Daily quercetin supplementation dose-dependently increases plasma quercetin concentrations in healthy humans.

@article{Egert2008DailyQS,
  title={Daily quercetin supplementation dose-dependently increases plasma quercetin concentrations in healthy humans.},
  author={Sarah Egert and Siegfried Wolffram and Anja Bosy-Westphal and Christine Boesch-Saadatmandi and Anika E Wagner and Jan Frank and Gerald Rimbach and Manfred James Mueller},
  journal={The Journal of nutrition},
  year={2008},
  volume={138 9},
  pages={
          1615-21
        }
}
Our aim was to investigate the effects of an oral supplementation of quercetin at 3 different doses on plasma concentrations of quercetin, parameters of oxidant/antioxidant status, inflammation, and metabolism. To this end, 35 healthy volunteers were randomly assigned to take 50, 100, or 150 mg/d (group Q50-Q150) quercetin for 2 wk. Fasting blood samples were collected at the beginning and end of the supplementation period. Compared with baseline, quercetin supplementation significantly… 
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298 Citations
Highly Influential Citations
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Background Citations
130
Methods Citations
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Results Citations
24

298 Citations

Quercetin supplementation does not alter antioxidant status in humans
TLDR
Quercetin supplementation over 12 weeks in doses of 500 mg or 1000 mg/day significantly increased plasma quercet in levels, but had no influence on several measures of oxidative stress and antioxidant capacity.
Quercetin bioavailability is associated with inadequate plasma vitamin C status and greater plasma endotoxin in adults.
The variable plasma quercetin response to 12-week quercetin supplementation in humans
TLDR
In summary, quercetin supplementation in doses of 500 and 1000 mg/day caused large but highly variable increases in plasma quercETin that were unrelated to demographic or lifestyle factors.
Effects of daily quercetin-rich supplementation on cardiometabolic risks in male smokers
TLDR
Daily quercetin-rich supplementation from onion peel extract improved blood lipid profiles, glucose, and blood pressure, suggesting a beneficial role for quercETin as a preventive measure against cardiovascular risk.
Effects of quercetin on uric acid metabolism
TLDR
Quercetin supplementation can maintain blood uric acid level and blood pressure within a low-risk range and is probably a result of regulated purine metabolism by quercet in, its microbial derivatives and their metabolites.
Higher plasma quercetin levels following oral administration of an onion skin extract compared with pure quercetin dihydrate in humans
TLDR
Quercetin aglycone derived from onion skin extract powder is significantly more bioavailable than that from quercet in dihydrate powder filled hard capsules.
Influence of quercetin supplementation on disease risk factors in community‐dwelling adults
Dose–response to 3 months of quercetin-containing supplements on metabolite and quercetin conjugate profile in adults
TLDR
After accounting for age, sex and BMI, quercetin supplementation was associated with significant shifts in 163 metabolites/quercetIn conjugates (false discovery rate, P< 0·05); further research is required to understand the health implications of these shifts.
Chronic consumption of quercetin reduces erythrocytes oxidative damage: Evaluation at resting and after eccentric exercise in humans.
Quercetin reduces serum homocysteine level in rats fed a methionine-enriched diet.
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References

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TLDR
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TLDR
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TLDR
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TLDR
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