What are the benefits and effects of mustard greens? How to choose the complete mustard greens? Mustard greens are rich in vitamins, carotene, calcium, potassium, phosphorus, sodium, magnesium and other trace elements. Moderate consumption can replenish the nutrients needed by the human body, improve the body's immunity and enhance the ability to resist diseases. Look at the mustard petiole there is no softening phenomenon, choose the petiole more fat mustard is better.