Shallots are small-sized onions with a mild taste and odour. Onions need no introduction. They are a key ingredient in most recipes and are even consumed raw. They are packed with several health benefits. They help you control cholesterol levels prevent certain type of cancers provide antifungal antibacterial and antiviral protection lower blood pressure manage diabetes soothe nerves and circulation and speed up digestion. You can substitute onions for shallots and vice versa in cooking but the taste may alter. Also regular white and red onions have more nutritional value than shallots and hence it is recommended to use them.