Radishes are root vegetables with a distinctive flavor that range from the juicy crispness of the familiar red globe radish to the sharp bite of the turnip-shaped black radish. Like their relatives broccoli, cabbage, and kale, radishes are cruciferous vegetables that offer cancer-protecting potential. They were first cultivated thousands of years ago in China, then in Egypt and Greece (where the vegetable was so highly regarded that gold replicas were made of it). As with many other root vegetables, their green tops are edible and lend a peppery taste to salads. While radishes are not nutritionally outstanding, they are a good source of vitamin C. They make a perfect, very low calorie snack food.