risk of complications in measles patients. In regions where deficiency is common, a single large dose is recommended to those at high risk twice a year. By giving high-doses of vitamin A to the targeted deficient population, a method known as supplementation.It involves addition of synthetic vitamin A to staple foods like margarine, bread, flours, cereals, and infant formula during processing. Enriching commonly eaten and affordable foods with vitamin A, a process called fortification.Through dietary modification involving the adjustment of menu choices of affected persons from available food sources to optimize vitamin A content.Three approaches may be used when populations have low vitamin A levels: Retinol is used to treat vitamin A deficiency.
Retinol is available as a generic medication and over the counter. It is on the World Health Organization's List of Essential Medicines.
Retinol was discovered in 1909, isolated in 1931, and first made in 1947. The body converts retinol to retinal and retinoic acid, through which it acts. High doses during pregnancy may harm the fetus. High doses may cause enlargement of the liver, dry skin, and hypervitaminosis A.
Retinol at normal doses is well tolerated.
DIM SUPPLEMENT SM NATURALS SKIN
As an ingredient in skin-care products, it is used to reduce wrinkles and other effects of skin aging. It is taken by mouth or by injection into a muscle. As a supplement it is used to treat and prevent vitamin A deficiency, especially that which results in xerophthalmia. Dietary sources include fish, dairy products, and meat. Retinol or other forms of vitamin A are needed for vision, cellular development, maintenance of skin and mucous membranes, immune function and reproductive development. Retinol, also called vitamin A 1, is a fat-soluble vitamin in the vitamin A family that is found in food and used as a dietary supplement.
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