The onion is any of a variety of plants in the genus Allium, specifically Allium cepa. Allium cepa is also known as the "garden onion" or "bulb" onion. Above ground, the onion shows only a single vertical shoot; the bulb grows underground, and is used for energy storage, leading to the possibility of confusion with a tuber, which it is not. It is a close relative to garlic.
Place of origin: The origin of the onion has 5,000 years of history, spread to Egypt in 1000 BC, after the spread to the Mediterranean region, the 16th century spread to America, introduced to Japan the 17th century, early 20th century into China. Onion is widely distributed in China, both north and south of cultivation.
Nutrient: Onion nutritious, it was determined per 100 grams of fresh onions, 88 g moisture content of about 1 to 1.8 grams of protein, fat 0.3 to 0.5 grams, 5-8 grams of carbohydrates, crude fiber 0.5 g, 130 kJ of heat, calcium 12 mg, also contains caffeic acid, sinapic acid, cinnamic acid, citric acid salts, polysaccharides and amino acids.
Dietotherapy function: Onions can stimulate the stomach, intestine and digestive gland secretion, increase appetite, promote digestion, and the onions without fat, the essential oils can reduce cholesterol containing a mixture of sulfur compounds can be used to treat indigestion, loss of appetite, food product within the stop, etc. symptoms.