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Structured research library

Complete Ergothioneine Study Database

Search verified records by design and topic. Every record exposes the finding, limitation and primary source.

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8 verified records7 human records0 fabricated citations

Showing 8 verified research records

Human RCT2025n = 147

The Effect of Ergothioneine Supplementation on Cognitive Function, Memory, and Sleep in Older Adults with Subjective Memory Complaints: A Randomized Placebo-Controlled Trial

Intervention
10 mg/day, 25 mg/day, or placebo
Duration
16 weeks

Finding: Supplementation increased plasma ergothioneine, but the primary composite-memory outcome did not show a significant treatment effect at 16 weeks. Selected secondary, subjective, or time-by-treatment signals were reported.

Important limitation: The primary cognitive outcome was null; an early within-group signal was not sustained; several positive findings were secondary, subjective, per-protocol, or within-group results.

Primary paper ↗Our interpretation →
Human RCT2024n = 19

Investigating the efficacy of ergothioneine to delay cognitive decline in mild cognitively impaired subjects: A pilot study

Intervention
25 mg, three times weekly
Duration
1 year

Finding: The ergothioneine group improved on a learning assessment and showed a different neurofilament-light trajectory than placebo; routine blood, kidney and liver safety markers did not change.

Important limitation: Very small pilot sample; exploratory outcomes; not adequate to establish prevention or treatment of cognitive decline.

PubMed ↗Our interpretation →
Human observational2025n = 1,344

Serum ergothioneine and risk of dementia in a general older Japanese population: the Hisayama Study

Intervention
No intervention; baseline serum ergothioneine
Duration
Median 11.2 years

Finding: Higher serum ergothioneine was associated with lower incidence of all-cause dementia, Alzheimer’s disease, and non-Alzheimer dementia after multivariable adjustment.

Important limitation: Observational exposure cannot establish causation or show that supplementation prevents dementia; residual confounding and reverse causation remain possible.

PubMed ↗Our interpretation →
Human RCT2025n = See full text

Estimation and Validation of an Effective Ergothioneine Dose for Improved Sleep Quality Using a Physiologically Based Pharmacokinetic Model

Intervention
5 or 10 mg/day in dose modeling; 8 mg/day vs placebo in validation
Duration
8–16 weeks

Finding: The 8 mg/day validation study reported a statistically significant improvement in subjective sleep quality versus placebo.

Important limitation: Subjective outcome; linked modeling and validation design; replication by independent groups is needed.

PubMed ↗Our interpretation →
Human observational2022n = 470

Low Plasma Ergothioneine Predicts Cognitive and Functional Decline in an Elderly Cohort Attending Memory Clinics

Intervention
No intervention; baseline plasma ergothioneine
Duration
Up to 5 years

Finding: Lower baseline plasma ergothioneine was associated with poorer baseline performance and faster decline in several cognitive and functional measures.

Important limitation: Observational design cannot show that low ergothioneine caused decline or that supplementation would alter outcomes.

PubMed ↗Our interpretation →
Human pharmacokinetic2017n = See full text

Administration of Pure Ergothioneine to Healthy Human Subjects: Uptake, Metabolism, and Effects on Biomarkers of Oxidative Damage and Inflammation

Intervention
Oral pure L-ergothioneine
Duration
Short-term pharmacokinetic study

Finding: Oral ergothioneine increased plasma and whole-blood levels and had low urinary excretion. Most biomarker changes were not statistically significant.

Important limitation: Small, short study designed mainly for uptake and pharmacokinetics—not clinical outcomes.

PubMed ↗Our interpretation →
Human RCT2024n = 80

Effects of an ergothioneine-rich Pleurotus sp. on skin moisturizing functions and facial conditions: a randomized, double-blind, placebo-controlled trial

Intervention
Pleurotus tablets providing 25 mg ergothioneine/day
Duration
12 weeks

Finding: The study reported between-group differences for selected skin-moisture and imaging outcomes at certain time points.

Important limitation: Multiple outcomes and time points; mushroom matrix rather than isolated ergothioneine; some authors were employed by the mushroom producer.

PubMed ↗Our interpretation →