calories in a raw onion
Onions are very low in calories and carbohydrate, which is a bonus because a little bit of onion goes a long way. *Based on a 2,000 calorie diet. One medium slice of raw onion contains only 6 calories and 1.3 grams of carbohydrate, making it a very low calorie and almost carbohydrate free food choice. As with any food, the portion will affect the calorie and carbohydrate content. For example, if you are consuming a larger portion of onions, let's say 1/2 cup raw, you'll still consume very little calories, about 21 calories and 5 grams of carbohydrate. This makes onions a great ingredient to use in cooking, adding flavor and volume to meals.