Panax ginseng and memory: grade C

Limited evidence. Direction: Benefit.

C LimitedShort-term onlySingle research group

Educational guidance, not medical advice

Why this grade

Rubric condition met: C: small crossover RCTs in healthy adults with mixed results; the only pooled memory estimate mixes healthy and clinical populations

A 2024 meta-analysis of 15 RCTs (671 participants) found a small memory effect (SMD 0.19) but no effect on overall cognition, attention or executive function, and it pooled healthy people with clinical groups. The 2010 Cochrane review (searched 2009) found no convincing evidence of cognitive enhancement in healthy participants and could not pool trials. The healthy-adult trials are small acute crossover studies, mostly from one research group using one branded extract (G115), with memory gains at some doses and attention costs at others. B was not met because no pooled estimate in healthy adults exists.

How we grade evidence

Studies this grade rests on

each study this grade rests on, by publication year and design. Solid: effect versus the comparator; half-filled: mixed; hollow: no effect; dashed: result not recorded yet. Larger marks had more participants.

Show the numbers

Study	Year	Design	Participants	Result
Kennedy 2001	2001	crossover RCT	20	result not recorded
Reay 2010	2010	crossover RCT	30	result not recorded
Geng 2010	2010	systematic review	not recorded	result not recorded
Zeng 2024	2024	meta-analysis	671	result not recorded

Panax ginseng (G115) improves aspects of working memory performance and subjective ratings of calmness in healthy young adults.

Reay JL, Scholey AB, Kennedy DO. Panax ginseng (G115) improves aspects of working memory performance and subjective ratings of calmness in healthy young adults Hum Psychopharmacol, 2010. PMID 20737519

Result not recorded

Design: Placebo-controlled, double-blind, randomised crossover trial (8 days per treatment)
Sample: n = 30
Population: Healthy young adults (mean age 22.87)
Funding: not stated in PubMed or Crossref records

Dose dependent changes in cognitive performance and mood following acute administration of Ginseng to healthy young volunteers.

Kennedy DO, Scholey AB, Wesnes KA. Dose dependent changes in cognitive performance and mood following acute administration of Ginseng to healthy young volunteers Nutr Neurosci, 2001. PMID 11842896

Result not recorded

Design: Placebo-controlled, double-blind, balanced crossover trial
Sample: n = 20
Population: Healthy young adults
Funding: not stated in PubMed or Crossref records; extract G115 named as supplied by Pharmaton SA in the abstract

Ginseng for cognition.

Geng J, Dong J, Ni H. Ginseng for cognition Cochrane Database Syst Rev, 2010. PMID 21154383

Result not recorded

Design: Cochrane systematic review of 9 randomized, double-blind, placebo-controlled trials (5 analysed; no pooling)
Population: Healthy participants (8 of 9 trials) and one trial in age-associated memory impairment
Funding: not stated in PubMed or Crossref records

Effects of Ginseng on Cognitive Function: A Systematic Review and Meta-Analysis.

Zeng M, Zhang K, Yang J. Effects of Ginseng on Cognitive Function: A Systematic Review and Meta-Analysis Phytother Res, 2024. PMID 39474788

Result not recorded

Design: Systematic review and meta-analysis of 15 RCTs (PROSPERO CRD42024514231)
Sample: n = 671
Population: Mixed: healthy people and people with cognitive impairment, schizophrenia, Alzheimer's disease or in hospital
Funding: not stated in PubMed or Crossref records

Search and history

Search (November 11, 2026): ginseng[ti] AND (cognition[tiab] OR cognitive[tiab] OR memory[tiab]) AND (meta-analysis[pt] OR systematic review[pt])

November 11, 2026 Graded C (proposed): Proposed in the monograph draft
November 13, 2026 C to C (approved): Editor sign-off November 13, 2026: grade matches the editor-approved final page