Diindolylmethane is produced through the metabolism of indole-3-carbinol, reports the March 2006 issue of In Vivo." Indole-3-carbinol is found in brassica vegetables such as broccoli, Brussels sprouts, cabbage and cauliflower. According to the University of Nebraska, both indole-3-carbinol and diindolylmethane have a variety of biological effects, including anticancer effects. However, in some animal studies, indole-3-carbinol was found to actually promote tumor development.
Broccoli
Broccoli is a source of diindolylmethane, fiber and various vitamins and minerals. A 2009 study by P. Riso and colleagues from the University of Milan, Italy, investigated the protective effect of 200 g broccoli daily for 10 days. Tests of DNA damage confirmed that broccoli consumption had a protective effect. The effect was even more pronounced in smokers, who tend to have higher than average DNA damage.
Brussels sprouts
Brussels sprouts contain diindolylmethane, fiber, vitamin A and C, and folate. Vitamin A is essential for healthy vision, especially night vision, and is important in the maintenance of the linings of the respiratory, intestinal and urinary tracts. Vitamin C, or ascorbic acid, is an antioxidant, is essential for the production of collagen and in wound healing, and maintains a healthy immune system. Folate is required for DNA synthesis and its deficiency during pregnancy is associated with a higher rate of birth defects, reports the "Manual of Dietetic Practice."
Cabbage
The March 2010 issue of the "Brazilian Journal of Medicinal and Biological Research" reports a rodent study investigating the chemopreventative potential of water extracts of cabbage and kale. The study found that DNA in liver from treated rats was more resistant to damage induced by hydrogen peroxide. Rats given cabbage extract were found to have higher levels of lutein in their livers -- lutein is a caroteinoid with antioxidant properties. On the other hand it was found that rats given the extracts were no less prone to tumor-related lesions of the placenta than unsupplemented rats.
Cauliflower
The cauliflower is another member of the Brassica family that is eaten either raw or cooked. The August 2007 issue of the "Journal of the National Cancer Institute" reports a study which investigated the association between prostate cancer risk and intake of specific fruits and vegetables in 1,338 patients with prostate cancer among 29,361 men. They found that the higher the intake of cruciferous vegetables, in particular broccoli and cauliflower, the lower the risk of aggressive prostate cancer.
References
- "In Vivo"; The natural chemopreventive compound indole-3-carbinol: state of the science; Rogen EG; March 2006;
- "Nutrition and Cancer"; Effect of broccoli intake on markers related to oxidative stress and cancer risk in healthy smokers and nonsmokers; Riso P et al; February 2009
- "Manual of Dietetic Practice, 4th Edition"; T. Briony and J. Bishop; 2007
- "Brazilian Journal of Medicinal and Biological Research"; Water extracts of cabbage and kale inhibit ex vivo H(2)O(2)-induced DNA damage but not rat hepatocarcinogenesis; Horst MA et al; March 2010
- "Journal of the National Cancer Institute"; Prospective study of fruit and vegetable intake and risk of prostate cancer; Kirsh VA et al; August 2007
