Celebrate the Onion

By Bonnie Brost, licensed and registered dietitian at Essentia Health.

The onion is a hardy vegetable that can be planted right now. It does well in cool climates and can be planted five to six weeks before the final spring frost date, which is early June here in the Northland. You can plant seeds or small starter bulbs.

Onions are the third largest fresh vegetable industry in the United States, according to the National Onion Association. Per person consumption is about 20 pounds per year, which translates to more than 450 semi-truck loads of onions used each day. 

There are two main kinds of onions, fresh and dry. Fresh onions include green onions, also known as scallions, and sweet onions, such as Vidalia, that are available in spring. Dry onions, also known as storage onions, can be yellow, white or red. Dry onions usually have a stronger, more pungent flavor. 

The onion' strong flavor and odor come from sulfuric compounds. These compounds cause our eyes to tear. To keep tearing to a minimum, refrigerate an onion for 30 minutes before cutting and leave the root end on as long as possible, which reduces the release of the sulfuric compounds. 

Onions provide a little vitamin C, folate, calcium and potassium. Onions are high in flavonoids, the antioxidants that can neutralize harmful free radicals and suppress inflammation in our bodies. One flavonoid is quercetin, which has been linked to protection from lung cancer and asthma.

For some people, onions can increase the symptoms of gastric esophageal reflux disease (GERD) and irritable bowel syndrome. Onions, especially when eaten raw, can bring on symptoms of GERD or heartburn because the valve between the esophagus and stomach does not to close well, allowing the acid from the stomach to come up into the esophagus. Some people can tolerate cooked onions or onion powder better than raw onions. 

For those with irritable bowel syndrome, onions are a source of fructans that need to be broken apart by an enzyme in the small intestine. If they don't have enough of this enzyme, the fructans continue into the large intestine where they ferment and result in gas, bloating and/or diarrhea. Avoiding all types of onion is best. Try adding onion flavor by sautéing large pieces of onion in oil, removing them and then only using the flavored oil.  This doesn't work with soup because fructans are soluble in water and remain in the soup. 

Here are two recipes featuring onions.

Marinated onions are a great addition to sandwiches and salads. Try different onions, such Vadalia onions for something sweeter or red onions to add some color. 

Marinated Onions

1 medium onion
1/4 cup extra virgin olive oil
1/4 cup rice vinegar or red wine vinegar
2 tablespoons honey or granulated sugar
1/4 teaspoon pepper
1/4 teaspoon garlic powder
1/4 teaspoon dried oregano

Peel and thinly slice onion. Separate into rings. Combine remaining ingredients in a jar with a tight-fitting lid. Shake until well blended. Add onions. Shake to coat onions. Refrigerate at least 8 hours. 

Nutrition facts
Serving:  About 6
Calories:  40
Total fat: 2 grams
Saturated fat: 0 grams
Trans fat: 0 grams
Cholesterol:  0 milligrams
Sodium: 1 milligram
Potassium: 35 milligrams
Carbohydrate:  6 grams
Fiber: 1 gram
Protein: 0 grams

French onion soup is usually very high in saturated fat and sodium but this one is more heart-healthy.
The traditional soup uses toasted French bread but whole-grain bread makes it more nutritious.

French Onion Soup
1 tablespoon olive oil 
4 cups thinly sliced sweet Vidalia onions
4 cups thinly sliced red onions
1/2 teaspoon sugar
1/2 teaspoon ground pepper
1/4 cup dry white wine
11/2 teaspoon Worcestershire sauce
6 cups unsalted beef stock (140 milligrams sodium or less per cup)
1/2 teaspoon chopped fresh thyme or 1/4 teaspoon dried thyme
3 slices whole-grain bread, toasted and cubed
¾ cup shredded Swiss cheese 

Heat olive oil in a stock pot over medium-high heat. Add onions and saute for 5 minutes. Stir in sugar, pepper and salt. Reduce heat to medium and cook 20 minutes, stirring frequently. Stir in wine, broth and thyme, bring to a boil.  Cover, reduce heat and simmer for 2 hours.

Preheat broiler. Place 8 ovenproof bowls on a pan. Add 1 cup of soup to each bowl. Add 1/2 slice of toast cut into cubes and then top with 2 tablespoons of Swiss cheese. Broil for 3 minutes until cheese begins to brown.

Nutrition facts
Servings: 6
Serving size: 1 cup
Calories: 195
Total fat: 7 grams
Saturated fat: 3 grams
Trans fat: 0 grams
Cholesterol: 13 milligrams
Sodium: 250 milligrams
Potassium: 150 milligrams
Carbohydrates: 21 grams
Fiber: 3 grams
Protein: 10 grams