Mayo Clinic Health Oasis
Cruciferous (krew-SIH-fer-uhs) is the scientific name for a group of plants whose four petal flowers resemble a cross. These vegetables are a part of the cabbage family and include arugula, bok choy, broccoli, broccoli sprouts, Brussels sprouts, cabbage, cauliflower, Swiss chard, collards, kale, kohlrabi, mustard greens, radishes, rutabaga, turnips, turnip greens and watercress.
About 20 years ago, epidemiologic studies found that consumption of this group of vegetables was associated with decreased risk for cancer. In the early 1990s, two organic compounds in cruciferous vegetables containing sulfur (dithiolthiones and isothiocyanates) were found to increase the activity of enzymes involved in detoxifying some carcinogens. In addition, a compound called indol-3-carbinol was found to affect estrogen metabolism and is thought to be protective against estrogen-related cancers such as cancer of the breast and uterus. Other beneficial substances found in cruciferous vegetables include fiber and the antioxidants vitamin C and beta carotene.
The chemical composition of this group of vegetables is complex, making it difficult to isolate which compound or group of compounds provides benefit. For now, the strongest evidence indicates that individuals who eat five servings of fruits and vegetables - including cruciferous vegetables - daily cut their risk for cancer by half when compared to those who consume one serving or less. There is a wide choice of cruciferous vegetables. Eat plenty.