Table of ContentsView AllTable of ContentsBenefits of OnionsForms and VarietiesRaw vs. CookedNutrition FactsHow to Select Onions

Table of ContentsView All

View All

Table of Contents

Benefits of Onions

Forms and Varieties

Raw vs. Cooked

Nutrition Facts

How to Select Onions

Onions (Allium cepa) are a nutritious vegetable of theAlliumgenus, like garlic, chives, leeks, and shallots. They come in different varieties and provide many health benefits, such as antioxidants, protection against cancer, and immune system support. Including onions in your diet is a nutritious way to improve your overall health.This article will provide an overview of the benefits of onions and their nutritious value and offer tips on selecting fresh, safe, and uncontaminated onions.Arx0nt / Getty ImagesBenefits: Why Are Onions Healthy?Onions are considered to be a highly nutritious vegetable. They containphytochemicals, compounds plants produce to ward off harmful bacteria,viruses, and fungi. Consuming these phytochemicals provides health benefits and gives onions the following properties:AntioxidantAntimicrobialAnti-inflammatoryAnti-obesityAntidiabeticAnticancerProtective to the cardiovascular, digestive, respiratory, reproductive, and neurological systemsProtective against liver diseaseSupportive of a healthy immune systemOnions can be used as an herbal medicine to relieve asthma, bronchitis, and coughing.Lung Cancer Fighting FoodsForms and Varieties of OnionsOnions are part of theAlliumplant genus, including plants like garlic, leeks, and chives.They vary in flavor and can be sweet, tangy, and sour. Different varieties combined with farming practices contribute to the flavor profile of onions.There are many varieties of onions. The most common and widely available onions are red, yellow, Spanish (sweet), and white. Other onions includecipollini, pearl, and Vidalia.What’s Healthier, Raw or Cooked Onions?Though onions are beneficial whether eaten raw or cooked, cooking onions reduces the number ofthiosulfinates, compounds that give onions their antimicrobial, antifungal, and antibiotic properties. However, research shows that when onions are crushed before cooking, they retain their health benefits.Of the various cooking methods, boiling and frying onions seem to cause the most significant loss in nutritious value. Other preparation methods that decrease health benefits include sautéing, steaming, and microwaving.In contrast, baking onions is shown to increase theirflavonoidsin onions. Consuming dried, powdered onions can also offer nutritious value to food, especially if the powder is freeze-dried.Onions can be incorporated into a diet in several ways, including cooking, pickling, consuming them raw on sandwiches and salads, turning them into juice, or using them as a spice.Why Chopping Onions Makes Us CryOnion Nutrition FactsOnions are a highly nutritious food that can contribute to a healthy diet. Along with other related vegetables, like garlic, leeks, and shallots, onions contain flavonoids, glutathione, selenium compounds, vitamin E, and vitamin C, which contribute to the antioxidant properties of the vegetable.Here is the nutrition information for a medium onion:Total calories: 44Total fat: 0 grams (g)Cholesterol:0 milligrams (mg)Carbohydrates: 10 gDietary fiber: 2 gTotal sugars: 5 gProtein: 1 gCalcium:2 mgSodium: 4 mgIron: 1 mgVitamin D:0 micrograms (mcg)Though research is variable, some studies show that eating onions can decrease certain cancers, especially those affecting the digestive tract.Signs and Symptoms of Stomach CancerHow to Select Uncontaminated OnionsThough onions have many health benefits, they can contain pesticide residue, heavy metals, microbial contamination, andnitrateaccumulation. Knowing where your onions come from can help ensure there wasn’t incorrect use of pesticides or that the soil the onions were grown in was not enriched with heavy metals. When possible, purchase onions from reputable sources with transparent farming practices, such as at farmers markets.Onions found in environments that have not been effectively sterilized run the risk of growing harmful bacteria. To avoid contamination ofEscherichia. coli(E. coli),salmonella, andmold, it’s safest to purchase whole onions and cut them at home rather than buying pre-chopped onions at the store.When purchasing onions, select those that feel firm, have little to no bruises or discolored spots, and have dry skins. Avoid onions that show evidence of mold, such as white or black spots on the surface or inside the layers of the onion, and those with green shoots, which means the onion is still edible but won’t last as long.SummaryOnions are a nutritious vegetable that have antifungal, antibacterial, anti-inflammatory, and many other healthy properties. They provide health benefits regardless of how they are prepared, though onions lose some of their nutritional value when cooked. Part of what makes onions so healthy is that they contain flavonoids, glutathione, selenium compounds, vitamin E, and vitamin C.The most common types of onions are red, white, yellow, and Spanish onions. When selecting onions, look for those that are without blemishes or discoloration, feel firm, and have dry, papery skins.

