Quercetin
Also known as: Bioflavonoid, Flavonol, Plant Polyphenol, Antioxidant Flavonoid
Quercetin is a powerful bioflavonoid and antioxidant found in many plant foods, particularly apples, onions, tea, and berries. It has anti-inflammatory and antihistamine properties that make it valuable for immune function and allergy management. Quercetin crosses cell membranes effectively and can accumulate in tissues, providing sustained antioxidant protection.
Benefits
Powerful antioxidant reducing free radical damage and oxidative stress; natural antihistamine reducing allergy symptoms and inflammation; supports cardiovascular health and blood pressure regulation; promotes healthy immune function and response; has anti-inflammatory properties; supports brain health and may improve cognitive function; may reduce uric acid and support gout management.
Recommended Dosage
Typical supplementation ranges from 500-1000 mg daily, divided into two or three doses with meals. Quercetin absorption is enhanced when taken with vitamin C or taken with fatty meals. Some individuals use up to 1500 mg daily for allergy or inflammatory conditions. Consistent dosing for 2-4 weeks is needed for benefit.
Food Sources
Quercetin is abundantly found in apples (especially with skin), red onions, berries (blueberries, cranberries), leafy greens, tea, and citrus fruits. However, heat and processing reduce quercetin content; raw or lightly cooked vegetables provide the most quercetin per serving.
Side Effects
Well-tolerated in most individuals at normal supplemental doses. Mild side effects may include headache, tingling in limbs, or mild GI upset. Kidney irritation has been reported at very high doses (over 3000 mg daily). Most side effects are dose-dependent and reversible upon dose reduction.
Interactions
May enhance anticoagulant effects of blood thinners like warfarin; monitor INR levels if combining. May potentiate blood pressure medications, leading to excessive lowering; monitor BP. May enhance diabetes medication effects; monitor blood glucose. Safe to combine with other antioxidants and immune-supporting supplements.
Warnings
Not recommended during pregnancy without medical guidance. Individuals with kidney disease should use cautiously due to potential kidney irritation at high doses. Those with gout should consult healthcare providers, as quercetin metabolism may affect uric acid levels. May cause photosensitivity in some individuals.
Deficiency Symptoms
Quercetin deficiency is not a clinical condition, but inadequate dietary intake contributes to increased oxidative stress, chronic inflammation, and susceptibility to allergies and infections.
Frequently Asked Questions
What are the benefits of Quercetin?▼
Powerful antioxidant reducing free radical damage and oxidative stress; natural antihistamine reducing allergy symptoms and inflammation; supports cardiovascular health and blood pressure regulation; promotes healthy immune function and response; has anti-inflammatory properties; supports brain health and may improve cognitive function; may reduce uric acid and support gout management.
What is the recommended dosage for Quercetin?▼
Typical supplementation ranges from 500-1000 mg daily, divided into two or three doses with meals. Quercetin absorption is enhanced when taken with vitamin C or taken with fatty meals. Some individuals use up to 1500 mg daily for allergy or inflammatory conditions. Consistent dosing for 2-4 weeks is needed for benefit.
What foods contain Quercetin?▼
Quercetin is abundantly found in apples (especially with skin), red onions, berries (blueberries, cranberries), leafy greens, tea, and citrus fruits. However, heat and processing reduce quercetin content; raw or lightly cooked vegetables provide the most quercetin per serving.
What are the side effects of Quercetin?▼
Well-tolerated in most individuals at normal supplemental doses. Mild side effects may include headache, tingling in limbs, or mild GI upset. Kidney irritation has been reported at very high doses (over 3000 mg daily). Most side effects are dose-dependent and reversible upon dose reduction.
What are the symptoms of Quercetin deficiency?▼
Quercetin deficiency is not a clinical condition, but inadequate dietary intake contributes to increased oxidative stress, chronic inflammation, and susceptibility to allergies and infections.
Related Supplements
Vitamin D
Vitamins
Vitamin D is a fat-soluble vitamin that plays a crucial role in calcium absorption, bone health, immune function, and mood regulation. Unlike most vitamins, your body can produce vitamin D when your skin is exposed to sunlight, earning it the nickname 'the sunshine vitamin.'
Vitamin C
Vitamins
Vitamin C is a water-soluble vitamin and powerful antioxidant that the human body cannot produce on its own. It is essential for the growth, development, and repair of all body tissues and plays a role in many body functions including immune defense, collagen formation, and iron absorption.
Omega-3 Fish Oil
Fatty Acids
Omega-3 fatty acids are essential polyunsaturated fats that your body cannot make on its own. The two most important omega-3s found in fish oil are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). They play critical roles in brain function, heart health, and reducing inflammation throughout the body.
Supplement Disclaimer
This supplement information is for educational purposes only and should not replace professional medical advice. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a healthcare provider before starting any supplement, especially if you are pregnant, nursing, taking medications, or have a medical condition.