CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-09). The draft was written by AI, the existence of all 7 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 138 · Search date 2026-07-09 · Methodology v0.6

PQQ,
does it really help with Energy and cognition?

30-Second Summary
C
Evidence Grade C · 47 · Safety caution
Cognition C (58), energy D (33), combined C (47)
What the
research shows
For cognition, three manufacturer-linked randomized double-blind placebo-controlled trials reported limited positive findings. For energy, evidence of improvement in objective aerobic performance is insufficient.
What the
ads claim
Advertising emphasizes 'mitochondrial booster,' 'cellular energy,' 'antioxidant,' 'brain energy,' and 'synergy with CoQ10.' A substantial part of these expressions is closer to mechanistic or surrogate-marker evidence.
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Useful facts when choosing a product

  • Commercial doses of 10-20 mg/day are common, and many studies are also in this range.
  • Safety data should be distinguished by ingredient form, such as PQQ disodium salt.
  • Mitochondrial biogenesis and inflammation markers are not the same as clinical fatigue or cognitive improvement.
  • Long-term high-dose safety data are limited.
Gap Measurement · Verdict 138 · C 47
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Itoh 2016 (PMID 26782228) was a randomized double-blind placebo-controlled trial in healthy older adults that administered BioPQQ 20 mg/day for 12 weeks. It reported limited positive findings for selective attention and working memory on tests including Stroop/reverse-Stroop and visuospatial tests, and was linked to Mitsubishi Gas Chemical, the manufacturer of BioPQQ. Shiojima 2022 (PMID 34415830) was a parallel-group trial with N=64 enrolled/58 completed that administered mnemoPQQ 21.5 mg/day for 12 weeks. It reported positive findings on Cognitrax measures including memory, attention, and reaction time and on MMSE-J; many authors were employees of the sponsor Ryusendo, the seller of mnemoPQQ. Tamakoshi 2023 (PMID 36807425) was an N=70/62 trial that administered BioPQQ 20 mg/day for 12 weeks and reported positive composite and verbal memory findings. The younger subgroup analysis carries multiplicity risk, and Mitsubishi Gas Chemical fully funded the trial. In the energy evidence, Hwang 2020 (PMID 31860387) assigned N=23 to PQQ 20 mg plus six weeks of endurance training; VO2peak and time to exhaustion did not differ from placebo, while only the PGC-1α surrogate marker increased. Nascent Health, the manufacturer and supplier of PureQQ, supported the study. Nakano 2012 was an uncontrolled, open-label, single-arm trial with N=17 that reported improvements in subjective POMS fatigue, vigor, and sleep questionnaires and was linked to BioPQQ. Harris 2013 (PMID 24231099) was a small N=10 crossover study of surrogate markers including CRP, IL-6, and mitochondrial metabolites, not clinical energy endpoints. The EFSA novel food review (DOI 10.2903/j.efsa.2017.5058) is safety material, not efficacy evidence.

02

Why this is classified as C (47)

Methodology boundary rule ②-b was applied. Cognition is not ungraded because three double-blind placebo-controlled RCTs using objective cognitive tests reported positive findings, but all were manufacturer-linked, small, and lacked non-manufacturer independent replication; cognition is therefore capped at C, yielding C (58). Energy is D (33) because the RCT was null for objective aerobic performance and the remaining evidence consists of subjective questionnaires or surrogate markers. The combined judgment is C (47).

Counterpoint. The EFSA novel food safety review concerns conditions of use for a specific ingredient and is not included as efficacy evidence. Positive findings from the cognition trials are also distinct from replication in manufacturer-independent studies of PQQ alone.

Rejudgment record. Reassessment (?→C) — Positive cognition DBPC RCTs exist, but all are manufacturer-linked and lack independent replication, so rule ②-b caps cognition at C; energy is D because the objective performance RCT was null; combined grade C.

