Common Types of Lettuce
These loose-leaved lettuces grow in large, open heads with a profusion of ruffly, deeply colored fronds; look for crisp leaves with no brown edges. Leaf lettuces have more flavor than head lettuces, and red leaf adds a vibrant splash of bronzy red to a salad. Red is high in vitamin A and other antioxidants. Both red and green are good sources of folate.