Article Contributed on: 8/26/2007 4:05:31 PM
by Dr. Connie Sanchez, ND
The Nutrition Doc
www.TheNutritionDoc.com
For a moment, imagine the life of a green, leafy vegetable growing in your home garden this summer. You'd be planted, stuck in the ground, completely dependent upon the environmental conditions that surround you. If under attack by insects you'd find yourself unable to get up and run away; instead you would have to stay where you were planted, stand your ground, and deal with the situation at hand the best way you could. In order to protect yourself you'd have to devise another means of defense; another way to ward off pesky insects so that you would not end up on their dinner plate tonight.
Scientists have discovered that plants create specific chemicals in which to defend themselves. These chemicals, called phytochemicals (phyto = plant), are contained in the leaves, stems and roots of plants. It seems that the more a plant has been stressed by it's environment the more protective chemicals are formed. It has been discovered that these defensive compounds not only protect the plant making them, but have also been found to protect humans who eat them from various diseases such as cancer.
Current research on cruciferous, or the brassica family of vegetables, such as broccoli, cauliflower, brussels sprouts and cabbage has revealed that these vegetables are especially rich in phytochemicals known as glucosinolates. Glucosinolates are found within the cell walls of these plants.
When we eat a stalk of broccoli, for example, it is mechanically broken down, or crushed, by the chewing action of our teeth and mixed with myrosinase, an enzyme, also found within the cell walls of the plant. When these two compounds mix together as we chew they form potent phytochemicals known as indoles and isothiocyanates. Indoles, especially indole-3-carbinol (I3C), and isothyiocyanates, such as sulphorophane, have very potent anticancer activity and have the ability to induce liver detoxification.
It appears that eating organic (grown without the use of pesticides) vegetables may be the best way to go, as organic vegetables tend to be under more "stress" from their environment than are their nonorganic counterparts.
There is growing evidence that suggests that the more stress a plant undergoes the more they produce these protective phytochemicals.
Foods high in protective phytochemicals known as indoles and isothiocyanates include arugula, broccoli, broccoli sprouts, cauliflower, kale, collard greens, mustard greens, cabbage, brussels spouts, watercress, and turnips.
The National Cancer Institute (NCI) currently recommends eating five or more servings of fruits and vegetables per day.
Based on current evidence of the anticancer effects of cruciferous vegetables it may be wise to include 1-2 servings (serving = 1/2 cup cooked, 1 cup raw) per day of these protective foods to NCI's current dietary recommendations.
References:
1. Higdon JV, et al. Cruciferous vegetables and human cancer risk: epidemiologic evidence and mechanistic basis. Pharmacol Res. 2007 Mar;55(3):224-36. Epub 2007 Jan 25.
2.Guenther PM, et al. Most Americans eat much less than recommended amounts of fruits and vegetables. J Am Diet Assoc. 2006 Sep;106(9):1371-9.
3.Young JE, et al. Phytochemical phenolics in organically grown vegetables. Mol Nutr Food Res. 2005 Dec;49(12):1136-42.
4. Moriarty RM, et al. Organosulfur compounds in cancer chemoprevention. Rev Med Chem. 2007 Aug;7(8):827-38.
5. Minich DM, Bland JS. A review of the clinical efficacy and safety of cruciferous vegetable phytochemicals. Nutr Rev. 2007 Jun;65(6 Pt 1):259-67.