This post will provide information on "What are the health benefits of onion bulb (Allium cepa)?" as well as provide answers to questions like: When was onion discovered? When did humans first eat onions? Did onions originate from America or Europe? How did the onion get to America? Is eating raw onions good for you? Why are onions bad for you? Is it bad to eat raw onion? What are the side effects of onions?
The onion (Allium cepa L., from Latin cepa "onion"), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus Allium. The shallot is a botanical variety of the onion. Until 2010, the shallot was classified as a separate species.?Its close relatives include the garlic, scallion, leek, chive, and Chinese onion. This genus also contains several other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion (Allium fistulosum), the tree onion (A. proliferum), and the Canada onion (Allium canadense). The name "wild onion" is applied to a number of Allium species, but A. cepa is exclusively known from cultivation. Its ancestral wild original form is not known, although escapes from cultivation have become established in some regions. The onion is most frequently a biennial or a perennial plant, but is usually treated as an annual and harvested in its first growing season. Because the wild onion is extinct and ancient records of using onions span western and eastern Asia, the geographic origin of the onion is uncertain, although domestication likely took place in Southwest or Central Asia. Onions have been variously described as having originated in Iran, western Pakistan and Central Asia. Traces of onions recovered from Bronze Age settlements in China suggest that onions were used as far back as 5000 BC, not only for their flavour, but the bulb's durability in storage and transport. [failed verification] Ancient Egyptians revered the onion bulb, viewing its spherical shape and concentric rings as symbols of eternal life. Onions were used in Egyptian burials, as evidenced by onion traces found in the eye sockets of Ramesses IV. Pliny the Elder of the first century AD wrote about the use of onions and cabbage in Pompeii. He documented Roman beliefs about the onion's ability to improve ocular ailments, aid in sleep, and heal everything from oral sores and toothaches to dog bites, lumbago, and even dysentery. Archaeologists unearthing Pompeii long after its 79 AD volcanic burial have found gardens resembling those in Pliny's detailed narratives. According to texts collected in the fifth/sixth century AD under the authorial aegis of "Apicius" (said to have been a gourmet), onions were used in many Roman recipes. In the Age of Discovery, onions were taken to North America by the first European settlers, only to discover the plant readily available, and in wide use in Native American gastronomy. According to diaries kept by certain first English colonists, the bulb onion was one of the first crops planted by the Pilgrim fathers.
The onion plant has been grown and selectively bred in cultivation for at least 7,000 years. It is a biennial plant, but is usually grown as an annual. Modern varieties typically grow to a height of 15 to 45 cm (6 to 18 in). The leaves are yellowish- to bluish green and grow alternately in a flattened, fan-shaped swathe. They are fleshy, hollow, and cylindrical, with one flattened side. They are at their broadest about a quarter of the way up, beyond which they taper towards a blunt tip. The base of each leaf is a flattened, usually white sheath that grows out of the basal plate of a bulb. From the underside of the plate, a bundle of fibrous roots extends for a short way into the soil. As the onion matures, food reserves begin to accumulate in the leaf bases and the bulb of the onion swells. In the autumn, the leaves die back and the outer scales of the bulb become dry and brittle, so the crop is then normally harvested. If left in the soil over winter, the growing point in the middle of the bulb begins to develop in the spring. New leaves appear and a long, stout, hollow stem expands, topped by a bract protecting a developing inflorescence. The inflorescence takes the form of a globular umbel of white flowers with parts in sixes. The seeds are glossy black and triangular in cross section. The average pH of an onion is around 5.5.
- Onions are low in calories yet high in nutrients, including vitamin C, B vitamins and potassium
- Eating onions may help reduce heart disease risk factors, such as high blood pressure, elevated triglyceride levels and inflammation
- Red onions are rich in anthocyanins, which are powerful plant pigments that may protect against heart disease, certain cancers and diabetes
- Due to the many beneficial compounds found in onions, consuming them may help reduce high blood sugar
- Studies show that onion consumption is associated with improved bone mineral density
- Onions have been shown to inhibit the growth of potentially harmful bacteria like E. coli and S. aureus
- Onions are a rich source of prebiotics, which help boost digestive health, improve bacterial balance in your gut and benefit your immune system
Onions contain compounds called diallyl disulfide and lipid transfer protein, which can cause allergy symptoms like asthma, runny nose, nasal congestion, red eyes, itchy eyes and nose, and contact dermatitis, characterized by a red, itchy rash.