Onions are a great source for vitamin C. They are used in many wide varieties of recipes. It is used to primarily give food flavor. Onions are a highly used ingredient in various styles of Indian food. They are also cholesterol free and provide many sources of nutrients to your body. Based on a 2000-calorie diet, onions are actually 45 calories per serving. Onions are also low in saturated fat. Onions are believed to create a lower risk of getting cancer. This is created from anti-inflammatory and antioxidant effects that onions create once consumed. They also reduce blood sugar levels and have a chance to improve the health of your bones. 89% of an onion is actually water. They contain very little amounts of protein. Onions also contain the vitamins B9, B6 and some potassium.