Quercetin is a plant pigment known as a flavonoid that is found in many foods and plants, such as red wine, onions, green tea, apples, and berries¹². Flavonoids, including quercetin, are recognized for their antioxidant and anti-inflammatory properties³.

Benefits and Uses

Quercetin has been studied for various potential health benefits, including:

1. Antioxidant Effects: It helps protect cells from oxidative stress and damage caused by free radicals³.
2. Anti-inflammatory Properties: Quercetin can modulate inflammation by affecting certain enzymes and pathways in the body³.
3. Immune Support: There is evidence suggesting that quercetin may boost immune function and reduce the severity and duration of illnesses such as upper respiratory tract infections⁴.
4. Cardiovascular Health: It may help in reducing the risk of cardiovascular diseases by improving metabolic function and reducing oxidative stress and inflammation².
5. Anticancer Potential: Some studies have indicated that quercetin may have anti-carcinogenic effects, potentially helping to prevent various types of cancer³.

Sources of Quercetin

Quercetin is abundant in a variety of foods:

• Fruits: Apples, cherries, berries (blueberries, cranberries)
• Vegetables: Onions, broccoli, asparagus
• Beverages: Green tea, red wine
• Others: Nuts, seeds, buckwheat¹³

Safety and Dosage

Quercetin is generally considered safe when consumed in typical dietary amounts. Supplements have been used safely in doses up to 1 gram daily for up to 12 weeks¹⁵. Potential side effects include abdominal discomfort, nausea, and headache, but these are rare and usually at rates similar to those seen with placebo¹.

Footnotes

1. MedlinePlus Supplements - Quercetin ↩ ↩² ↩³ ↩⁴

2. Health Benefits of Quercetin in Age-Related Diseases - PubMed ↩ ↩²

3. Overviews of Biological Importance of Quercetin: A Bioactive Flavonoid ↩ ↩² ↩³ ↩⁴ ↩⁵

4. Quercetin supplementation and upper respiratory tract infection ↩

5. Quercetin, Inflammation and Immunity ↩