Onion vs Red Onion: All Nutritional Differences

Where is more calories, protein, carbs - what is more healthy?

Onion - calories, kcal, weight, nutrition
Red onion - calories, kcal, weight, nutrition

Fact 1: There is More Calories in Onion

At first glance, you can see that in onion is more calories than in red onion.

Onion has 40 kcal per 100g and red onion 33 kcal per 100g so it is pretty easy to calculate that the difference is about 21%.

In onion and in red onion most calories came from carbs.

See tables below to compare onion with red onion in details.

Fact 2: Onion And Red onion Nutrition Difference

Red onion vs Onion: Vitamins and Minerals Comparison

per 100gOnionRed onion
Calories40 33
Carbohydrates9.34 g6.1 g
Fat0.1 g0.4 g
Dietary fiber1.7 g1.7 g
Protein1.1 g1.2 g
Calcium23 mg25 mg
Magnessium10 mg8 mg
Phosphorus29 mg14 mg
Potassium146 mg121 mg
Sodium4 mg6 mg
Zink0.17 mg0.24 mg
Vitaminium B1 (Thiamine)0.046 mg0.03 mg
Vitaminium B2 (riboflavin)0.027 mg0.03 mg
Vitaminium B3 (Niacin)0.116 mg0.2 mg
Vitaminium B60.12 mg0.1 mg
Vitaminium C7.4 mg6 mg
Vitaminium E0.02 mg0.12 mg
Beta karoten1 mg12 mg

Less protein in onion

It is aslo easy to see see that in onion is less protein than in red onion.

There is 1.2g per 100g of red onion and 1.1g per 100g of onion so using simple math we can see that difference is about 9%.

More carbohydrates in onion

In onion is more carbohydrates than in red onion.

There is 6.1g/100g of carbohydrates in red onion and 9.34g/100g in onion so let me do the math for you again - difference is about 53%.

Less fat in onion

In onion is less fats than in red onion.

The tables above show us that there is 0.4g/100g of fats in red onion and 0.1g/100g in onion. In this case difference is about 300%.


  • Calories40
  • Carbohydrates9.34 g
  • Fat0.1 g
  • Dietary fiber1.7 g
  • Protein1.1 g
Onion calories per:
100g | ounce | single piece | slice | cup | sliced

Calories source

  • 88% CARBS.
  • 10% PROTEIN
  • 2% FAT

Red onion

  • Calories33
  • Carbohydrates6.1 g
  • Fat0.4 g
  • Dietary fiber1.7 g
  • Protein1.2 g
Red onion calories per:
100g | ounce | single piece | cup | half cup

Calories source

  • 74% CARBS
  • 15% PROTEIN
  • 11% FAT

Vitamins: red onion vs onion

Minerals: onion vs red onion

Marcin Piotrowicz
Author of this page
Marcin Piotrowicz

calories-info.com creator
Healthy diet and healthy lifestyle promoter

All information about nutrition on this website was created with help of information from the official United States Department of Agriculture database.

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