Yellow Onion (Allium cepa var. cepa)
Medicinal Profile of
Yellow Onion (Allium cepa var. cepa)
Yellow onions are one of the most widely cultivated onion varieties, prized not only for their culinary versatility but also for their medicinal potency. Compared to red onions, yellow onions are significantly richer in free quercetin, making them especially effective for allergy support where histamine reactivity, congestion, and inflammatory heat dominate. In terrain terms, yellow onion is most supportive for congestive boggy states (stuffy nose, sluggish mucus clearance), excitation and inflammatory patterns (allergic rhinitis, sinus irritation, vascular inflammation), and hypometabolic sluggishness (slow digestion and circulation).
-
👉 Tastes describe the initial impression a food or herb leaves on the tongue, and they reveal its deeper actions in the body, shaping digestion, circulation, and tissue response.
Pungent – Stimulates circulation, clears stagnation, and opens blocked passages.
Sweet (secondary) – Provides gentle nourishment that grounds the pungency and supports recovery.
Astringent (mild) – Tones tissues and helps reduce excessive secretions.
-
👉Qualities describe the felt nature of a substance or practice, and how it acts in the body beyond nutrients or chemistry.
Circulating – Increases movement of blood and fluids, helping clear congestion.
Drying – Reduces boggy dampness and mucus accumulation.
Light – Processes easily without burdening digestion.
Penetrating – Reaches deeply into tissues, stimulating clearance of stagnation.
-
Yellow onions are one of the richest dietary sources of quercetin in the free form, which is highly bioavailable and effective as a natural antihistamine. They also provide sulfur compounds (allyl sulfides, thiosulfinates), vitamin C, manganese, chromium, and fiber (fructooligosaccharides) that act as prebiotics to nourish beneficial gut flora.
-
Raw slices in salads or sandwiches — best for quercetin intake and circulation stimulation.
Cooked onions in soups or sautés — retain immune and cardiovascular benefits with gentler action.
Onion-honey syrup — traditional remedy for coughs, colds, and allergy congestion.
Poultices or compresses — applied topically for congestion or chest colds.
Extracts and supplements — concentrated quercetin forms often sourced from yellow onions.
Indicated Patterns by Affinity
👉 Indicated patterns describe the functional state of the body and its organs and/or tissues, showing whether they are dry, atrophied, too damp (pressure), stagnant, lax, inflammed, sluggish, tense or underactive. The Primary Indicated Pattern is the main state where this remedy works best. Secondary Indicated Pattern(s) are the patterns that often develop over time when the primary state is left unaddressed. The primary pattern must be supported first, as this allows the secondary patterns to naturally ease or resolve.
👉Affinities are the organ systems and tissues where the remedy acts most strongly.
-
Congestive / Boggy (Primary Indicated Pattern) – Thick mucus and sinus blockage slow clearance. Examples: stuffy nose, sinus congestion, phlegmy cough.
Yellow onions’ pungent and drying qualities break up mucus and open nasal passages.
Excitation / Irritative (Secondary Indicated Pattern) – Inflamed nasal tissues trigger sneezing and allergy irritation. Examples: hay fever, allergic rhinitis.
Quercetin stabilizes mast cells to reduce histamine-driven swelling and sneezing.
-
Excitation / Inflammatory (Primary Indicated Pattern) – Immune overactivity drives allergy and histamine responses. Examples: seasonal allergies, itchy eyes, hives.
Quercetin and rutin calm immune over-reactivity, while antioxidants reduce inflammatory cascades.
Hyporesponsive / Depressed (Secondary Indicated Pattern) – Frequent colds or sluggish immune defenses.
Sulfur compounds and vitamin C enhance immune response against pathogens.
-
Congestive / Sluggish (Primary Indicated Pattern) – Circulation slows and lipids accumulate. Examples: elevated cholesterol, vascular stagnation.
Sulfur compounds improve lipid metabolism, while quercetin protects vessels.
Excitation / Inflammatory (Secondary Indicated Pattern) – Oxidative stress irritates vascular tissue. Examples: fragile vessels, hypertension tendencies.
Flavonoids stabilize vessels and reduce oxidative injury.
-
Hypometabolic / Sluggish (Secondary Indicated Pattern) – Heavy digestion and low appetite.
Pungent stimulation awakens appetite and digestive fire, while FOS fibers feed gut flora.
-
👉 Medicinal actions describe the specific ways a food influences organ systems and body functions.
Immune & Inflammatory System
Immunomodulant (Primary) – Balances immune reactivity, reducing allergy overdrive while supporting defense.
Antiallergic (Primary) – Stabilizes mast cells and reduces histamine release to ease allergy symptoms.
Antimicrobial (Primary) – Sulfur compounds inhibit bacteria, viruses, fungi, and some parasites.
Anti-inflammatory (Primary) – Lowers excitatory heat and inflammatory cascades.
Antioxidant (Primary) – Protects immune and connective tissues from oxidative stress.
