Onions

Onions are a globally cultivated vegetable with the botanical name Allium Cepa, cepa itself meaning onion in Latin.

Allium Cepa describes the common “bulb” onion, which comes in a variety of forms. From red and yellow in color, to hard (stronger flavored) or soft(mild/sweet) in texture, and many variations in between. The genus Allium contains many of the bulb onion’s close relatives, several of which are also common cultivars around the world, such as garlic, chives and green onions, shallots and leeks.

Onions have been cultivated for at least 5,000 years, with references to their harvesting and consumption in ancient Persian(Iran), Chinese, Indian, Sumerian and Egyptian texts. To give an idea to their importance in ancient Egypt, for example, the famous Pharaoh Ramses IV, who passed on to his afterlife in 1160 B.C., was entombed with onions in his eye-sockets.

Now onions are cultivated in almost all parts of the world, and are key components of countless traditional diets. They are one of the world’s 10 most cultivated vegetables and the most planted species of the aforementioned Allium genus.

Onions have a wide-ranging flavor profile, depending both on the cultivar and the form of preparation. Cooked onions can often take on sweet flavors (“caramelized”), while raw onions can range in terms of their pungency.

Raw onions (like most fruits and vegetables) contain the highest levels of health benefits.  The largest concentration of phytonutrients such as flavonoids are located in the outer layers of the onion. Onions are typically good sources of vitamin C and B6, as well as dietary fiber, potassium, manganese, biotin and omega 3 fatty acids. The anti-oxidant and anti-inflammatory properties of these compounds and elements likely explain a range of purported health benefits of onions.

Onions have been consistently linked to cardiovascular health, for example, and the low glycemic index of onions suggests an ability to help control blood sugar levels. Research has also shown that ripe onion juice has anti-diabetic properties, and specifically that its consumption can help prevent hyperglycemia in diabetics.

Glycemic Index(raw onion) – 10 = Very Low

Resources and Further Reading

Read more about the history of the onion: 
https://www.onions-usa.org/all-about-onions/history-of-onions

For more information on the health benefits and nutrients contained in onions: 
http://www.whfoods.com/genpage.php?tname=foodspice&dbid=45

A study about ripe onion juice and antihyperglycemic activity: 
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3892491/