Onions are vegetables, which have the scientific classification of Allium cepa. They contain a number of antioxidant compounds that are very effective in neutralizing the free radicals present in the human body. They have been used for medicinal purposes for millennia.
Onions have been one of the staple plants in the diet of humans for more than 7,000 years, and during much of that time, they were cultivated. There are still wild species in certain areas of Asia, but overall, onions are a globally grown and cultivated plant. Throughout history, they were worshiped by certain cultures, like the Egyptians, who buried them with their pharaoh. This fascination with onions could have stemmed from their versatility and availability or from the medicinal and beneficial properties they have.