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Randomized trial · measured the question itself

12-week trial of lion's mane: one memory test improved, two did not

Saitsu and colleagues · Biomedical research (Tokyo, Japan) · 2019

Original title: Improvement of cognitive functions by oral intake of Hericium erinaceus.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

Mixed

Three tests were done. On the Mini Mental State Examination alone, scores were better with lion's mane. The other two tests (Benton visual retention, verbal paired-associate learning) are not reported as better.

The study at a glance

Type of study
Randomized trial
Who or what was studied
Adults tested for memory and thinking (number and age not given in abstract)
What was tested
Supplement made from lion's mane fruiting body for 12 weeks, vs placebo
What it measured
The question itself: memory and thinking
How long
12 weeks
Who has a stake
No disclosure in PubMed
No disclosure in PubMed.
Journal
Biomedical research (Tokyo, Japan), 2019
Source
PubMed record 31413233. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • ✓Compared with a placebo, a dummy treatment.
  • •The abstract does not say how many people took part.
  • •Lasted 12 weeks.
  • ✓Measured the question itself: memory and thinking.
  • •The PubMed record has no conflict-of-interest statement.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: memory and thinking

    4

    1 benefit, 3 mixed

    ↑ This study is the ringed dot

  2. Trials in people: other measures

    0

    None among the papers we read.

  3. Trials in people: lab tests or safety

    0

    None among the papers we read.

  4. Population studies

    0

    None among the papers we read.

  5. Blood levels and genes

    0

    None among the papers we read.

  6. Animals

    1

    1 no difference

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does lion's mane improve memory?”

Unclear. Only four trials, with mixed results.

Confidence: very low. Based on 6 on-topic papers.

Read the full answer

Of the other 3 papers on the same step: 1 benefit, 2 mixed. This one found mixed. It agrees with most of them.

  • Quoted in “What we found”: Only 14 papers exist on this question. Four are human trials of memory or thinking; the two that report size had 30 and 41 people.
  • Part of the finding “Longer trials: gains on some memory tests”.
  • Marked as a key paper in the research timeline: Second longer trial; better on one of three tests.
  • Open item for a person: Menon review Menon 2025 pooled one trial and one pilot trial; these may be Mori Mori 2009 or Saitsu Saitsu 2019. Check for double counting.
  • Open item for a person: Saitsu Saitsu 2019 and La Monica La Monica 2023 abstracts give no number of people or ages; Saitsu gives no dose. Check full texts.
  • Open item for a person: Mori Mori 2009 and Saitsu Saitsu 2019 have no conflict statement in PubMed, so company ties are unknown.

Other papers on the same step

See all 6 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The two reads differed. The reviewer checked the abstract and kept the first read. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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