Onions are nutrient-dense, meaning they’re low in calories but high in vitamins, fiber, and minerals.

One medium onion Source (110 grams [g]) contains:

Calories: 44
Protein: 1.2 g
Carbs: 10.3 g
Sugar: 4.7 g
Fiber: 1.9 g
Fat: 0.1 g
Potassium: 3.4% of Daily Value (DV)
Vitamin C: 9% of the DV