Cabbage is a good source of vitamin K, vitamin C and fiber.  Studies suggest that it, as well as othercruciferous vegetables, may reduce the risk of some cancers, especially those in the colorectal group. This is possibly due to the glucosinolates found in cole crops, which stimulate the production of detoxifying enzymes that remove carcinogens created during metabolism, or due to the sulphoraphane content, also responsible for metabolic anti-carcinogenic activities. Purple cabbage also contains anthocyanins, which in other vegetables have been shown to have anti-carcinogenic properties. Along with other cole crops, cabbage is a source of indole-3-carbinol, a chemical that boosts DNA repair in cells and has been shown—in experiments using cell cultures and animal models—to block the growth of cancer cells. Research suggests that boiling these vegetables reduces their anti-carcinogenic properties.