Onion is rich in nutrients. According to the determination, every hundred grams of onion contains protein1~ 2.4g, fat 0.3g, carbohydrate 6 ~ 8.6g, crude fiber 0.5g, calcium/kloc-0.2mg, phosphorus 46mg, iron 0.6mg, carotene/kloc-0.2mg and ascorbic acid/. Green onions contain volatile aromatic substances such as propylene sulfide, which can be used as vegetables and condiments and have good medicinal effects.

Welsh onion has the functions of appetizing, promoting digestion, sterilization and disease prevention, and has been used to treat many diseases in China for a long time. According to Li Shizhen's Compendium of Materia Medica in Ming Dynasty, the stems, roots, leaves, juices and flowers of onion can be used as medicine. Modern medicine believes that green onions have the functions of strengthening the stomach, preventing corrosion, killing germs, stimulating blood circulation, etc., and have a killing effect on Shigella dysenteriae and Staphylococcus.