Onions as Fat Free Nutrition - white onion

Onions as Fat Free Nutrition

You may think of onions as those white slices that come on your hamburger, but there’s more to onions than you think. Onions are part of the Allium family, which includes a whole range of flavorful root vegetables: garlic; red, white and yellow onions; scallions (also called green or spring onions); shallots, leeks and chives. All alliums grow as underground bulbs with above-ground leaves and a flower stalk.

Onions contain beneficial polyphenols, sulfur compounds and vitamin C. The sulfur compounds produce their distinctive sharp odor and strong flavor, while also providing some health benefits because of their anti clotting, antioxidant and anti-inflammatory properties. (Note that much of the research on the health benefits of alliums has focused on garlic, while onions are less thoroughly tested.)

These sulfur compounds are also responsible for making you “cry” when you slice an onion; when these compounds waft upward and mix with your natural tears, they form a mild (and irritating) sulfuric acid.

Nutrition by Variety
When you peel an onion, be sure to remove only the papery skin and any outer layer that’s damaged—don’t over peel!

All varieties of onions contain zero fat and cholesterol, and most have less than one gram of sodium, while they provide plenty of vitamins.

Onions as Fat Free Nutrition images - onions

Onions as Fat Free Nutrition images – onions

Red, white and yellow “cooking” or “storage” onions are widely available year-round; their papery skins help extend their shelf life. Red onions are typically stronger and more pungent. These onions are high in vitamin C.

 

Onions as Fat Free Nutrition - white onion

Onions as Fat Free Nutrition – white onion

Sweet onion varieties include Vidalia, Walla Walla and candy; these are mild and sweet-tasting, and are excellent in most recipes. They are also a good source of vitamin C and contain a small amount of calcium.

Onions as Fat Free Nutrition images - leeks

Onions as Fat Free Nutrition images – leeks

Leeks grow in upright cylinders instead of round bulbs; they’re typically buried deep in sandy soil to produce a longer white portion. Leeks are commonly sautéed as a flavor base in soups and sauces. They pack quite a vitamin punch with high levels of vitamin C and A, plus calcium and iron.

Onions as Fat Free Nutrition images - shallots

Onions as Fat Free Nutrition images – shallots

Shallots are small, reddish-brown bulbs that are commonly minced and sautéed as a flavor base or used raw in salad dressings. While their names are easily mistaken, shallots and scallions (detailed below) are not the same. They contain vitamins A and C and iron.

Onions as Fat Free Nutrition images - green onion

Onions as Fat Free Nutrition images – green onion

Green onions (also called scallions or spring onions) are slender, with an inch or two of white topped by long green leaves. The white and pale green portions are used in cooking, the green tops can be sliced thin as a garnish. They are a source of vitamins A and C, as well as calcium and iron.

Onions as Fat Free Nutrition images - chives

Onions as Fat Free Nutrition images – chives

Green onions (also called scallions or spring onions) are slender, with an inch or two of white topped by long green leaves. The white and pale green portions are used in cooking, the green tops can be sliced thin as a garnish. They are a source of vitamins A and C, as well as calcium and iron.

Buying and Storing
For sweet onions, cooking onions and shallots, look for bulbs that are undamaged, with no soft spots and their papery skins intact. For leeks and green onions, seek produce that’s clean, with leaves that are deep green and not withered or wilted. 

Leeks and green onions should be refrigerated for up to two weeks.

Alliums are also available in processed form, as in freeze-dried chives or onion granules or powder.

Cooking
Calorie-for-calorie, onions pack a huge flavor wallop, whether you eat them raw or cooked. 

If raw onion disagrees with you (or other people in the room with you!), don’t worry: Cooking onions doesn’t damage their nutritional benefits as long as you don’t cook them for more than seven minutes.

As a convenience, you can prepare chopped onions in advance and freeze them in small containers for later cooking; however, their flavor may lessen a bit. With raw alliums used in dressings or salsas, you can tame the strong taste by rinsing chopped onions (or scallions or shallots) under cold water in a strainer for a minute or two. Onions can be grilled, or cooked over low heat for a long time to caramelize them.