Onions (Allium cepa) are a nutritious vegetable of theAlliumgenus, like garlic, chives, leeks, and shallots. They come in different varieties and provide many health benefits, such as antioxidants, protection against cancer, and immune system support. Including onions in your diet is a nutritious way to improve your overall health.

This article will provide an overview of the benefits of onions and their nutritious value and offer tips on selecting fresh, safe, and uncontaminated onions.

Arx0nt / Getty Images

Raw organic onions on linen sackcloth. Summer autumn vegetable harvest, agriculture concept

Benefits: Why Are Onions Healthy?

Onions are considered to be a highly nutritious vegetable. They containphytochemicals, compounds plants produce to ward off harmful bacteria,viruses, and fungi. Consuming these phytochemicals provides health benefits and gives onions the following properties:

Onions can be used as an herbal medicine to relieve asthma, bronchitis, and coughing.

Lung Cancer Fighting Foods

Forms and Varieties of Onions

Onions are part of theAlliumplant genus, including plants like garlic, leeks, and chives.They vary in flavor and can be sweet, tangy, and sour. Different varieties combined with farming practices contribute to the flavor profile of onions.

There are many varieties of onions. The most common and widely available onions are red, yellow, Spanish (sweet), and white. Other onions includecipollini, pearl, and Vidalia.

What’s Healthier, Raw or Cooked Onions?

Though onions are beneficial whether eaten raw or cooked, cooking onions reduces the number ofthiosulfinates, compounds that give onions their antimicrobial, antifungal, and antibiotic properties. However, research shows that when onions are crushed before cooking, they retain their health benefits.

Of the various cooking methods, boiling and frying onions seem to cause the most significant loss in nutritious value. Other preparation methods that decrease health benefits include sautéing, steaming, and microwaving.

In contrast, baking onions is shown to increase theirflavonoidsin onions. Consuming dried, powdered onions can also offer nutritious value to food, especially if the powder is freeze-dried.

Onions can be incorporated into a diet in several ways, including cooking, pickling, consuming them raw on sandwiches and salads, turning them into juice, or using them as a spice.

Why Chopping Onions Makes Us Cry

Onion Nutrition Facts

Onions are a highly nutritious food that can contribute to a healthy diet. Along with other related vegetables, like garlic, leeks, and shallots, onions contain flavonoids, glutathione, selenium compounds, vitamin E, and vitamin C, which contribute to the antioxidant properties of the vegetable.

Here is the nutrition information for a medium onion:

Though research is variable, some studies show that eating onions can decrease certain cancers, especially those affecting the digestive tract.

Signs and Symptoms of Stomach Cancer

How to Select Uncontaminated Onions

Though onions have many health benefits, they can contain pesticide residue, heavy metals, microbial contamination, andnitrateaccumulation. Knowing where your onions come from can help ensure there wasn’t incorrect use of pesticides or that the soil the onions were grown in was not enriched with heavy metals. When possible, purchase onions from reputable sources with transparent farming practices, such as at farmers markets.

Onions found in environments that have not been effectively sterilized run the risk of growing harmful bacteria. To avoid contamination ofEscherichia. coli(E. coli),salmonella, andmold, it’s safest to purchase whole onions and cut them at home rather than buying pre-chopped onions at the store.

When purchasing onions, select those that feel firm, have little to no bruises or discolored spots, and have dry skins. Avoid onions that show evidence of mold, such as white or black spots on the surface or inside the layers of the onion, and those with green shoots, which means the onion is still edible but won’t last as long.

Summary

Onions are a nutritious vegetable that have antifungal, antibacterial, anti-inflammatory, and many other healthy properties. They provide health benefits regardless of how they are prepared, though onions lose some of their nutritional value when cooked. Part of what makes onions so healthy is that they contain flavonoids, glutathione, selenium compounds, vitamin E, and vitamin C.

The most common types of onions are red, white, yellow, and Spanish onions. When selecting onions, look for those that are without blemishes or discoloration, feel firm, and have dry, papery skins.

5 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Zhao XX, Lin FJ, Li H, et al.Recent advances in bioactive compounds, health functions, and safety concerns of onion(Allium cepa L.).Front Nutr.2021;8:669805. doi:10.3389/fnut.2021.669805Oregon State University.Types of onions and varieties.Nicastro HL, Ross SA, Milner JA.Garlic and onions: Their cancer prevention properties.Cancer Prev Res (Phila). 2015;8(3):181-189. doi:10.1158/1940-6207.CAPR-14-0172Kothari D, Lee WD, Kim SK.Allium flavonols: Health benefits, molecular targets, and bioavailability.Antioxidants. 2020;9(9):888. doi:10.3390/antiox9090888U.S. Department of Agriculture.Onions.

5 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Zhao XX, Lin FJ, Li H, et al.Recent advances in bioactive compounds, health functions, and safety concerns of onion(Allium cepa L.).Front Nutr.2021;8:669805. doi:10.3389/fnut.2021.669805Oregon State University.Types of onions and varieties.Nicastro HL, Ross SA, Milner JA.Garlic and onions: Their cancer prevention properties.Cancer Prev Res (Phila). 2015;8(3):181-189. doi:10.1158/1940-6207.CAPR-14-0172Kothari D, Lee WD, Kim SK.Allium flavonols: Health benefits, molecular targets, and bioavailability.Antioxidants. 2020;9(9):888. doi:10.3390/antiox9090888U.S. Department of Agriculture.Onions.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Zhao XX, Lin FJ, Li H, et al.Recent advances in bioactive compounds, health functions, and safety concerns of onion(Allium cepa L.).Front Nutr.2021;8:669805. doi:10.3389/fnut.2021.669805Oregon State University.Types of onions and varieties.Nicastro HL, Ross SA, Milner JA.Garlic and onions: Their cancer prevention properties.Cancer Prev Res (Phila). 2015;8(3):181-189. doi:10.1158/1940-6207.CAPR-14-0172Kothari D, Lee WD, Kim SK.Allium flavonols: Health benefits, molecular targets, and bioavailability.Antioxidants. 2020;9(9):888. doi:10.3390/antiox9090888U.S. Department of Agriculture.Onions.

Zhao XX, Lin FJ, Li H, et al.Recent advances in bioactive compounds, health functions, and safety concerns of onion(Allium cepa L.).Front Nutr.2021;8:669805. doi:10.3389/fnut.2021.669805

Oregon State University.Types of onions and varieties.

Nicastro HL, Ross SA, Milner JA.Garlic and onions: Their cancer prevention properties.Cancer Prev Res (Phila). 2015;8(3):181-189. doi:10.1158/1940-6207.CAPR-14-0172

Kothari D, Lee WD, Kim SK.Allium flavonols: Health benefits, molecular targets, and bioavailability.Antioxidants. 2020;9(9):888. doi:10.3390/antiox9090888

U.S. Department of Agriculture.Onions.

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