o Carotenoids are found in a large variety of plant products, and beta-carotene is one of these. Research has shown that you can get sufficient amount of vitamin A by eating beta-carotene, but you have to eat more beta-carotene than you have to eat vitamin A - One international unit (IU) is equivalent to 0.3 micrograms of retinol, which is the preformed vitamin A as found in meat, but in order to get the same amount for beta- carotene, you'd have to eat .6 micrograms. What is it good for? - For bone growth, for reproduction, and for the health of the immune system. Important for the appearance of the skin and the mucous membranes they repel bacteria and viruses more effectively when they are healthy. Essential to vision (vision loss if deficient) - Vitamin A deficiency affects many children in the developing world. Not only can it result in blindness, but because of impairment of immune function, it can lead to death, and it's estimated to claim over 600,000 children’s' lives every year, and up to half a million go blind every year. o Golder rice or golden potato can help in underdeveloped countries In smokers, taking large quantities of beta-carotene supplements have actually been shown to increase the risk of lung cancer. - Beta-carotene is an antioxidant Vitamin A, as one finds in meat, on that you can overdose. With an excess of beta-carotene, the worst thing that can happen is that you turn orange.
Vitamin A acid gel, or Retin-A, is effective for a variety of skin blemishes. Taken internally, in a drug, used to be called Accutane, but now it's available as isotretinoin, can be almost magical in clearing up recalcitrant acne. - This is a drug that must not be taken during pregnancy, because it has a very powerful teratogenic effect (affects the embryo in a negative way) Vitamin D Elmer McCollum discovered vitamin D in 1921 when present in food, was capable of preventing a disease known as rickets. - Rickets is a malformation of the bones (first came to light in the industrial revolution in England when children were forced to work in mines) - There was no sunshine and the sky was full of clouds, smoke from all the factories, so there was not much sunshine there either and this resulted in rickets. - Some food could treat rickets such as cod liver oil because it contains vitamin D Why is it called the sunshine vitamin? - Sunshine is a form of radiation. It cannot contain any sort of vitamin. However, it can trigger a host of chemical reactions that take place in the body by which Vitamin D is formed (when the skin is exposed to UVB rays from the sun a chemical reaction occurs that synthesizes vitamin D) A lack of vitamin D can cause: - Rickets - Weak bones (osteoporosis) o This is why dairy products are supplemented with vitamin D Salmon is the best natural source of vitamin D Claims of vitamin D
- Claim that vitamin D reduces respiratory tract infections (i.e. a cold) some research shows that it helps but when you put all the studies and evidence together there is not actual evidence of it helping cannot just trust one research study done.
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- Spring '11
- Nutrition, Vitamin, Unsaturated fat