The onion has about 400 species. About 228 species grow on the territory of Russia. The most common species is a bulb-turnip and feather leaves. The birthplace of onions is Central Asia, Iran and Afghanistan. In Europe, the onion came from the Romans, from which it was learned to cultivate other European nations.
The composition of onion:
Onions are a source of vitamins of group B, C, essential oils and mineral substances such as: calcium, manganese, copper, cobalt, zinc, fluorine, molybdenum, iodine, iron and nickel. Onions are rich in iron. You can get this element from both raw and roasted, baked and stewed onions, especially if used as a side dish to the liver. Another bow is rich in potassium, which has a beneficial effect on the cardiovascular system of man.
Useful properties of onions:
Onion stimulates appetite and improves digestion, improves body tone, antiseptic, antimicrobial, bactericidal, anti-inflammatory, anti-sclerotic and antidiabetic effect. Onion helps to fight low pressure and contains flavonoids that prevent the formation of cancer cells.

List of vitamins:

Systemic thiamine deficiency is a causal factor in the development of a number of serious disorders, the leading place in which the lesions of the nervous system occupy. The complex of consequences of thiamine deficiency is known as the beriberi disease.

Vitamin B2 is necessary for the formation of erythrocytes, antibodies, for the regulation of growth and reproductive functions in the body. It is also necessary for the health of the skin, nails, hair growth and in general for the health of the whole organism, including the function of the thyroid gland.

Vitamin B6 is found in many products. Especially a lot of it is contained in the grain sprouts, walnuts and hazelnuts, spinach, potatoes and carrots, color and cabbage, tomatoes, strawberries, cherries, oranges and lemons, avocados.

Vitamin C is used as a restorative and stimulating immune system for various diseases (colds, oncological, etc.), and also prophylactically with insufficient intake of food, for example, in the winter-spring period.