Onions Nutrition Facts

40 calories per 100g serving

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Onions are a foundational cooking vegetable at 40 cal/100g, providing subtle sweetness when caramelized and sharp flavor when raw. They contain quercetin, an antioxidant studied for anti-inflammatory properties.

Protein

1.1g

11% of calories

Carbs

9.34g

93% of calories

Fat

0.1g

2% of calories

Nutrition Facts

Per 100g (100g)

NutrientAmount
Calories40 kcal
Protein1.1g
Total Carbohydrates9.34g
Total Fat0.1g
Dietary Fiber1.7g
Sugars4.24g
Saturated Fat0.04g
Cholesterol0mg
Sodium4mg
Potassium146mg
Vitamin A0mcg
Vitamin C7.4mg
Calcium23mg
Iron0.21mg

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Onions for Your Goal

Weight Loss

Add massive flavor for minimal calories. Caramelized onions make simple proteins taste gourmet without sauces or dressings.

Muscle Gain

Not a macro source but essential for making meal prep delicious. Well-seasoned food is easier to eat consistently — onions are the secret to tasty chicken and rice.

Maintenance

A kitchen essential that forms the base of countless cuisines worldwide. Keep yellow, red, and green onions stocked for different applications.

Meal Ideas with Onions

French onion soup + gruyère toast350 cal · 12g protein
Caramelized onion burger + sweet potato fries550 cal · 28g protein
Onion stir-fry + beef + broccoli + rice450 cal · 26g protein

Did you know?

The sulfur compounds that make you cry when cutting onions are actually a defense mechanism the plant evolved to deter animals. Chilling onions before cutting reduces the volatile gas released.

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Common Questions About Onions

How many calories are in Onions?

Onions contains 40 calories per 100g serving. It provides 1.1g of protein, 9.34g of carbs, and 0.1g of fat.

Is Onions good for weight loss?

Add massive flavor for minimal calories. Caramelized onions make simple proteins taste gourmet without sauces or dressings.

What pairs well with Onions?

Great pairings include: French onion soup + gruyère toast, Caramelized onion burger + sweet potato fries, Onion stir-fry + beef + broccoli + rice. These combinations provide a balanced mix of macronutrients.

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