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Allium vegetables are the most versatile of all making your soups, stew, and curries aromatic, flavorful, and delectable for ages. Allium is the collective term used for the family that contains Onions, garlic, shallot, spring onion, leek, and chives. It is the most used vegetable all around the world. Being enriched with multiple antioxidants, Sulfur compounds, and phenolic compounds, (1) Allium is a must-have
vegetable among health enthusiasts. Few of us cannot stand its lingering smell after we eat it. This pungent smell is due to the sulfur content present in it. Several research mentions that a more robust flavor of onion provides better protection against certain cancers. Onions, garlic, and other allium herbs are well-researched plant products for therapeutic use. A variety of health-promoting effects are therefore well documented in its bioactive compounds, including antioxidants, antimicrobials, anti-inflammatory agents, anti-obesity, anti-diabetics, anti-cancer agents, cardiovascular protection, neuroprotection, liver and kidney protection, respiratory system protection, and digestive system protection.
The Benefits of Eating Alliums
Onion:
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Onions contain organosulfur compounds and antioxidant flavonoids, quercetin, and anthocyanin. Quercetin's antioxidant properties may reduce inflammation (5), kill cancer cells,(7) control blood sugar(8), and prevent heart disease. Anthocyanin imparts red/purple color to certain varieties. Anthocyanin can heal and provide a wide range of health benefits. Consuming onions may reduce the risk of atherosclerosis, a dangerous plaque buildup inside arteries. Additionally, onions have been shown to fight inflammation, an essential factor in cardiovascular disease, heart attacks, and strokes. Onions have a longer shelf life; No wonder this humble veggie is part of almost all the cultures and cuisines of the world.
Garlic:
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Garlic is an excellent natural source of bioactive sulfur-containing compounds and has promising in preventing and managing specific diseases. Since ancient times Garlic has been used to cure skin disease, rheumatism, lack of appetite, weakness, common cold and cough, and many other ailments worldwide. (12)Garlic contains the unsaturated sulfur compound Allicin, which has an antibacterial property. Allicin and other garlic compounds can combat respiratory tract disease. In many studies on rats and rabbits, allicin and other sulfur compounds decrease lipid, cholesterol, and triglyceride. Garlic reduces blood pressure in hypertensive individuals. (11) Garlic contains compounds known as Ajoenes (25)and can prevent blood clots. Garlic is a powerful antioxidant. Garlic protects the heart and is very effective against arteriosclerosis. (13) It also lessens the risk of getting Alzheimer’s and dementia. Garlic potentially reduces the risk of several cancers (9).
Shallot:
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I loved pickled shallots as a kid, primarily served in restaurants in India. However, I never realized how healthy they could be. It has an onion-like flavor but is far milder than onion. This sweet-tasting allium is highly nutritious due to its many antioxidants, including allicin and quercetin. They're packed with fiber, vitamins, minerals, and organosulfur compounds that contribute to supporting good health. In addition, Ethyl acetate extracts (EEOs) found in shallots can help slow cancerous cell growth. There is also a high potassium content in shallots. Our body relies on potassium to maintain fluid levels, and it also plays an essential role in nerve and muscle function, including heart muscle. Quercetin in Shallot allows it to fight against allergies and inflammatory respiratory diseases.
Leek:
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The edible part of this plant is the stalk. Leek contains reasonable amounts of magnesium and vitamins A, C, and K, as well as copper, vitamin B6, iron, and folate. Leek is a source of fiber that keeps you full for a longer time. Leek is a prebiotic, which is associated with keeping your gut healthy. Leek contains a flavonoid called kaempferol (20), and several pharmaceutical activities are related to this compound, such as antioxidant, anti-inflammatory, antimicrobial, antidiabetic, and cancer-fighting properties (19). With their high sulfur content, leeks can lower cholesterol and blood pressure and prevent blood clots from forming.
Spring onions/Scallion:
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Scallion is essentially premature onions harvested before their bulb has formed. It tastes very mild compared to its other allium cousins. Scallions are a rich source of vitamins K, C, and E. Besides adding crunch and color to your salad, it supports eye health, strengthens your bones, and boosts immunity. It is rich in fiber that keeps you full for a longer time, supports heart health, and controls blood sugar. Being a member of the allium family, scallions are rich in organosulfur compounds and flavonoids that combat the enzymes responsible for cancer cell production.
Chives:
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Chives are the allium variety that grows in your yard like a weed. Primarily, it is used for garnishing food, and it has been found to contain some medicinal properties. Chives contain Choline and folate; individually, both are good for your memory function. This herb is rich in vitamin K, which is vital for bone health. The consumption of chives and other alliums may prevent the development of cancer.
Caution:
Although onions and garlic are not common allergens, they might trigger allergic reactions in a few individuals. (24)
Onion and garlic fall in the high FODMAP food category. It can cause pain and discomfort to individuals with IBS (irritable bowel syndrome) or SIBO (small intestinal bacterial overgrowth). However, the green parts of scallions, leeks, and chives are low FODMAP and can be enjoyed in small quantities. (27)
References:
Cholesterol-Lowering Effect of Allicin on Hypercholesterolemic ICR Mice - PMC (nih.gov)
Effect of garlic on blood pressure: a systematic review and meta-analysis - PubMed (nih.gov)
Garlic (Allium sativum L.) and cardiovascular diseases - PubMed (nih.gov)
Anti-allergic effects of herbal product from Allium cepa (bulb) - PubMed (nih.gov)
Quercetin and Its Anti-Allergic Immune Response - PMC (nih.gov)
Cardiovascular Health Benefits of Specific Vegetable Types: A Narrative Review - PMC (nih.gov)
A review on the dietary flavonoid kaempferol - PubMed (nih.gov)
Garlic (Allium sativum L.) Bioactives and Its Role in Alleviating Oral Pathologies - PMC (nih.gov)
Anaphylactic reaction to the ingestion of raw onion. A case report - PubMed (nih.gov)
Low-FODMAP Diet for Treatment of Irritable Bowel Syndrome - PMC (nih.gov)
Loved your pictures of vegetables and new article ! Very informative!! Keep up the good work Shruti!!