You might not recognize it without shrimp and brown sauce, but few vegetables pack more of a nutritional punch than Chinese white cabbage. For fewer calories than in a stick of gum, bok choy delivers a potent vitamin cocktail, including a big dose of rare cancer-fighting nitrogen compounds called indoles, as well as folic acid, iron, beta-carotene, and potassium. Potassium keeps your muscles and nerves healthy while lowering your blood pressure, and research suggests that betacarotene can reduce the risk of both lung and bladder cancers, as well as macular degeneration.