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Onions

By Shereen Jegtvig, About.com

Updated: June 17, 2007

About.com Health's Disease and Condition content is reviewed by our Medical Review Board

Red Onion

Red Onion

Photo © Carlos Sillero
About Onions:

Onions are a good source of fiber, vitamin C and vitamin B6. Red onions are also a good source of quercetin. Onions also contain organosulfur compounds which help keep blood pressure normal.

Healthy Onion Recipes:

Nutrition Information for Onions:

The following nutrition information is for one serving of onions. That would be one large one-quarter inch thick onion slice, or 38 grams. This general information is for any variety of raw onions.

Macronutrients:

Water: 33.65 g

Calories: 16

Protein: 0.35 g

Carbohydrates: 3.84 g

Fiber: 0.5 g

Sugars: 1.63 g

Total Fat: 0.03 g

Saturated Fat: 0.010 g

Monounsaturated Fat: 0.009 g

Polyunsaturated Fat: 0.024 g

Cholesterol: 0 mg

Micronutrients:

Calcium: 8 mg

Iron: 0.07 mg

Magnesium: 4 mg

Phosphorus: 10 mg

Potassium: 55 mg

Sodium: 1 mg

Zinc: 0.06 mg

Vitamin C: 2.4 mg

Thiamin: 0.018 mg

Riboflavin: 0.010 mg

Niacin: 0.032 mg

Pantothenic Acid: 0.046 mg

Vitamin B6: 0.056 mg

Vitamin B12: 0 mcg

Folate: 7 mcg

Vitamin A: 1 IU

Vitamin E: 0.01 mg

Vitamin K: 0.2 mcg

Phytonutrients:

Phytosterols: 6 mg

beta Carotene: 0 mcg

beta Cryptoxanthin: 0 mcg

Lycopene: 0 mcg

Lutein and Zeaxanthin: 2 mcg

Notes:

Abbreviations:

  • g = gram
  • mg = milligram
  • mcg = microgram
  • IU = International Unit
Nutrient Recommendation Information:

Nutrient Recommendations for Women

Nutrient Recommendations for Men

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  2. Artichokes
  3. Asparagus
  4. Fruits & Vegetables
  5. Nutrition Info - Veggies
  6. Onions

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