(NaturalNews) Onions are allium vegetables. Allium
is Latin for garlic, but this genus also includes onions, leeks, chives and shallots. They are all rich in organosulfur compounds and quercetin.
Sulfur is one of those important compounds that gets too little notice. It is involved in hundreds of metabolic activities and is especially noted for it's contribution toward creating the master antioxidant glutathione, another compound that gets too little notice.
It's considered the master antioxidant because it recycles
other spent antioxidants. Unlike most other dietary antioxidants, glutathione is an endogenous antioxidant.
Glutathione is created internally with a little help from some external friends, especially
sulfur compounds, which need to be ingested to help the liver create it. 
Quercitin is an exogenous antioxidant flavonoid in various fruits and vegetables. Resveratrol from apples, red grapes or red wine are food source examples. Allium veggies, especially onions, are also very high in quercetin.
In addition to the antioxidant properties one expects, quercetin acts like an antihistamine. By stabilizing cells that release histamine, it provides anti-inflammatory protection to help resist heart disease and cancer.
Recently, a few "experts" have spread rumors claiming allium veggies are toxic. Seems similar to the apple and apricot seed scares that filter through the internet now and then.
But there have been several studies to support the health claims of allium veggies.
Five onion health benefits studies
1. A South Korean study, "Onion flesh and onion peel enhance antioxidant status in aged rats," was published in a 2007 Journal of Nutritional Science and Vitaminology
Forty aged rats were divided into different groups. Each group was fed a different extract from either onion meat or skin, and the control group was excluded from any form of onion extract.
After three months, all the onion extract groups had higher antioxidant
levels than the control group. But the onion peel group's antioxidant levels were the highest.
Also, the onion extract groups' brain 8-isoprostane levels, markers for neurological and dementia issues, were significantly reduced compared to the control group. 
2. A rather cruel study on rats was conducted in Japan to determine onion quercetin's protection against the deleterious effects of diesel exhaust particles (DEP) with male reproductive toxicity. It was published in Bioscience, Biotechnology, and Biochemistry
Sparing the details and fast forwarding to the conclusion: "These results clearly indicate alleviative effects of quercetin
and onion against the male reproductive toxicity induced by DEP." 
3. An animal study, rats again, was conducted in Nigeria's University of Ibadan and published in a 2008 Biometals
journal. This research team was curious about protecting against kidney poisoning from cadmium (Cd).
After inducing renal damage and decreased glutathione production with Cd infusions, they fed the rats both onion and garlic extracts and found the renal damage was reversed and glutathione production was restored.
They concluded: "These extracts may, therefore, be useful nutritional option(s) in alleviating Cd-induced renal damage." 
4. A French epidemiological study found that breast cancer risk was reduced among women who ate more onions
and garlic. This study was published originally in a 1998 European Journal of Epidemiology
5. The British Journal of Cancer
in 2004 published an epidemiological study with the dramatic title "Eating garlic and onion: A matter of life or death."
That study looked at 238 patients with prostate cancer compared with 471 male control subjects. It was found that men whose intake of allium vegetables was over 10 grams daily had a statistically significant lowered risk of contracting prostate cancer than those whose intake was below 2.2 grams daily.
Enough research. This author continues consuming raw onion and garlic daily regardless of what toxic alarmist naysayers say.Sources for this article include: