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Benefits of Red Onions

Red onions, also known as Spanish onions, contain plenty of healthy essential nutrients as well as phytochemicals that provide long-term health benefits. Including red onions in your daily diet may help reduce your risk of chronic disease. Pungent yet flavorful, red onions can be enjoyed in salads, sliced for use on sandwiches or cooked into soups or other dishes.

A 1/2-cup serving of chopped onion contains only 32 calories and no fat or cholesterol, making it a healthy choice for those watching their fat or calorie intake. A serving also contains 1.5 grams of fiber. Fiber helps improve the functioning of the digestive tract, and it helps prevent constipation. Red onions also contain plenty of vitamins and minerals, including folate, thiamine, calcium, magnesium, potassium, manganese and vitamins C, K and B-6. Consuming foods with a variety of nutrients helps keep the body healthy on a day-to-day basis and may help prevent chronic disease.

Red onions contain compounds called flavonoids, which are the primary source of pigmentation in these vegetables. The most important of these flavonoids is quercetin, an antioxidant compound that may offer protection against cancer, heart disease and allergies. A 2007 study published in the “Journal of Nutrition” found that taking supplemental quercetin reduced blood pressure, and the compound has also been linked to a reduction in the risk of stroke and coronary heart disease. Because dietary flavonoids often operate in synergy with other phytochemicals or nutrients in whole foods, consuming raw red onions can be a better way to increase your quercetin intake than taking supplements.

Other Health Benefits
Red onions contain high levels of organosulphur compounds, which may offer a protective effect against prostate, colorectal and stomach cancers. Another compound found in red onions, onionin A, may reduce inflammation by suppressing the activity of the immune cells that trigger it. The anti-inflammatory effects of red onion may be beneficial for people with allergies, asthma and arthritis.

How you prepare red onions can affect the overall health benefits you derive from them. The flavonoids in an onion are concentrated near the outer layers, so peel as little of the outer skin as possible to reap the most benefits. Cooking red onions can break down some of the nutrients and phytochemicals, but cooking red onions over low heat instead of high heat can reduce nutrient loss.

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