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Pqq4.5
PQQ Research
Likely helps
28 peer-reviewed studies
What the evidence says
Likely helps
PQQ appears to help in 3 of 3 studies with measurable effects — the evidence leans clearly favourable.
Most evidence is from high-quality randomised trials published 2010–2026 with a typical study size of 34 participants.
Based on 28 studies · 10 RCTs · 453 total participants
Confidence
Moderate confidence
What the studies found
3helped· 25 more without graded effect data
By outcome
Cognitive functionSome memory benefit in small trials; evidence is limited · 4-8 weeks
Likely helps26 studies
Inflammation
Mostly mechanism / observational9 studies
Longevity & agingMitochondrial-biogenesis mechanism; no human longevity outcomes · Ongoing
Energy & fatigueNo improvement in exercise performance in the one trial testing it · 4-8 weeks
Mostly mechanism / observational4 studies
Therapeutic & clinical
Mostly mechanism / observational4 studies
Endurance & exercise performance
Too few graded studies1 study
Sleep & insomnia
Too few graded studies1 study
Cholesterol & lipids
Too few graded studies1 study
Bone health
Too few graded studies1 study
Glucose & metabolicMetabolic claims rest on mechanism and small studies, not outcomes · 8-12 weeks
Too few graded studies1 study
Fertility & reproductive
Too few graded studies1 study
Safety profile
Too few graded studies1 study
By the numbers
Pulled from 21 studies with measurable effects
Likely real effects
50%
across studies
People studied
453
typical study: 34 people
Strongest designs
10
0 pooled, 10 randomised
Showed benefit
100%
3/3 studies
How long studies ran
1–3 months
2
3+ months
2
Populations Studied
Not specified3
General population2
Healthy adults2
Patients with neurological disorders1
Active research area
16 studies in the last 5 years
201020182026
1Anti-aging effect comparison of PQQ and NMN/NRSystematic ReviewCited 2×2026
Despite supporting preliminary data and patented formulations, strong scientific evidence encouraging the synergistic anti-aging potential of PQQ and NMN/NR remains limited, highlighting the need f...
Ulpathakumbura S et al. · Ageing research reviews (2026)
Despite supporting preliminary data and patented formulations, strong scientific evidence encouraging the synergistic anti-aging potential of PQQ and NMN/NR remains limited, highlighting the need for robust studies.
Collectively, PQQ and NMN/NR offer distinct complementary strategies to promote healthy aging and prevent age-related diseases; their combination could offer a more effective approach to enhance healthy aging and longevity.
2Protective effects of PQQ in CNS disordersSystematic ReviewCited 1×2026
This review will address the biochemical properties, mechanism of action, and physiological roles of PQQ with a specific focus on its antioxidant and anti-inflammatory effects as well as its role i...
Aboulhassane S et al. · The Journal of nutritional biochemistry (2026)
This review will address the biochemical properties, mechanism of action, and physiological roles of PQQ with a specific focus on its antioxidant and anti-inflammatory effects as well as its role in enhancing mitochondrial function.
The therapeutic implications of these findings will be discussed, emphasizing PQQ's potential as a novel pharmacological approach for the management of neurological disorders, including its emerging role in cerebral folate deficiency.
4PQQ therapeutic role in neurodegenerative diseasesSystematic ReviewCited 6×2025
Xie T et al. · Molecular biology reports (2025)
By improving cellular energy metabolism, reducing oxidative stress, and promoting neuronal survival, PQQ offers a multifaceted approach to counteracting the pathophysiological factors underlying neurodegeneration.
Our review focusing on current study of PQQ on its enhancing neuroplasticity, and protecting neurons from damage induced by oxidative stress, mitochondrial dysfunction, and inflammation.
Further we reviewed the significant signaling pathways that involved PQQ neuroprotective mechanisms, positioning it as a novel candidate for future therapeutic strategies targeting these debilitating conditions.
Taken together, current observations suggest vitamin-like PQQ has strong potential as a potent therapeutic nutraceutical.
Jonscher KR et al. · Biomolecules (2021)
Here, we address PQQ's role as an enzymatic cofactor or accessory factor and highlight mechanisms underlying PQQ's actions.
We review both large scale and targeted datasets demonstrating that a neonatal or perinatal PQQ deficiency reduces mitochondria content and mitochondrial-related gene expression.
Data are reviewed that suggest PQQ's modulation of lactate acid and perhaps other dehydrogenases enhance NAD+-dependent sirtuin activity, along with the sirtuin targets, such as PGC-1α, NRF-1, NRF-2 and TFAM; thus, mediating mitochondrial functions.
8Chronic disease and premature aging riskSystematic ReviewCited 184×2018
Because nutrient deficiencies are highly prevalent in the United States (and elsewhere), appropriate supplementation and/or an improved diet could reduce much of the consequent risk of chronic disease and premature aging.
Ames BN · Proceedings of the National Academy of Sciences of the United States of America (2018)
Impairment of the function of longevity proteins results in an insidious acceleration of the risk of diseases associated with aging.
I also propose that nutrients required for the function of longevity proteins constitute a class of vitamins that are here named "longevity vitamins." I suggest that many such nutrients play a dual role for both survival and longevity.
Because nutrient deficiencies are highly prevalent in the United States (and elsewhere), appropriate supplementation and/or an improved diet could reduce much of the consequent risk of chronic disease and premature aging.
Wen H et al. · Current stem cell research & therapy (2020)
Owing to the inherent properties of PQQ as an antioxidant and redox modulator in various systems.
In recent years, the role of PQQ in the field of osteoporosis and neuro injury has become a research hotspot.
This article mainly discusses the derivatives, distribution of PQQ, in vitro models of osteoporosis and neuro injury, and the research progress of its mechanism of action.
10Health benefits of pyrroloquinoline quinoneSystematic ReviewCited 90×2016
Additionally, we provide an update of its basic pharmacokinetics and safety information in oral ingestion.
Akagawa M et al. · Bioscience, biotechnology, and biochemistry (2016)
Although PQQ is not currently classified as a vitamin, PQQ has been implicated as an important nutrient in mammals.
In recent years, PQQ has been receiving much attention owing to its physiological importance and pharmacological effects.
In this article, we review the potential health benefits of PQQ with a focus on its growth-promoting activity, anti-diabetic effect, anti-oxidative action, and neuroprotective function.
11PQQ roles in biological processesSystematic ReviewCited 99×2012
This review discusses different findings suggesting the versatility in PQQ functions and provides the most plausible intellectual basis to the ubiquitous roles of this compound in a large number of biological processes, as a nutrient and a perspective vitamin.
Misra HS et al. · Journal of biosciences (2012)
This review covers the comprehensive information on various aspects of PQQ known till date.
Most recent findings correlating the exceptionally high redox recycling ability of PQQ to its potential as anti-neurodegenerative, anticancer and pharmacological agents, and as a signalling molecule have been distinctly brought out.
This review discusses different findings suggesting the versatility in PQQ functions and provides the most plausible intellectual basis to the ubiquitous roles of this compound in a large number of biological processes, as a nutrient and a perspective vitamin.
Microbial metabolites including short chain fatty acids as well as other molecules such as pyrroloquinoline quinone, fermentation gases, and modified fatty acids influence mitochondrial function.
Bajpai P et al. · Mitochondrion (2018)
Microbial metabolites including short chain fatty acids as well as other molecules such as pyrroloquinoline quinone, fermentation gases, and modified fatty acids influence mitochondrial function.
This review focuses on the known direct and indirect effects of microbes upon mitochondria and speculates regarding additional links for which there is circumstantial evidence.
Overall, while there is compelling evidence that a microbiota-mitochondria link exists, explicit and holistic mechanistic studies are warranted to advance this nascent field.
Redox-active compounds such as resveratrol, pyrroloquinoline quinone, and hydroxytyrosol can potently counteract reactive oxygen species, and improve mitochondrial function and biogenesis.
Cheng Z et al. · Molecular nutrition & food research (2014)
Therefore, targeting the mitochondrial alterations with these redox-active compounds may lead to new therapeutic or preventive options for T2DM.
In this article, we review the molecular mechanisms of mitochondrial alterations in T2DM, and the action of redox-active compounds to reverse mitochondrial changes and oxidative stress in T2DM.
In addition, the current challenges and future directions are discussed and prospected.
In summary, PQQ is a promising molecule with broad potential health benefits, impacting human health from cellular metabolism to disease prevention and treatment, positioning it as a key player in nutritional science and public health.
Yan T, Nisar MF, Hu X, Chang J, Wang Y, Wu Y, Liu Z, Cai Y, Jia J, Xiao Y, Wan C. · Current research in food science (2024)
The safety of PQQ has been established, with no reported toxicity or genotoxicity in various studies, and it is considered a safe nutritional supplement.
Future research directions should focus on determining the optimal dosages of PQQ for specific health outcomes and assessing its long-term effectiveness and safety.
The translation of PQQ research into clinical practice could offer new strategies for managing metabolic disorders, enhancing cognitive health, and potentially extending lifespan.
15Cognitive functionRCTCited 21×n=58 · small study2022
Study demonstrates that supplementation of PQQ disodium salt is useful in improving memory, attention, judgment, and cognitive function, in middle-aged to elderly population, who feel they have become more forgetful because of aging.
Shiojima Y et al. · Journal of the American Nutrition Association (2022)
Significant improvements were observed on the Cognitrax's cognitive function domain score on "composite memory", "verbal memory", "reaction time", "complex attention", "cognitive flexibility", "executive function", and "motor speed" in the mnemoPQQ® group as compared to the placebo group.
The DECO and the MMSE-J scores were also significantly improved in the mnemoPQQ® group.
Study demonstrates that supplementation of PQQ disodium salt is useful in improving memory, attention, judgment, and cognitive function, in middle-aged to elderly population, who feel they have become more forgetful because of aging.
16Effects on alcohol metabolism and oxidative stress markersRCTCited 7×n=20 · very small study2024
After the administration of Si.Pi.Mi, the data seemed to suggest a better alcohol metabolism and oxidative balance in response to wine intake.
Bosco G et al. · Nutrients (2024)
Huge benefit
← WorseNo effectBetter →
Si.Pi.Mi intake reduced circulating ethanol after 120 min (-33%).
Changes in oxidative stress biomarkers, particularly a TAC (range +9-12%) increase and an 8-isoprostane (marker of lipidic peroxidation) decrease (range -22-27%), were observed too.
After the administration of Si.Pi.Mi, the data seemed to suggest a better alcohol metabolism and oxidative balance in response to wine intake.
17Cerebral oxygenation saturationRCTCited 7×n=34 · small study2024
Despite the limited number of participants included in the study for interpreting clinical parameters, the dihydrogen-PQQ mixture blend shows promise as a potential dietary intervention for enhancing mental orientation and brain metabolism in individuals with age-related mild cognitive decline.
Baltic S et al. · The journal of nutrition, health & aging (2024)
Noticeable benefit
← WorseNo effectBetter →
Likely real
Cerebral oxygenation saturation exhibited a significant increase following the administration of the dihydrogen-PQQ mixture, from 48.4 ± 7.2% at baseline to 52.8 ± 6.6% at 6-week post-administration (P = 0.005).
In addition, brain N-acetyl aspartate levels significantly increased at seven out of thirteen locations post-intervention in participants receiving the mixture (P ≤ 0.05).
Despite the limited number of participants included in the study for interpreting clinical parameters, the dihydrogen-PQQ mixture blend shows promise as a potential dietary intervention for enhancing mental orientation and brain metabolism in individuals with age-related mild cognitive decline.
In the logistic regression analysis that included the results of all cognitive tests, the changes due to PQQ intake were observed at 8 and 12 weeks in the young and old groups, respectively.
Tamakoshi M et al. · Food & function (2023)
A further age-stratified analysis was performed.
In younger adults (aged 20-40 years), PQQ improved cognitive function (cognitive flexibility, processing speed, and execution speed) after 8 weeks.
Only older adults (aged 41-65 years) showed improvements in complex and verbal memory after 12 weeks.
19LDL cholesterol reductionRCTCited 16×n=29 · very small study2015
Our study findings suggest that PQQ suppressed the LDL-chol level, which is an important finding, because a high level of this lipid is a risk factor for various lifestyle-related diseases.
Nakano M et al. · Journal of nutritional science and vitaminology (2015)
Noticeable benefit
← WorseNo effectBetter →
After 12 wk, the mean serum TG levels had not changed; however, a marginally significant decrease in the mean LDL-chol (from 136.1 to 127.0 mg/dL) was observed in the PQQ group.
In eleven volunteers out of 29, serum low-density lipoprotein cholesterol (LDL-chol) levels at baseline were high (≥140 mg/dL).
In the stratification analysis of the high LDL-chol subgroup (baseline LDL-chol level ≥140 mg/dL), the mean LDL-chol levels decreased significantly from the baseline values in the PQQ group compared to the placebo group.
Furthermore, the PQQ group had higher PGC-1α protein levels after 6 weeks of endurance training compared to PLC (p < 0.05).Conclusions: Supplementation of PQQ does not appear to elicit any ergogenic effects regarding aerobic performance or body composition but appears to impact mitochondrial biogenesis by way of significant elevations in PGC-1α protein content.
Hwang PS et al. · Journal of the American College of Nutrition (2020)
However, there were significant improvements in peak oxygen consumption (VO2peak) and total exercise test duration after endurance-training, irrespective of group (p < 0.05).
The PQQ group had a significant increase in PGC-1α protein levels from baseline to post endurance training compared to PLC (p < 0.05).