Lutein (Salem Health: Cancer)
Cancers treated or prevented: Prostate, breast, colon, lung, and ovarian cancers
Delivery routes: Oral via food or dietary supplements. The most significant food sources for lutein are broccoli, brussels sprouts, collards, kale, peas, pumpkin, spinach, turnip, mustard and dandelion greens, summer and winter squash, and sweet yellow corn. Egg yolks contain a more quickly absorbed form of lutein. Lutein absorption is increased from the intestine when combined with a dietary fat source, such as oil or margarine.
How this substance works: Lutein is chemically similar to the micronutrient zeaxanthin, and they often work together to provide protective benefits. Lutein, also known as a non-provitamin A carotenoid, cannot convert into vitamin A when needed by the body. Most studies find that lutein protects the eyes from disease, such as age-related macular degeneration and cataracts. Some studies find lutein effective against cancer because it decreases the growth of blood vessels to cancerous tumors, increases cancer cell destruction, and improves cell deoxyribonucleic acid (DNA) repair. Overall study results are mixed, however, with one study showing lutein reduced prostate cancer by 25 percent (and as much as 32 percent when combined with the carotenoid lycopene) and another showing an increase in stomach cancer. In general, most studies find that lutein provides some protection against...
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Lutein (Encyclopedia of Alternative Medicine)
Found in certain fruits and vegetables as well as egg yolks, lutein is a nutrient with a number of potentially beneficial effects. It is a member of the carotenoid family, a group of chemicals related to vitamin A. While betacarotene, the precursor of vitamin A, may be the most familiar carotenoid, there are almost 600 others whose effects have yet to be extensively studied. Aside from lutein, these include alpha-carotene, lycopene, zeaxanthin, and beta-cryptoxanthin. In the plant world, carotenoids like lutein help to give color to sweet potatoes, carrots, and other fruits and vegetables. In people, lutein and zeaxanthin make up most of the pigment in the center of the retina, where vision sensitivity is greatest. While lutein is not considered an essential nutrient, studies suggest that it may play an important role in maintaining healthy vision and preventing eye diseases such as age-related macular degeneration (ARMD) and cataracts. Getting adequate amounts of this carotenoid may also decrease the risk of developing colon cancer and heart disease.
Lutein and other carotenoids are considered important because of their antioxidant properties. Antioxidants help to protect cells from damage caused by free radicals, the destructive fragments of oxygen produced as a byproduct during normal metabolic...
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