Onion
Onions, scientifically known as Allium cepa, are a widely consumed vegetable belonging to the Allium genus, which also includes leeks, shallots, and garlic. They are primarily cultivated for their mature bulbs but can also be harvested at an immature stage, allowing both the bulbs and green tops to be enjoyed. Onions are categorized into storage onions, which have a long shelf life and come in varieties such as yellow, red, and white, and sweet onions, known for their high water content and shorter freshness duration, including types like Vidalia and green onions. The United States is a significant producer of onions, exporting large quantities to countries including Canada and Japan.
Historically, onions have been consumed since ancient times, with evidence of cultivation dating back over five thousand years in regions like China and the Middle East. They have been associated with various cultural beliefs and practices, from ancient Egyptian burial rites to their consumption by Roman soldiers. In modern times, onions are not only a staple in numerous dishes worldwide but are also recognized for their health benefits, containing nutrients such as vitamin C and quercetin, which may help reduce the risk of certain diseases. However, onions can also be polarizing due to their strong odor and irritants that can cause tears when chopped. Some individuals may experience allergies or exacerbated symptoms of medical conditions when consuming onions, particularly raw ones.
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Onion
The onion is a common vegetable that comes in many varieties. Onions (Allium cepa) are part of the genus Allium, which includes leeks, shallots, and garlic. Onion plants are often grown and harvested for their mature bulbs. However, immature onions can also be harvested, and their bulbs and green tops can be eaten. Onions are often categorized by storage life. Bulb onions are referred to as storage onions because they can be kept for several months without spoiling. Storage onions are then further divided by color—yellow, red, and white. Some of the most common storage onions include Bermuda, pearl, Spanish, and red onions. Spring or summer onions, which are sometimes referred to as sweet onions, have high water content and do not stay fresh for long. Common varieties of sweet onions include green onions, scallions, and Vidalia onions.
According to the National Onion Association, the United States produces about 6.75 billion pounds of onions each year, making it the world's sixth largest onion producer. By 2022, most of its onions were being exported to Canada, Mexico, Japan, the Bahamas, and Chinese Taipei.
Brief History
People around the world have been eating wild onions since ancient times. There is some debate about where the onion plant was first cultivated. Some experts believe that onions were domesticated in central Asia, but others think they were first farmed in Iran or Pakistan. Records suggest that the Chinese grew onions in their gardens more than five thousand years ago, and an Indian medical text from the sixth century BCE touts the health benefits of onions. The ancient Egyptians believed that onions, with their round shape and circle-like layers, were symbols of eternity. The Egyptians painted images of onions on the inner walls of pyramids and tombs, and some researchers suspect that they buried mummies with onions because they believed the strong smell would encourage the dead to breathe again.
Onions are mentioned in the Bible, and ancient Olympic athletes and gladiators ate onions before competitions and even rubbed them on their bodies, supposedly to help firm their muscles. In her book How Carrots Won the Trojan War: Curious (but True) Stories of Common Vegetables, author Rebecca Rupp notes that members of the Roman military regularly ate onions and other Alliums, as it was believed these vegetables helped promote strength and bravery. Rupp even claims that the Romans helped spread the vegetable across Europe.
By the Middle Ages, onions were a common food, but they were also used for many medicinal purposes. Onions were prescribed to treat everything from headaches to hair loss. The Pilgrims brought onions to the New World on the Mayflower; however, they soon found that wild onions were very common in North America. By the time Europeans arrived, Native Americans were already using wild onions for food, in poultices, and in dyes. Wild onions even allegedly saved French explorer and missionary Père Marquette and his team from dying of starvation on a journey from Green Bay, Wisconsin, to Chicago, Illinois, in 1674.
Early Americans grew onions in their gardens and enjoyed them in a variety of dishes. Onions were even the favorite vegetable of the nation's first president, George Washington. During the colonial era and beyond, people still used onions for medicinal purposes, such as treating insomnia, pneumonia, and diabetes. In the 1800s, people believed onion juice was an effective antibiotic, and it was used to treat wounded soldiers on the battlefields during the Civil War (1861–1865). In fact, General Ulysses S. Grant wrote a letter to the War Department notifying the government that he would not move his troops without onions. After that, he promptly received several shipments of the prized vegetable.
