Updated 4 January 2024
Common names
- Onion, bulb onion, common onion
Common origins
- Native to Western Asia, cultivated throughout the world, Europe
Botanical classification
- Kingdom: Plantae
- Division: Magnoliophyta
- Class: Liliopsida
- Order: Liliales
- Family: Liliaceae
- Genus: Allium
Components
- Essential oil rich in sulphur compounds
- Flavonoids: quercetin
- Plant insulin: glucokinin
- Calcium phosphate, sodium and potassium salts
- Vitamins A, B and C
- Inulin
- Prostaglandins
Parts used
- The whole onion: bulb, onion peel,...
Organoleptic properties
- Odour: characteristic, strong
- Taste: characteristic, strong
Properties
Internal use- Diuretic, facilitates excretion of urea and chlorides
- Skin purifier
- Hypoglycaemic
- Hypolipidaemic
- Cholagogue and choleretic
- Carminative
- Laxative
- Antiseptic
- Vermifuge
- Improves the quality of the intestinal flora
- Decongestant for the pelvis
- Blood pressure regulator
- Blood thinner, platelet aggregation inhibitor and fibrinolytic
- Emmenagogue
- Physical and sexual stimulant
- Antibacterial
- Vulnerable
Indications
Internal use
ENT infections:
Prevention of metabolic syndrome:
- Hyperglycaemia (adjuvant in type II diabetes)
- Prevention of cardiovascular diseases and thrombosis
- Hyperlipidaemia (inhibits LDL oxidation)
- Obesity
Digestive disorders:
Urinary tract diseases:
- Cystitis, especially recurrent cystitis
- Kidney problems
Other indications:
- Premenstrual syndrome (weight gain, breast swelling)
- Lack of physical or sexual vitality
External use
Skin disorders:
Other indications:
Precautions / Contraindications
- It may cause digestive problems (due to the presence of irritating disulphides), but this should not stop the treatment, as it is a "curative crisis" that precedes an improvement in the condition. If necessary, the dosage can be reviewed and the galenic form adapted.
How to use / Current dose
Internal use
- The onion is eaten raw or lightly cooked if the stomach is sensitive.
- In syrup: for ENT disorders.
- Boiled in milk: for ENT and digestive disorders.
- As a tincture or liquid extract: to strengthen the body and stimulate the respiratory and digestive systems. - As dry extract
- In essential oil
External use
- Onion compresses: fresh to relieve pain associated with haemorrhoids and cooked for skin disorders (with a little olive oil for burns).
Find out more
- As soon as onions are cut, the sulphoxides they contain, formed from cysteine, are converted into disulphides, highly irritating compounds responsible for the watery eyes they cause when peeled and cut...
Additional information
Habitat and botanical description
The onion has a stem reduced to an underground bulb (a waterlogged reserve) with several layers of leaves and short, shaggy roots. In the summer of the second year, the stem rises and becomes hollow, round and conical. At the top it bears a spherical umbel of tiny white or pink flowers. Thanks to the sulphur, it sends its seeds into the dry, towards the light.
Harvest time
Harvesting times vary depending on the variety. White onions are harvested earliest, usually in May, before they are fully ripe. Winter varieties are harvested when the above-ground parts have dried out.
It thrives in light, sandy soils with little clay and likes sunny locations. It grows in temperate areas.
Mythology / History / Anecdotes and traditional virtues
Probably originating in western Asia, it has been cultivated and eaten as a vegetable all over the world for several thousand years. Medicinally, Hippocrates, Dioscorides and Pliny appreciated its diuretic properties. Hildegarde de Bingen advised people with weak stomachs not to eat onions because of the moist heat of raw onions. In the Middle Ages, it was recommended for people with "cold complexions, in whom it provokes urine and gives a healthy stomach". Along with shallots and garlic, it was considered by Arab doctors to be a great aphrodisiac. Its juice was also recommended for baldness, and poultices were used to relieve pain.
In the Middle Ages it was also thought to ward off disease, and bunches of onions were hung on the doors of houses. It was also associated with courage, strength and intelligence.
In France, after a night of partying, it's customary to eat onion soup in the morning to ward off a hangover.