This crunchy cruciferous vegetable is more than the filler that goes with shrimp in brown sauce. “Bok choy is rich in bone-building calcium, as well as vitamins A and C, folic acid, iron, beta-carotene and potassium,” says celebrity trainer Teddy Bass. Potassium keeps your muscles and nerves in check while lowering your blood pressure, and research suggests that beta-carotene can reduce the risk of both lung and bladder cancers, as well as macular degeneration.