Quercetin
Quercetin is a widely consumed flavonoid found in onions, apples, berries, and tea. Despite significant hype, human evidence is mostly D-grade - it has NOT lived up to its preclinical promise. Low bioavailability is a major limitation (~2%). May reduce CRP inflammation in younger adults (<45). Popular during COVID-19 due to in vitro studies but NO proven clinical benefit. Used as zinc ionophore in some protocols. Better absorbed as isoquercetin or with bromelain/fat. Most clinical trials show no effect.
Quick Answer
What it is
Quercetin is a widely consumed flavonoid found in onions, apples, berries, and tea. Despite significant hype, human evidence is mostly D-grade - it has NOT lived up to its preclinical promise.
Key findings
- Grade C: Anxiety Symptoms (Type 2 Diabetes)
- Grade C: High-density lipoprotein (HDL) (High Cholesterol)
- Grade D: Blood Pressure (High Blood Pressure)
Safety
No specific caution or interaction language was detected in the current summary/outcome notes.
ℹ️ Quick Facts: Quercetin
Quick Facts: Quercetin
- Best Evidence:Grade C
- Conditions Studied:11
- Research Outcomes:52
- Key Effect:Sarcoidosis
Detailed Outcomes
Evidence by Condition
Best grade per condition (each condition may have multiple outcomes)
Research Citations (19)
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