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Vegetables

Onion

Per serving: 1 cup chopped (160g)

alliumquercetinprebioticlow caloriesulfur compounds
64CALORIES
per serving
1.8gProtein
14.9gCarbs
0.2gFat
2.7gFiber

About Onion

Onions are aromatic vegetables belonging to the Allium family. They are commonly used as a flavor base in soups, curries, salads, sauces and roasted dishes.

They contain quercetin, prebiotic fibers and sulfur-containing compounds. Raw onions have a sharper flavor, while cooking makes them softer and sweeter.

At-a-Glance Stats

10Glycemic Index🟢 Low
1Glycemic Load🟢 Low
89%Water Content💧 Hydrating
12.2gNet CarbsTotal carbs − fiber

Macronutrient Breakdown

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64 kcal

Total calories per 1 cup chopped (160g)

Protein

Builds & repairs muscle tissue

1.8g

4% of typical daily value

Carbohydrates

Primary fuel source for energy

14.9g

15% of typical daily value

Total Fat

Supports hormones & nutrient uptake

0.2g

0% of typical daily value

Dietary Fiber

Feeds gut bacteria & aids digestion

2.7g

9% of typical daily value

Calories by Serving Size

Serving SizeCaloriesFiber
1/4 cup chopped (40g) 160.7g
1/2 cup chopped (80g) 321.4g
1 cup chopped (160g) 642.7g

All values are approximate. Actual nutrition may vary by apple variety (Fuji, Gala, Granny Smith, etc.).

Key Health Benefits

  • 1

    Contains quercetin and sulfur-containing plant compounds with antioxidant activity.

  • 2

    Provides prebiotic fibers that help support beneficial intestinal bacteria.

  • 3

    Adds strong flavor to meals without contributing many calories or fat.

  • 4

    Provides Vitamin C, Vitamin B6, folate and potassium.

Vitamins & Minerals

NutrientAmount% Daily Value
Vitamin C11.8mg
13%
Vitamin B60.19mg
11%
Folate30mcg
8%
Potassium234mg
5%

% Daily Value (2,000 cal diet):

≥20% High10-19% Good<10% Low

Expert Tip

Chopping onions and allowing them to rest for several minutes before cooking helps preserve the activity of their sulfur-containing compounds. Keto diets should use smaller portions because a full cup contains over 12g of net carbohydrates.

Diet Compatibility

VeganVegetarianGluten-FreeKetoPaleoMediterraneanLow-CalorieDiabetic-Friendly

Frequently Asked Questions

How many calories are in Onion?

Onion contains 64 calories per 1 cup chopped (160g). This includes 1.8g protein (7.2 kcal), 14.9g carbohydrates (59.6 kcal), and 0.2g fat (1.8 kcal).

How much protein does Onion have?

Onion provides 1.8g of protein per 1 cup chopped (160g).

Is Onion good for weight loss?

Provides Vitamin C, Vitamin B6, folate and potassium. With 64 calories per serving, it can fit well within a calorie-controlled diet.