In late 1997, researchers at Johns Hopkins School of Medicine in Baltimore discovered that 3-day-old sprouts of certain broccoli varieties contained 20 to 50 times the level of a potent anticancer compound found in mature forms of many cruciferous (cabbage, turnip, and mustard family) vegetables. The research showed that while levels of the compound, sulforaphane, varied greatly among mature broccoli, levels in some broccoli sprouts were comparatively consistent and significantly higher. (Sulforaphane is a phytochemical, one of many compounds plants make for their own benefit.) For their work, the researchers used untreated seed from about 50 varieties of broccoli and found 8 that produced sulforaphane-rich sprouts. 'Saga', a common heat-tolerant broccoli, proved to be an important variety for testing because it produced consistent results.
Anticipating the excitement this discovery would cause, Johns Hopkins School of Medicine was granted a patent for the method of harvesting cruciferous sprouts with high concentrations of sulforaphane at the cotyledon stage, before true leaves emerge. (This patent is being challenged by sprout growers, because sprouting is a process that occurs in nature.)
Some of the researchers have now joined with a licensee of Green Giant Fresh to produce and sell these patented sprouts as a dietary supplement -- the first vegetable ever sold for this purpose.
Although sprouts from plants other than cruciferous vegetables undoubtedly contain phytochemicals -- potentially very beneficial ones -- those compounds haven't been identified yet. Beyond phytochemicals, sprouts offer many nutritional benefits. They are low in calories, free of cholesterol, and virtually free of fat and sodium as well. And they contain a myriad of vitamins and minerals, especially vitamins A and C, protein, and fiber. A 1/4-cup serving of green-leaved sprouts, such as alfalfa, broccoli, or kale, contains 10 to 20 times more vitamin A than any legume sprouts, is high in vitamin C, and contains only about 5 calories. A 3-ounce serving of bean sprouts, such as mung, kidney, or soy, contains 15 to 20 calories, 14 percent of the daily value for fiber, and a significant portion of the folic acid.
Karen C. Duester, a registered dietitian, lives in San Diego, California.
Photography by National Gardening Association