Nutrition facts
Raw onions are very low in calories, with only 40 calories per 3.5 ounces (100 grams).
By fresh weight, they are 89% water, 9% carbs, and 1.7% fiber, with tiny amounts of protein and fat.
The main nutrients in 3.5 ounces (100 grams) of raw onions are (1):
- Calories: 40
- Water: 89%
- Protein: 1.1 grams
- Carbs: 9.3 grams
- Sugar: 4.2 grams
- Fiber: 1.7 grams
- Fat: 0.1 grams
Red and yellow onions are richer in antioxidants than other types. In fact, yellow onions may contain almost 11 times more antioxidants than white onions.