Beta-carotene (Salem Health: Cancer)
Cancers treated or prevented: Studies have found that a diet high in fruits and vegetables containing beta-carotene reduces the risk of certain types of cancer, including those of the prostate and lung. Researchers believe that beta-carotene and other antioxidants in fruits and vegetables work together to lower cancer risk.
It was thought that beta-carotene supplements might reduce the risk of certain cancers, especially lung cancer, but there is no evidence of any cancer preventive benefit when beta-carotene is taken alone in supplement form. In fact, studies have found that smokers and people who have been exposed to asbestos who take beta-carotene supplements have a significantly higher risk of developing lung cancer and of dying from their cancer than those who do not take the supplements. In addition, the National Cancer Institute’s Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (1992-2001) found that men with the highest levels of beta-carotene in their blood were at increased risk for developing more aggressive and deadly prostate cancer.
Delivery routes: Oral in capsule and tablet forms. Eating five servings of fruits and vegetables daily provides 6 to 8 milligrams of beta-carotene.
How this substance works: Beta-carotene is an antioxidant. It protects cells and deoxyribonucleic acid (DNA) from damage caused by unstable molecules called free...
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Beta Carotene (Encyclopedia of Alternative Medicine)
Beta carotene is one of the most important naturally occurring antioxidants. It is a fat-soluble pigment found in plants (notably carrots and many colorful vegetables and fruits) and in the sea alga Dunaleilla salina and D. bardawil. Naturalbeta carotene supplements are derived primarily from D. salina. Beta carotene is one of the major dietary carotenoids and one of the most biologically active of approximately 800 carotenes and more than 1,000 carotenoids present in food. It is responsible for the orange or yellow colors of many fruits and vegetables. In the human body, beta carotene is found in lipids and in fat tissues. Sometimes beta carotene is called provitamin A because it is more easily converted to vitamin A (retinol) in the liver than other carotenoids. Beta carotene is considered to be a conditionally essential nutrient because it becomes essential when vitamin A intake is low.
Beta carotene consists of a chain of 40 carbon atoms, with conjugated double bonds and a ring structure at each end of the chain. Depending on the positions of the molecular groups attached to the carbon chain, naturally occurring beta carotene may be:
- All-trans beta-carotene
- 9-cis beta-carotene
- 13-cis beta-carotene, in smaller amounts...
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