Onion is a very common and cheap home-cooked dish. Its meat is tender, its juice is spicy and light, its quality is good, and it is suitable for raw food. Originated in West Asia, it is cultivated in all parts of China and supplied all the year round. Onion can scavenge oxygen free radicals, enhance metabolism, resist aging and prevent osteoporosis. It is a kind of health food suitable for middle-aged and elderly people.
Onion is rich in nutrition, which not only contains potassium, vitamin C, folic acid, zinc, selenium, fiber and other nutrients, but also contains two special nutrients-quercetin and prostaglandin A. Prostaglandin A contained in onion can reduce peripheral vascular resistance and blood viscosity, and can be used for lowering blood pressure, refreshing, relieving stress and preventing colds.
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The efficacy of onions:
1, cancer prevention: Onion's anticancer effect comes from its rich selenium and quercetin. Selenium is an antioxidant, which can stimulate human immune response, thus inhibiting the division and growth of cancer cells and reducing the toxicity of carcinogens. Quercetin can inhibit the activity of carcinogenic cells and prevent the growth of cancer cells.
2. Maintain cardiovascular health: Onion is the only vegetable known to contain prostaglandin A. Prostaglandin A can dilate blood vessels and reduce blood viscosity, thus lowering blood pressure, increasing coronary blood flow and preventing thrombosis.
Quercetin, which is rich in onion, has high bioavailability. Scientists report that quercetin may help prevent the oxidation of low density lipoprotein (LDL) and provide important protection for atherosclerosis.
3. Stimulate appetite and help digestion: Onions contain allicin, which has a strong aroma and often makes people cry because of its pungent smell during processing. It is this special smell that can stimulate gastric acid secretion and increase appetite. Animal experiments have also proved that onion can improve gastrointestinal tension and promote gastrointestinal peristalsis, thus playing an appetizing role, and has obvious curative effect on anorexia caused by atrophic gastritis, insufficient gastric motility and dyspepsia.
4, sterilization, anti-cold: Onions contain phytoncide such as allicin, which has a strong bactericidal ability and can effectively resist influenza virus and prevent colds. When this phytoncide is excreted from the body through respiratory tract, urinary tract and sweat gland, it can stimulate the secretion of cell wall in these parts, so it has expectorant, diuretic, sweating, bacteriostatic and antibacterial effects.
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