What is Quercetin?
Quercetin is a flavonoid found abundantly in apples, onions, berries, tea, and many other fruits and vegetables. It's one of the most studied plant compounds for its antioxidant, anti-inflammatory, and senolytic properties.
As a senolytic, quercetin helps eliminate senescent "zombie" cells - damaged cells that accumulate with age and release inflammatory compounds (SASP) that accelerate aging and disease.
Research has shown that quercetin, especially when combined with dasatinib or fisetin, can effectively clear senescent cells from tissues, leading to improved physical function and reduced age-related decline.
How Quercetin Works
Quercetin exerts its anti-aging effects through multiple complementary mechanisms. Its senolytic action targets the survival pathways that keep damaged cells alive, specifically inhibiting HSP90, a protein that senescent cells depend on.
Beyond its senolytic properties, quercetin is a potent antioxidant that scavenges free radicals and reduces oxidative stress. It also inhibits inflammatory enzymes and cytokines, helping to reduce chronic inflammation.
Quercetin's Key Actions
- Inhibits HSP90 to eliminate senescent cells
- Powerful antioxidant that neutralizes free radicals
- Reduces inflammatory cytokines (IL-6, TNF-alpha)
- Supports immune function and allergy relief
- Enhances mitochondrial biogenesis
Senolytic Research
The landmark 2015 study by Zhu et al. published in Aging Cell demonstrated that the combination of quercetin and dasatinib (D+Q) effectively cleared senescent cells in mice, leading to improved physical function and extended healthspan.
Research in Nature Communications (2019) confirmed that senolytic treatment with D+Q reduced senescent cell burden in humans and improved markers of physical function in patients with idiopathic pulmonary fibrosis.
While quercetin alone is less potent than the D+Q combination, it still provides meaningful senolytic activity, especially when combined with fisetin or taken at higher intermittent doses.
Dosage Guidelines
Quercetin can be taken daily as an antioxidant and anti-inflammatory, or intermittently at higher doses for senolytic purposes. Bioavailability is naturally low, so look for enhanced formulations with bromelain or phytosome technology.
Dosing Protocols
- Daily Antioxidant: 500-1000mg per day with meals
- Senolytic Protocol: 1000-1500mg daily for 2-3 consecutive days, monthly
- Combined with Fisetin: 1000mg quercetin + 500mg fisetin for enhanced effect
- Best taken: With fat-containing foods; bromelain enhances absorption
Additional Health Benefits
Beyond its senolytic activity, quercetin offers a wide range of health benefits that make it a valuable supplement for overall wellness:
- Cardiovascular Support: Reduces blood pressure and improves endothelial function
- Immune Function: Supports healthy immune response and may reduce allergy symptoms
- Metabolic Health: Improves insulin sensitivity and supports healthy blood sugar levels
- Brain Health: Neuroprotective properties may support cognitive function
- Exercise Performance: May enhance endurance and reduce exercise-induced inflammation
Safety and Considerations
Quercetin has an excellent safety profile and has been consumed in foods for thousands of years. Most people tolerate supplemental doses well, with minimal side effects.
Potential interactions include blood thinners (quercetin may enhance anticoagulant effects), certain antibiotics, and cyclosporine. Consult a healthcare provider if you take prescription medications.
Some people experience mild GI discomfort at higher doses. Taking with food typically resolves this issue. Pregnant and nursing women should consult their healthcare provider before supplementing.