Lutein is found in certain fruits and vegetables as well as egg yolks. It 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 beta carotene, 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 apha-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 most 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 diseases.
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 processes. As free radicals travel through the body, they cause damage to cells and genes by stealing electrons from other molecules - a process referred to as oxidation. Test tube studies conducted by the Agricultural Research Service of the United States Department of Agriculture (USDA) suggest that lutein may be just as effective at combating free radicals as vitamin E, which is a potent antioxidant. Concentrated mainly in the lens and retina of the eye, lutein may help to protect vision by neutralizing free radicals and by increasing the density of eye pigment. Lutein may also shield the eyes from the destructive effect of sunlight. In one very small study, published in the journal Experimental Eye Research in 1997, lutein significantly reduced the amount of potentially damaging blue light that reached sensitive tissues in the eye. The study involved two people who received the equivalent of 30 mg of lutein a day for almost five months.
