Carotenoids May Protect Against Colon Cancer, Cataracts
BETHESDA, Md.--Carotenoids, found in many fruits and vegetables, may have a chemoprotective role in cancer. In the American Journal of Clinical Nutrition (AJCN), a study looked at carotenoids and their effect on particular types and stages of colon cancer. The dietary carotenoids a-carotene, b-carotene, lycopene, lutein, zeaxanthin and b-cryptoxanthin were then evaluated.
The study population consisted of 1,993 subjects, ranging from 30 to 79 years old, who had been diagnosed with colon cancer, with a control group of 2,410 people without cancer. Participants were asked what foods they had eaten two years prior to their cancer diagnosis. Of the carotenoids studied, lutein proved to have the most protective effect against colon cancer, especially in younger people. Lutein, working with zeaxanthin, another carotenoid, creates an antioxidant which researchers believe scavenges free radicals and reacts with cell membranes that are susceptible to carcinogenesis in the colon.
In other research, lutein may also help combat cataracts. Women who consumed lutein reduced their chances of developing cataracts by 78 percent, whereas men's chances dropped by 81 percent.
The main sources of lutein consumed by participants in the studies included spinach, kale, broccoli, lettuce, tomatoes, carrots, oranges and orange juice, celery and eggs. Researchers recommend consuming at least 6mg of lutein a day.