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
CognitionC · 58Three positive double-blind RCTs on objective cognition, but all manufacturer-linked, small, and without independent replication (rule 2-b)
EnergyD · 33The objective aerobic-performance RCT was null (Hwang 2020); the rest is subjective questionnaires and surrogate markers

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Itoh et al. 2016 (PMID 26782228)Randomized double-blind placebo-controlled trial, 12 weeksLinked to Mitsubishi Gas Chemical, the manufacturer of BioPQQObjective cognitive tests including Stroop/reverse-Stroop and visuospatial testsLimited positive findings for selective attention and working memory with BioPQQ 20 mg/dayCognition grade C evidence; manufacturer-linked with no independent replication
Shiojima et al. 2022 (PMID 34415830)Randomized double-blind placebo-controlled parallel-group trial, 12 weeks58Many authors were employees of the sponsor Ryusendo, the seller of mnemoPQQCognitrax memory, attention, reaction time, and other measures, plus MMSE-JPositive cognitive-test findings with mnemoPQQ 21.5 mg/dayCognition grade C evidence; clear manufacturer conflict of interest and no independent replication
Tamakoshi et al. 2023 (PMID 36807425)Randomized double-blind placebo-controlled trial, 12 weeks62Fully funded by Mitsubishi Gas Chemical, the manufacturer of BioPQQComposite and verbal memory; younger subgroup analysisPositive findings with BioPQQ 20 mg/day; the younger subgroup analysis carries multiplicity riskCognition grade C evidence; manufacturer-linked with no independent replication
Hwang et al. 2020 (PMID 31860387)Randomized double-blind placebo-controlled trial with six weeks of endurance training23Supported by Nascent Health, the manufacturer and supplier of PureQQVO2peak, time to exhaustion, and PGC-1αWith PQQ 20 mg/day, objective aerobic performance did not differ from placebo; only the PGC-1α surrogate marker increasedEnergy grade D evidence; null objective performance, positive surrogate marker, and manufacturer support
Nakano et al. 2012 (DOI 10.31989/ffhd.v2i8.81)Open-label single-arm trial without placebo control17Linked to BioPQQSubjective POMS fatigue, vigor, and sleep questionnairesReported questionnaire improvements; not an objective energy endpointSupporting energy grade D evidence; subjective questionnaires, uncontrolled, and manufacturer-linked
Harris et al. 2013 (PMID 24231099)Small crossover study10The reported funding source was not separately verified in the materials used for this judgmentSurrogate markers including CRP, IL-6, and mitochondrial metabolitesEvaluated changes in surrogate markers, not clinical energy endpointsSupporting energy grade D evidence; surrogate markers and small sample
EFSA NDA Panel 2017 (DOI 10.2903/j.efsa.2017.5058)Novel food regulatory safety reviewRegulatory assessment materialSafety of PQQ disodium salt under specified conditions of useA safety review that did not evaluate efficacyRule ④ regulatory neutrality; not efficacy evidence
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Receipt — 7 References

All 7 cited sources were verified for existence at the original page (as of 2026-07-09).

Itoh Y, et al. 2016. PMID 26782228.
checked
Shiojima Y, et al. 2022. PMID 34415830.
checked
Tamakoshi M, et al. 2023. PMID 36807425.
checked
Hwang PS, et al. 2020. PMID 31860387.
checked
Nakano M, et al. 2012. DOI 10.31989/ffhd.v2i8.81.
checked
Harris CB, et al. 2013. PMID 24231099.
checked
EFSA NDA Panel. 2017. Safety of pyrroloquinoline quinone disodium salt as a novel food. DOI 10.2903/j.efsa.2017.5058.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-09 · Corrections: 1

Correction log — 1

Corrections applied to this verdict, in chronological order. Changes are logged, not erased.

  • 2026-07-11 · Re-adjudication (grade changed) — The previous 'judgment deferred (?)' cited a lack of confirmatory RCTs with objective endpoints for energy/cognition, but three double-blind placebo-controlled RCTs using objective cognitive tests exist (Itoh 2016 PMID 26782228, Shiojima 2022 PMID 34415830, Tamakoshi 2023 PMID 36807425), all positive. Because human RCTs exist, this is C, not '?'. However, all positive cognition trials are manufacturer-linked (BioPQQ/mnemoPQQ), small, and lack independent replication, so cognition is capped at C by rule 2-b; the objective aerobic-performance RCT for energy was null (Hwang 2020), making energy D. The three cognition RCTs are now cited explicitly and the EFSA search link was replaced with the actual reference. 2026-07-11 internal audit. (grade ?→C)

Cite this verdict

PQQ x energy and cognition Evidence Grade C card
[Chamgap] PQQ x energy and cognition — Evidence Grade C·47. 7 cited sources checked. Source: https://chamgap.com/en/verdicts/energy/pqq-energy-cognition/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.