Onion, such a common ingredient - how much do you know about its eight major benefits and effects?

Onion, also called bulb onion, round onion, jade onion, onion head, Dutch onion, foreign onion, is one of the most commonly used side ingredients in stir-frying, and is widely cultivated. Besides being a delicious side ingredient, onion also has eight major benefits and effects - do you know them all!

1. Onion growing environment and morphology

1. Suitable growing environment for onion: Onion has strong adaptability to temperature and needs long hours of sunlight; during the growing period it needs sufficient moisture. Onion has strong adaptability to soil, and neutral loam that is fertile, loose and well aerated is preferable; sandy loam easily yields high output, but clay loam produces plump bulbs with good color and good storage quality. Onion roots have weak fertilizer-absorbing ability, so high yields require sufficient nutrient conditions.

2. Main onion producing areas in China: Jinxiang, Yutai, Shanxian and Pingdu in Shandong; Fengxian in Jiangsu; Jiuquan and Wuwei in Gansu; Yuanmou and Dongchuan in Yunnan; Xichang in Sichuan, and other places.

3. Growth morphology of onion: The onion bulb is thick and large, nearly spherical; papery to thinly leathery, with a thick, fleshy inner skin; the leaves are cylindrical, hollow, thickest below the middle, gradually narrowing upward, shorter than the flower scape; the flower scape is stout and can reach up to 1 m in height; the umbel is spherical, with many dense flowers; the pollen is white; the tepals have a green midvein, are oblong-ovate; the filaments are equal in length; the ovary is nearly spherical; the base of the ventral suture has a curtained, sunken honey nectary; it flowers and fruits from May to July. What we commonly use is the underground fruit.

2. Benefits and effects of onion

1. Onion has the effect of dispersing wind-cold, because the onion bulb and leaves contain an oily volatile substance called propylene sulfide, which has a pungent, spicy taste; this substance can resist cold, ward off influenza viruses, and has a strong bactericidal effect;

2. Onion is rich in nutrients and has a pungent smell. It can stimulate the secretion of the stomach, intestines and digestive glands, increase appetite and promote digestion; moreover, onion contains no fat, and its essential oil contains a mixture of sulfur-containing compounds that can lower cholesterol, so it can be used to treat indigestion, loss of appetite, food accumulation and stagnation, and other conditions;

3. Onion is currently the only known source containing prostaglandin A. Prostaglandin A can dilate blood vessels and reduce blood viscosity, thereby lowering blood pressure, reducing peripheral blood vessels and increasing coronary blood flow, and preventing thrombosis. It counteracts pressor substances such as catecholamines in the human body, and can also promote the excretion of sodium salts, thereby lowering blood pressure. Regular consumption has a health-care effect for people with hypertension, hyperlipidemia and cardiovascular and cerebrovascular diseases;

4. Onion has a certain refreshing effect; it can help cells make better use of glucose, while lowering blood sugar and supplying brain cells with heat energy. It is a good dietary vegetable for patients with diabetes and mental lethargy;

5. Onion contains a substance called “quercetin”9, which is one of the most effective natural anti-cancer substances known so far. It can prevent mutations in the body's biochemical mechanisms and control the growth of cancer cells, thus having anti-cancer and cancer-preventing effects;

6. The trace element selenium contained in onion is a very strong antioxidant; it can eliminate free radicals in the body and enhance cell vitality and metabolic capacity, with anti-cancer and anti-aging benefits;

7. Onion also contains a certain amount of calcium. In recent years, Swiss scientists have found that regularly eating onion can increase bone density and help prevent and treat osteoporosis;

8. Onion contains plant bactericides such as allicin, so it has a very strong bactericidal ability. Chewing raw onion can prevent colds.

3. Contraindications of onion

It should not be eaten together with the following foods:

(1) Kelp: Onion contains a large amount of oxalic acid, and kelp is rich in iodine and calcium. Eating large amounts of the two foods together can easily produce stones.

(2) Honey: It is rumored online that eating onion and honey together is bad for the eyes and may even cause blindness in both eyes. Whether true or not, it is better not to eat the two foods together.

(3) Shrimp: Eating large amounts of onion and shrimp together will produce calcium oxalate and cause stones.

(4) Fish: The oxalic acid in onion will decompose and destroy the abundant protein in fish, and produce precipitates, making it harder to digest and absorb.

(5) Soybeans: Eating onion and soybeans together will affect the body's absorption of nutrients in soybeans and reduce the nutritional value of both foods.

The following groups of people should eat less or not eat it:

(1) Patients with digestive diseases such as acute and chronic enteritis and dysentery; patients with cardiovascular diseases such as diabetes, hypertension, hyperlipidemia and arteriosclerosis;

(2) Onion is a "trigger food," so people with pruritic skin diseases, eye diseases, stomach diseases, or inflammation of the lungs and stomach should not eat it or should eat less.

4. Onion price

1. At present, the price of red-skinned onion in Shandong is stable, at 0.15-0.25 yuan/jin;

2. At present, the price of red-skinned onion in Henan is relatively good, at 0.27-0.35 yuan/jin.

Onion cultivation and management costs are relatively low, the yield per mu is high, market demand is large, and the planting prospects are relatively good.