what is the precusor for vitamin A?
457574
One dietary chemical that the body can use as a vitamin A precursor is beta carotene, which comes from orange vegetables (carrots, orange squash).
459529
Too much vitamin A can be harmful or fatal. The body converts the dimerized form, carotene, into vitamin A as it is needed, therefore high levels of carotene are not toxic compared to the ester (animal) forms. The livers of certain animals, especially those adapted to polar environments, often contain amounts of vitamin A that would be toxic to humans. The first documented death due to vitamin A poisoning was 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. Mertz consumed lethal amounts of vitamin A by eating the dogs' livers. The liver of the polar bear also has enough vitamin A to kill a human being, or enough to make even sled dogs very ill.\n\nExcess vitamin A has also been suspected to be a contributor to osteoporosis. This seems to happen at much lower doses than those required to induce acute intoxication. Only preformed vitamin A can cause these problems, because the conversion of carotenoids into vitamin A is downregulated when physiological requirements are met. An excessive uptake of carotenoids can, however, cause carotenosis.\n\nThe carotenoid beta carotene was interestingly associated with an increase in lung cancer when it was studied in a lung cancer prevention trial in male smokers. In non-smokers, the opposite effect has been noted.\n\nAlthough cases of vitamin A toxicity have been reported in arctic explorers and some people taking large doses of synthetic vitamin A for long periods of time, pregnant women require large amounts of vitamin A from preferably natural animal sources, such as liver, raw (non-pasteurized) butter, and cod liver oil. However excess in retinoid form must at all costs be avoided due to its well known teratological effects.
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Vitamins are good for you.
1155659
Hello there\n\nVitamins A & B are found in sweet corn. For more info, check out the link below.
327870
Don't self prescribe vitamin A, you could seriously damage your body or kill yourself.  Acutane is your best choice and is well controled by doctors (I used it and loved it).  PS.  Explores in the artic died after eating polar bear liver because it was so high in vitamin A, so don't be stupid and do it on your own.
2450
I would recommend discussing alternatives with your doctor.\n\nAlthough there are no reports directly linking topical Vitamin A to pregancy problems, it is known that high doses of oral Vitamin A can be harmful.\n\nPlease disregard the opinion above. This cannot be from an ObGyn.
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yes,Ascorbic Acid or Vitamin C(C6H8O6) is a white and crystalline compound.It is of both natural and synthetic origin.
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Vitamin E:  Protects DNA from free radical cell damage.\nPrevents oxidation of LDL cholesterol & protects artery walls.\nEfficiency of heart and circulation.\nIncreases endurance and stamina.\nFights infection, protects against cancer.\nProtects against Alzheimer's & Arthritis.\nHealthy prostate, lungs, & colon.\nProtects against diabetes.\nProtects against dementia.\n\nVitamin A:  Absorption of Vitamin A influences the utilization of other fat-soluble nutrients such as Vitamin E & K.\nAssociated with the health of the inner ear.\nSome studies show a deficiency can cause auditory problems.\n\nVitamin C:  Strengthens immune system.\nDefends against damage to cells from smoke, smog, poor diet, etc.\nSlows aging.\nImproves health of eyes, teeth, gums, skin and bones (build collagen), muscles, blood vessels, and heart.\n\nHope this is useful and feel free to contact me with questions.
30066
D vitamin. And it's also known as a hormone. The vitamin D we eat is transformed in our liver and kidney and then it's secreted through the small intestine in order to absorb calcium, so vitamin D(calcitriol) acts like a transporter.
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It is Vitamin D and u spelled it wrong:Calciferol...I'm sure u can handle it from here
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i don' believe it, 'cause Ascorbic Acid is just another name for the vitamin C, ano it's known as an antioxidant.
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Ascorbic acid is Vit C.  Acidic acid is Vinegar.
1128674
"cretain"? I would just stick with a good multivitamin if I were you. Eat healthy and you shouldn't have to worry too much about "supplements". ~smiles
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I don't know for certain, but my doctor recently told me to steer clear of it because it can overload your body with fat soluble vitamin A.  You can replace it by using flax seed on stuff...baked in bread or ground onto salads etc.
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A ... vitamin A,D,E & K are water soluble vitamins & A,C,E acts as antioxidants in the body
911359
The term vitamin comes from vital amine, which means that yor body needs them . If youare getting a varied diet, you probably do not need to take vitamin pills. Vitamins A,D,E, and K are fat soluble. You can get an overdose with too many vitamin pills. The others are water soluble and you can not overdose. What is important is to get the right number of servings of fruits and vegetables, milk products and meat or meat substitutes to be sure you have the needed vitamins. % servings a day for tose fruits and vegetables. 4 servings of grains, 2 meat and 4 milk.
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http://www.answers.com/topic/vitamin