Sterilization and cold prevention: Onions contain phytoncide such as allicin. These phytoncide have strong bactericidal ability, which can effectively resist influenza virus and prevent colds. Promote digestion: Onions contain allicin, which has a strong aroma and will release a pungent smell when processed. This smell will make people want to cry, but it will also stimulate the secretion of gastric acid and promote gastrointestinal peristalsis, thus promoting digestion and appetite. Cancer prevention: Onion's cancer prevention function comes from its rich quercetin and selenium. Selenium can inhibit the growth and division of human cancer cells, while quercetin can reduce the activity of cancer cells. Lowering blood pressure: Prostaglandin A peculiar to onion is a natural blood thinner. It can dilate human blood vessels and reduce the blood concentration, thus increasing the blood flow of coronary artery and reducing the blood flow of peripheral blood vessels. In addition, it also has the effects of antagonizing pressor substances such as catecholamine, promoting sodium excretion and lowering blood pressure.

2. Nutritional value of onion

Onion was originally produced in Central Asia and West Asia, but because of its high nutritional value, it is planted in the north and south of China. Onion is rich in carotene, vitamin C, selenium, zinc, fiber and other nutrients, and also contains two special nutrients, quercetin and prostaglandin A, which are helpful to prevent cancer, maintain human cardiovascular health, stimulate appetite, promote digestion, sterilize and prevent colds. It can be said that it is very extensive. But because its smell is too exciting, it always makes people love and hate.