Seagrass is a common class of food that does not possess the efficacy and effectiveness of medicines; however, it contains seaweed acid and a variety of minerals such as iron and phosphorus, among others. Seagrass is a higher angiosperm, a collective name for a large group of plants, and it is the only higher angiosperm that can survive in seawater. Seagrass is different from kelp, which is a lower unicellular algae. Seagrass is rich in nutritional value, containing a large amount of alginate, mannitol and potassium, aluminum, magnesium, iron and iodine and other minerals. According to scientific determination per 100 grams of seaweed contains 8 grams of protein (relatively high protein content in plants), 0.1 grams of fat, carotene 0.57 mg, iron 50 mg (much higher than spinach), phosphorus 216 mg. The iodine content in seaweed is relatively high compared to terrestrial food, and patients with hyperthyroidism, Hashimoto’s thyroiditis and thyroid nodules need to control the amount of food.