The beneficial effects of flavonoids, like quercetin, come from their antioxidant content. It can often be found in natural anti-histamine supplements. Whilst there is little evidence at the moment to prove any health benefits fully, one UK study has found that quercetin has anti-bacterial properties.

Quercetin content is highest in onions but it can be found in abundance in apples, honey, raspberries, red grapes, cherries, citrus fruits, and green leafy vegetables

Studies have shown liposomal quercetin can significantly improve the solubility and bioavailability of quercetin.