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Onion extract

Best studied for: Allergy and hay fever relief; Blood pressure support; Scar and wound healing. Supports heart health, reduces allergy symptoms.

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What is onion extract? Onion extract is a natural substance derived from onions, which are commonly used in cooking. It contains a high concentration of antioxidants, flavonoids, and sulfur compounds, which are responsible for its medicinal properties. How does onion extract work for medicinal purposes? Onion extract works by reducing inflammation, improving blood flow, and promoting wound healing. It also has antibacterial and antifungal properties, which make it effective in preventing and treating infections. What are the active ingredients that are important for its medicinal properties? The active ingredients in onion extract include quercetin, kaempferol, sulfur compounds, and flavonoids. What forms does onion extract come in? Onion extract is available in various forms, including capsules, tablets, powders, and extracts. What if I have an imbalance or deficiency? There is no known deficiency of onion extract, but an imbalance in its consumption may affect its medicinal properties. When was onion extract first used for medicinal purposes? Onion extract has been used for medicinal purposes for thousands of years, dating back to ancient civilizations such as the Egyptians, Persians, and the Greeks.

Helps

What does Onion extract help with? Onion extract comes from the common kitchen onion. You can buy it as a capsule, a liquid, or a skin gel. Cooks and healers in many cultures have used onion for coughs, wounds, and swelling. High blood pressure Good evidence — human supplement trials on file; sizes and doses not recorded. In human studies, people who took onion extract had lower blood pressure. Both the top and bottom numbers fell. The drops were biggest in people whose pressure was already high. Our file does not record the trial sizes or doses. Evidence grade B · Traditional tier T3 High blood sugar and pre-diabetes Good evidence — human studies in people with type 2 diabetes; sizes and doses not recorded. Studies in people with type 2 diabetes found lower fasting blood sugar with regular use. Our file does not list the trial sizes or doses. In lab work, quercetin from onion improved how cells answer insulin. Other onion compounds slowed the enzymes that break starch into sugar. Evidence grade B · Traditional tier T3 Scars and healing skin Good evidence — several human studies of the topical gel; sizes and doses not recorded. Onion gel is one of the most studied plant products for scars. In human studies, raised or dark scars grew softer over weeks to months. Our file does not record the trial sizes or doses. Evidence grade B · Traditional tier T3 High cholesterol Early evidence — small human studies with modest results; sizes not recorded. Human studies found a small drop in LDL cholesterol. Onion flavonoids also shielded LDL from the damage that adds to artery buildup. The effect was modest. Our file lists no trial sizes or doses. Evidence grade C · Traditional tier T3 Bone loss after menopause Early evidence — early human research in older women; findings still preliminary. Early human research in older women linked eating onions with better bone density. One idea is that onion slows the breakdown of bone tissue. This work is early. Our file records no trial sizes or doses. Evidence grade C · Traditional tier T3 Allergies and hay fever Long traditional use · not yet tested in trials — lab work on quercetin plus user reports; no human trial on file. In lab studies, quercetin helped steady the cells that release histamine. Histamine drives sneezing, a runny nose, and itchy eyes. Many users say they get fewer flare-ups after several weeks of daily use. No human trial for allergies is on file. Evidence grade insufficient · Traditional tier T3 Joint pain and long-term inflammation Long traditional use · not yet tested in trials — lab pathway work only; no human trial on file. In lab studies, quercetin blocked several pathways the body uses to make inflammation. Some people take onion extract next to their usual anti-inflammatory drugs. No human trial of onion extract for joint pain is on file. Evidence grade insufficient · Traditional tier T3 Gut health and digestion Long traditional use · not yet tested in trials — general nutrition science on FOS fiber; no human trial of onion extract on file. Onions are among the richest sources of a fiber called FOS. FOS is well known to feed gut bacteria such as Lactobacillus and Bifidobacterium. That is general nutrition science, not a trial of this remedy. No human trial of onion extract for digestion is on file. Evidence grade insufficient · Traditional tier T3 Chest congestion and asthma Long traditional use · not yet tested in trials — tradition plus early lab work; no human trial on file. Many cultures have used onion for coughs and a stuffy chest. Early lab work looks at whether quercetin affects airway tissue. No human trial of onion extract for asthma or congestion is on file. Evidence grade insufficient · Traditional tier T3 What Onion extract has not been shown to do It has not been shown to replace allergy drugs, blood pressure drugs, or diabetes drugs. It has not been shown to erase scars; human studies showed softer texture, not removal. It has not been shown to lower blood

Onion extract

Quick Facts

  • What it is: A concentrated extract from common onions, packed with quercetin and sulfur compounds that have been used medicinally for thousands of years.
  • Main uses: Supports heart health, reduces allergy symptoms, helps control blood sugar, and calms inflammation throughout the body.
  • Best for: Allergy and hay fever relief, Blood pressure support, Scar and wound healing
  • Active ingredients: Quercetin, Kaempferol, Organosulfur compounds (alliin, dipropyl disulfide), Fructooligosaccharides (FOS), Anthocyanins (red onion varieties), Flavonoids
  • Forms: Capsule, Standardized extract (powder), Topical gel, Liquid extract (tincture), Whole food (raw or cooked)
  • Time to effect: 2–6 weeks for most systemic benefits; topical effects on scars may take 8–12 weeks.
  • Side effects: Generally very safe; may cause digestive discomfort, heartburn, or mild blood-thinning effects at higher doses.
  • Pregnancy & breastfeeding: Not assessed for this entry. Ask your doctor or midwife before use.

Educational information, not medical advice — ask your doctor or midwife.

What is onion extract?

Onion extract is a natural substance derived from onions, which are commonly used in cooking. It contains a high concentration of antioxidants, flavonoids, and sulfur compounds, which are responsible for its medicinal properties.

How does onion extract work for medicinal purposes?

Onion extract works by reducing inflammation, improving blood flow, and promoting wound healing. It also has antibacterial and antifungal properties, which make it effective in preventing and treating infections.

What are the active ingredients that are important for its medicinal properties?

The active ingredients in onion extract include quercetin, kaempferol, sulfur compounds, and flavonoids.

What forms does onion extract come in?

Onion extract is available in various forms, including capsules, tablets, powders, and extracts.

What if I have an imbalance or deficiency?

There is no known deficiency of onion extract, but an imbalance in its consumption may affect its medicinal properties.

When was onion extract first used for medicinal purposes?

Onion extract has been used for medicinal purposes for thousands of years, dating back to ancient civilizations such as the Egyptians, Persians, and the Greeks.

Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.

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