Antipyretic (Supportive) – Mildly helps reduce fever when used raw or in syrup.
Respiratory System
Anti-catarrhal – Clears swollen mucosa and thick catarrh.
Expectorant – Promotes expulsion of phlegm.
Decongestant – Opens nasal passages and reduces sinus swelling.
Bronchoprotective (Supportive) – Reduces irritation and reactivity in bronchi.
Antitussive (Supportive, folk) – Onion-honey syrup can calm coughs while mobilizing mucus.
Cardiovascular System
Cardioprotective (Primary) – Protects heart and vessels from oxidative and inflammatory damage.
Cholesterol Regulator (Primary) – Reduces LDL cholesterol and improves lipid metabolism.
Antithrombotic / Anti-platelet (Primary) – Decreases platelet aggregation and clot risk.
Vasoprotective (Primary) – Strengthens blood vessel walls and improves capillary integrity.
Antihypertensive (Supportive) – Promotes vascular relaxation and improved blood flow.
Hypolipidemic (Supportive) – Reduces blood lipids beyond cholesterol regulation.
Digestive System
Digestive Stimulant (Primary) – Awakens appetite and enhances digestive secretions.
Carminative (Primary) – Relieves gas and digestive tension.
Prebiotic (Primary) – Provides FOS to nourish beneficial gut flora.
Anti-ulcerogenic (Supportive) – Antioxidants may protect gut lining from irritation.
Vermifuge (Supportive, folk) – Traditionally used to expel intestinal parasites.
Urinary & Lymphatic Systems
Diuretic (Supportive) – Increases urinary output, helping clear fluids and metabolic waste.
Lymphagogue (Supportive) – Moves lymph to reduce congestion, especially with respiratory or skin conditions.
General / Systemic
Diaphoretic (mild) – Promotes gentle sweating, useful in colds.
Detoxifying (Traditional) – Historically regarded as a “blood purifier,” enhancing systemic clearance.
Adaptogenic (supportive) – Quercetin reduces systemic oxidative and inflammatory stress.
Skin / Topical Applications
Dermatologic Restorative (Supportive) – Onion extracts support scar healing and reduce fibroblast overgrowth.
Counter-irritant / Rubefacient (Supportive, folk) – Raw onion stimulates local circulation, useful in poultices for congestion or pain.
Antimicrobial (Primary, topical) – Inhibits bacteria and fungi when applied externally.
Wound Healing (Supportive) – Supports tissue repair through antimicrobial and antioxidant effects.
Hair Growth Stimulant (Supportive, folk) – Onion juice has been used topically to encourage scalp circulation and follicle health.
-
👉 Constituents are the natural compounds in a food that give rise to its actions in the body.
Quercetin (free form, highly bioavailable) – Natural antihistamine, antioxidant, and vascular protectant.
Rutin and other flavonoids – Stabilize capillaries and reduce oxidative stress.
Sulfur compounds (allyl sulfides, thiosulfinates, cepaenes) – Provide antimicrobial, cholesterol-lowering, and circulation-enhancing effects.
Vitamin C – Supports immunity and collagen repair.
Fructooligosaccharides (FOS) – Prebiotic fibers that improve gut health.
-
2nd Degree – Stronger than most foods due to concentrated quercetin and sulfur compounds, yet safe for regular use in both diet and folk remedies.
-
May potentiate anticoagulants (due to sulfur compounds reducing platelet stickiness).
May enhance effects of antihypertensives.
May modestly lower blood sugar, requiring caution with hypoglycemic medications.
-
Generally safe in dietary and moderate medicinal use.
Raw onions may aggravate reflux or stomach irritation in sensitive individuals.
Excess use may worsen dryness in very dry constitutions.
Safe in pregnancy and lactation in food amounts.
Safety Notes for Topical Use
Raw onion on skin can cause redness, stinging, or irritation, especially in sensitive individuals.
Prolonged or repeated contact may cause dermatitis.
Onion extract gels are generally safer than applying raw onion directly.
-
Traditional Sources
European folk medicine – onions layered with honey for coughs, syrups for colds.
Eclectic herbal texts – pungent expectorant and circulatory stimulant.
Ayurveda – heating, pungent digestive stimulant.
Modern Sources
Griffiths, G., Trueman, L., Crowther, T., Thomas, B., & Smith, B. (2002). Onions—A global benefit to health. Phytotherapy Research, 16(7), 603–615.
Slimestad, R., Fossen, T., & Vågen, I. M. (2007). Onions: A source of unique dietary flavonoids. Journal of Agricultural and Food Chemistry, 55(25), 10067–10080.
Lanzotti, V. (2006). The analysis of onion and garlic. Journal of Chromatography A, 1112(1–2), 3–22.
Andres, S., et al. (2018). Safety aspects of the use of quercetin as a dietary supplement. Molecular Nutrition & Food Research, 62(1).
National Institutes of Health (NIH) – Flavonoids and Quercetin fact sheets.