Overview
Today, onions are consumed around the world, and they are enjoyed in dishes served at breakfast, lunch, and dinner. Onions are important components in many condiments and sauces, including salsa and spaghetti sauce. The National Onion Association estimates that US onion consumption has increased by more than 70 percent since 1982. Worldwide onion consumption is estimated at 13.67 pounds per person annually.
While no longer used as medicine, onions are still valued for their health benefits. Onions contain important nutrients such as vitamin C, iron, and calcium. They are fat free and contain no cholesterol and little sodium.
Studies have shown that onions can help decrease blood pressure and reduce the risk of experiencing cardiac arrest. Onions also contain quercetin, an antioxidant, which helps reduce oxidative damage to body cells. Some research suggests that eating foods rich in quercetin could help prevent breast, colon, ovarian, lung, gastric, and bladder cancers. Some studies have also shown that onions can help aid in digestion, act as an anti-inflammatory, help control blood sugar levels, and increase bone density.
Despite these benefits, onions are one of the more polarizing vegetables. This might be because most onions produce an extremely strong smell. In fact, the sulfur found in onions is similar to the compound found in skunk spray, which is why American cowboys used to refer to onions as "skunk eggs." Onions also contain an irritant called syn-propanethial-S-oxide that is released when chopping the odorous vegetables. When syn-propanethial-S-oxide hits the eyes, the brain recognizes it as an irritant and sends signals to the body to release tears to flush out the chemical. There are many suggestions about how to reduce tears while chopping onions, including chilling the onions before chopping them or using a fan to help disperse the syn-propanethial-S-oxide before it reaches the eyes.
Although onions have many health benefits, a diet rich in these vegetables is not recommended for everyone. Some people have an onion allergy, which can cause itchy eyes, rashes, and vomiting. Additionally, people with other medical conditions may find that eating onions can exacerbate symptoms of their disease. Eating raw onions can worsen heartburn, especially in people who suffer from acid reflux disease. Some studies also show that eating large amounts of green onions could reduce the effectiveness of certain blood-thinning medications; therefore, patients taking these drugs need to be cautious about their onion intake.
Bibliography
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Cavazos, Amelia. "Onions." Colorado State University, 2020, fsi.colostate.edu/onions/. Accessed 19 Jan. 2023.
"Consumption." National Onion Association, www.onions-usa.org/all-about-onions/consumption. Accessed 19 Jan. 2023.
"History of Onions." National Onion Association, www.onions-usa.org/all-about-onions/history-of-onions. Accessed 11 Oct. 2016.
"How & Where Onions Are Grown." National Onion Association, www.onions-usa.org/all-about-onions/where-how-onions-are-grown. Accessed 11 Oct. 2016.
"Onion Health Research." National Onion Association, www.onions-usa.org/all-about-onions/onion-health-research. Accessed 11 Oct. 2016.
Rupp, Rebecca. How Carrots Won the Trojan War: Curious (but True) Stories of Common Vegetables. Storey Publishing, 2011, pp. 195–209.
Rupp, Rebecca. "The Vegetable That Treated Gunshot Wounds." National Geographic, 1 Dec. 2014, theplate.nationalgeographic.com/2014/12/01/stinky-smelly-wonderful-onions/. Accessed 11 Oct. 2016.
Stanton, Meredith. "Onions: Full of Nutrients." WebMD, www.webmd.com/diet/features/onions-full-of-nutrients. Accessed 11 Oct. 2016.
Szalay, Jessie. "Onions: Health Benefits, Health Risks & Nutrition Facts." Live Science, 16 Oct. 2014, www.livescience.com/45293-onion-nutrition.html. Accessed 11 Oct. 2016.
"Types of Onions." Berkeley Wellness, 12 Aug. 2012, www.berkeleywellness.com/healthy-eating/food/article/types-onions. Accessed 11 Oct. 2016.