Onions are members of the Allium genus of flowering plants that also includes garlic, shallots, leeks and chives. There are so many varieties of onions, and these vegetables contain a variety of vitamins and minerals. In ancient times, onions were used for their medicinal properties to treat ailments such as headaches, heart disease, and mouth sores. The chart below shows some of the health benefits of onions… they also have antibacterial properties and may improve immune function!!