Onions 101: Nutrition Facts and Health Effects

Onion Nutrition Facts and Health Effects

The nutritional value of onions are very good. They have high amounts of vitamins A, C, E, K and minerals such as iron, copper and manganese. White onions contain less nutrients than yellow or green ones but they provide some beneficial effects.

Vitamin A is essential for eye sight; it helps protect against cataracts and macular degeneration (AMD). Vitamin B1 is required for proper nerve function and normal growth and development; it prevents rickets and other diseases of bones. Vitamin B2 supports immune system functions, including fighting infections. Vitamin B3 protects against heart disease, cancer, diabetes mellitus, osteoporosis and many other illnesses. Vitamin C promotes healthy skin cells and helps prevent sunburns.

Magnesium plays an important role in blood pressure regulation; it lowers blood sugar levels when needed. Potassium helps regulate body fluids, especially urine output. Iron is necessary for normal muscle contraction and energy production; it strengthens bones and muscles.

In addition to these nutrients, onions are rich in fiber which may help with weight loss. Fats found in onions are mostly monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and saturated fats (SFA); they reduce cholesterol levels in the blood. They also lower triglyceride levels. Furocoumarins (a major phototoxic agent found in allium vegetables such as garlic and onions) is used in some cancer treatments.

Onion contains all the amino acids needed for the human body, although they are present in smaller amounts. Yellow onions are an excellent source of chromium, a trace element that helps control blood sugar levels and is useful for people with diabetes. They also contain good amount of magnesium, a mineral that is required for more than three hundred chemical reactions in the body. It keeps the heart rhythm normal and also allows nerves to fire normally.

It is important to note that too much onions can cause mild stomach problems such as gas and heartburn. The effect is especially felt by individuals suffering from gastrointestinal conditions such as ulcers and kidney diseases. Also, people who have diabetes are advised to monitor blood sugar levels regularly after consuming onions as it can cause a rapid increase.

The bottom line is that onions are great for health when consumed in reasonable amounts. They provide a lot of benefits.

Onion Nutrition Facts

Below you can find information about the nutrients contained in 100 grams of onions such as white, red and yellow onions.

Nutrition Facts Serving Size: 100 grams Amount per serving Calories 42 % Daily Value* Total Fat 0.4 g 0.7% Saturated Fat 0.1 g 0.5% Trans Fat 0 g Polyunsaturated Fat 0.1 g Monounsaturated Fat 0.2 g Cholesterol 0 mg 0% Sodium 18 mg 1% Total Carbohydrate 8.3 g 3% Dietary Fiber 2.8 g 11% Insoluble Fiber 1.2 g Soluble Fiber 0.6 g Protein 1.1 g 2% Vitamin A 2IU 0% Vitamin C 6.5 mg 8% Calcium 7 mg 0% Iron 0.4 mg 2%

*Percent Daily Values are based on a 2000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

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1. Wikipedia

2. AOCS Official Methods

3. USDA National Nutrient Database

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