QU995
Also known as: Quercetin, QU995, C15H10O7
Overview
Quercetin is a naturally occurring flavonoid polyphenol found in various fruits, vegetables, and grains, such as onions, apples, and berries. QU995 is a branded, highly purified form of quercetin. It is primarily utilized as a dietary supplement for its potent antioxidant, anti-inflammatory, and immune-modulating properties. Research indicates its potential benefits in areas such as muscle recovery after intense exercise, improvement of glycemic control, and reduction of oxidative stress. The evidence base for quercetin is moderately mature, with numerous randomized controlled trials (RCTs) and meta-analyses supporting some of its reported effects, particularly concerning exercise recovery and metabolic health. It is characterized by its strong capacity to scavenge reactive oxygen species and modulate inflammatory pathways.
Benefits
Quercetin offers several evidence-based benefits. For muscle recovery, supplementation with approximately 1000 mg/day has been shown to significantly reduce muscle soreness (SMD: -1.33; p=0.03) and creatine kinase levels (SMD: -1.15; p=0.02) following intense exercise, thereby accelerating the recovery of muscle function, particularly in sedentary to well-trained young men. Regarding glycemic control, doses of 500 mg/day or more for at least 8 weeks have significantly reduced fasting plasma glucose (WMD: -0.94 to -1.08 mmol/L) and insulin concentrations in individuals with metabolic syndrome or related disorders. Beyond these primary effects, quercetin also exhibits strong antioxidant and anti-inflammatory properties, demonstrated by reduced oxidative stress post-exercise (SMD: -0.92; p=0.03). While in vitro and animal studies extensively support its anti-inflammatory and antioxidant roles, human data specifically confirm its ability to mitigate oxidative stress. The effect sizes for muscle recovery are moderate to large, while glycemic improvements are modest but statistically significant. Benefits for glycemic control typically require at least 8 weeks of supplementation, whereas muscle recovery effects can be observed within 7 days to 12 weeks.
How it works
Quercetin exerts its effects primarily through its potent antioxidant and anti-inflammatory properties. As an antioxidant, it directly scavenges reactive oxygen species, thereby reducing oxidative stress and cellular damage. Its anti-inflammatory actions involve the modulation of various inflammatory mediators and signaling pathways, helping to mitigate inflammation in the body. Quercetin also influences metabolic pathways, particularly those involved in glucose regulation and insulin signaling, which contributes to its observed benefits in glycemic control. It interacts with the musculoskeletal system by reducing exercise-induced muscle damage and inflammation, facilitating faster recovery. At a molecular level, it targets inflammatory enzymes and oxidative stress markers, and may influence enzymes related to glucose metabolism. Quercetin has moderate bioavailability, and specialized formulations like QU995 aim to enhance its absorption and efficacy.
Side effects
Quercetin is generally considered safe when taken at recommended dosages of up to 1000 mg/day for durations up to 12 weeks, with no serious adverse effects reported in clinical trials. The most commonly reported side effect is mild gastrointestinal discomfort, which is infrequent. However, caution is advised regarding potential drug interactions. Quercetin may interact with anticoagulants (blood thinners) and certain antibiotics due to its influence on cytochrome P450 enzymes, which are involved in drug metabolism. Individuals on these medications should consult a healthcare provider before supplementing with quercetin. There is limited safety data for pregnant and lactating women, so its use is generally not recommended in these populations. Furthermore, the safety and efficacy of quercetin in special populations such as the elderly, children, or individuals with severe chronic diseases are not well established, warranting caution and medical consultation.
Dosage
For muscle recovery and antioxidant effects, an optimal dosage of around 1000 mg/day is recommended. For benefits related to glycemic control, a minimum effective dose of 500 mg/day or more is suggested. Quercetin should be taken daily. For glycemic control, effects typically require at least 8 weeks of consistent supplementation, while muscle recovery benefits can be observed after 7 days to 12 weeks. The maximum safe dose identified in current RCTs is up to 1000 mg/day for durations up to 12 weeks; higher doses require further research to establish safety. QU995 is a highly purified form, which may offer improved consistency and purity. Absorption can be influenced by food intake, and formulations designed to enhance bioavailability are preferred. No specific cofactors are identified as required for its efficacy.
FAQs
Is QU995 the same as quercetin?
QU995 is a branded, highly purified form of quercetin. It contains the same active compound, quercetin, but may offer enhanced consistency and purity compared to generic forms.
Is it safe to take 1000 mg daily?
Yes, taking 1000 mg of quercetin daily has been shown to be safe for up to 12 weeks in healthy adults, based on current randomized controlled trial evidence.
How long before effects appear?
For glycemic control, benefits typically require at least 8 weeks of consistent use. Muscle recovery benefits can be observed within days to weeks of supplementation.
Does it interact with medications?
Yes, quercetin may interact with anticoagulants and certain antibiotics. It is crucial to consult your healthcare provider if you are taking any medications before starting quercetin supplementation.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/30848564/ – This systematic review and meta-analysis of 9 RCTs found that quercetin supplementation (≥500 mg/day for ≥8 weeks) significantly reduced fasting plasma glucose and insulin concentrations in individuals with metabolic syndrome. The study highlights quercetin's potential in improving glycemic control, despite moderate heterogeneity among included studies.
- https://pubmed.ncbi.nlm.nih.gov/37398956/ – This systematic review and meta-analysis of 13 RCTs involving 249 participants demonstrated that 1000 mg/day of quercetin significantly reduced muscle soreness, creatine kinase levels, and oxidative stress after exercise. The findings support quercetin's role in accelerating muscle recovery, though some risk of bias concerns were noted.
- https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1636970/full – This systematic review and network meta-analysis, encompassing multiple RCTs, confirms quercetin's heterogeneous but significant effects on muscular strength and recovery. The study provides high methodological rigor, reinforcing quercetin's efficacy in muscle-related outcomes despite variations in protocols and dosages across studies.
