Quercetin

Research shows that anti-inflammatory foods containing quercetin can help with a number of health problems, including heart disease, blood vessel problems, allergies, infections, chronic fatigue and symptoms related to autoimmune disorders like arthritis. It is a plant flavonol (from the flavonoid group of polyphenols). It is found in many fruits, vegetables, leaves, seeds, and grains. Quercetin inhibits a liver enzyme called UGT2B17 which breaks down hormones.

• Capers contain huge amounts of quercetin which is a powerful anti-inflammatory phytochemical compound.
• Olives are rich in quercetin. The health  benefits of olives mainly come from the excellent micro-nutrient content: iron, calcium, fiber, copper, vitamin E, vitamin K, choline, sodium, phenolic compounds and omega-9. Olives are a rich source of antioxidants such as oleuropein, hydroxytyrosol, tyrosol and oleonalic acid.
• Japanese green tea is rich in quercetin.
• Onions are rich in quercetin.
• Other foods to note are: Dock plant, red leaf lettuce, watercress, cilantro, asparagus, okra, romaine lettuce, green peppers, kale, cranberry, apples, radish, red wine and cherries.

Covid 19

Chloroquine is in the news right now as a magic bullet in the treatment of Covid-19. It was first synthesised in 1934 at Bayer, and it became a major antimalarial drug after World War II. One danger of chloroquine is liver toxicity, but studies have shown that quercetin  + chloroquine has a reduced liver threat.

Quercetin also had antiviral activity against HIV-luc/SARS, influenza A and Ebola. So it is thought that quercetin would be preventative to some degree against Covid-19.