Leek, also known as Yangyang grass, Intestinal washing grass and perennial grass, is sweet, pungent, warm and non-toxic. According to Compendium of Materia Medica, leek has the functions of tonifying kidney and warming yang, benefiting liver and strengthening stomach, promoting circulation of qi and regulating blood, moistening intestines and relaxing bowels, and is mainly used to treat night sweats, enuresis, frequent urination, choking, nausea, diarrhea, abdominal pain, menstrual diseases of women, menstrual leakage, leukorrhagia, traumatic injury, vomiting blood and epistaxis.

The unique fragrance of leek is formed by the sulfide contained in it, which has certain bactericidal and anti-inflammatory effects and helps the human body to improve its immunity. The quality of leek in spring is the best, followed by late autumn and the worst in summer. Chinese medicine experts suggest that you should eat leeks in spring to improve your immunity. Sulfide in leek can also help human body absorb vitamin B 1 and vitamin A, so it is a more nutritious way to eat leek if it is matched with pig meat food rich in vitamin B 1. However, sulfides are volatile when heated, so it is necessary to stir the pot quickly when cooking leeks.