Quercetin

One of the most abundant dietary flavonoids, with antioxidant and anti-inflammatory activity. Its main limitation is poor bioavailability — plain quercetin aglycone is absorbed at under ~1%, so enhanced forms (phytosome, with bromelain, or taken with fat) are used to improve uptake.¹

Blood pressure: supplementation in hypertensive patients over 28 days significantly reduced blood pressure; ~500 mg of the aglycone form is the dose reported effective for BP and inflammation.²

Antioxidant/anti-inflammatory: most likely to show measurable benefit in people with elevated baseline inflammation.¹

Most clinical trials use 500–1,000 mg daily, often split into two doses. Doses up to 2,000 mg/day have shown mild-to-no side effects in research settings. Taking with fat, vitamin C, or bromelain improves absorption.²³

Oral, as capsules or tablets, often formulated with bromelain or vitamin C.

Store at room temperature, away from heat, light, and moisture.

Space apart from high-dose calcium/magnesium (they compete for absorption). Generally well tolerated; long-term high-dose safety is less established.