Mustard greens are packed with energy-boosting, heart-healthy, disease-fighting nutrients. These greens are a delicious source of calcium, magnesium, folic acid and vitamin K, important for bone health. Raw mustard greens have a tasty, peppery bite, but you can mellow it by cooking them. mustasa is also one of the most nutritious vegetables there is. Mostly used in salads and soups, mustasa is the source of the condiment mustard.  They can also be sometimes added in shakes.