Parboiled Rice, Boiled rice, usuna rice, rice, Parboiled rice is also a source of iron and calcium. Compared to white rice, parboiled rice has fewer calories, fewer carbohydrates, more fiber, and more protein. This makes it a healthier alternative to traditional white rice s calories come from its carbohydrate content. Manganese and Selenium: Boiled rice has manganese and selenium which activate enzymes for good health. Manganese enzymes keep connective tissues strong and help the cells to produce energy. Selenium enzymes promote blood vessel and thyroid gland function