Onions are the second most valuable vegetable after the potato, considering its world production. It has been used in many dishes around the world, for centuries. Allium cepa or just onion is in the same family (Allium) as garlic, chives, shallots or leeks. There are more than 600 different Allium plants, and they all have important role in medicine, as vegetable or spices. Onions might be used raw, cooked, dried or roasted, and it would still contain the same amount of good ingredients.
The plant is rich in sulfur compounds, such as sulfides, sulfoxides, and thiosulfinates. Sulfoxides are responsible for the crying part (eye irritation), when chopping onions and the thiosulfinates have anti-microbial activity.
Benefits of the onion are seen after the long term use of this vegetable. It is useful in many lung problems, easing the condition of asthmatics. It protects the stomach from infections and decreases the risks of stomach cancers. The onion is containing a quarter of the sulfur components of garlic and because of that it has a lower effectiveness.The WHO (World Health Organization) recommends onions for atherosclerosis prevention, appetite loss, and also cold, asthma and bronchitis treatments. In the Eastern medicine, onions are believed to heal bacterial infections, breathing problems and angina.Onions are also use to repel the insects. Fructoligosaccharides in the onions prevent the bacterial infections of the colon and reduce the potential risks of colon cancer. Onion is considered especially active against Bacillus subtilis, Salmonella, and Escherichia coli. Onions and other Allium species are used to treat stomach cancers. Antioxidant and anti-proliferative properties of the onion compounds are responsible for this effect. The best US (United States) varieties are proven to be western yellow, northern red and New York bold onions, because of the highest amount of antioxidants substances. Studies revealed that people eating onions all their life, at least one and a half a day, are less likely to develop the colon cancer. It is recommended to use the stronger flavored onions, since they are the richest in anti-cancerous compounds.
Most people are safe to use onions any time. Be aware that large amounts of onion may cause gastrointestinal (stomach) irritation and problems and lead to nausea and sometimes diarrhea.
Onion has a potential to decrease the risk of heart problems, because it decrease the risks of blood clots. Be careful if you are using blood thinners (anticoagulant medications). Onion might increase the effects of the medicine you have been taking, so consult your doctor about the onions in your diet.