Evidence Updates

What changed, and why.

A grade that never moves isn't rigorous — it's just old. This is the dated, public record of every change we've made to an ingredient's evidence status, with the reasoning attached. Downgrades included; especially downgrades.

20 logged changesLast update July 12, 2026Subscribe via RSS

July 12, 2026

10 changes
  • New profile5-HTPEvidence: Grade C

    New profile at Grade C, with explicit serotonergic-interaction cautions.

    Prompted by: Sleep & recovery cluster expansion.

  • New profileChamomileEvidence: Grade C

    New profile at Grade C for sleep/relaxation, on limited human data.

    Prompted by: Sleep & recovery cluster expansion.

  • New profileL-TryptophanEvidence: Grade C

    New profile at Grade C for sleep/mood-adjacent roles, with conservative interaction cautions.

    Prompted by: Sleep & recovery cluster expansion.

  • New profileMagnesium GlycinateEvidence: Grade C

    New profile at Grade C — a well-tolerated, well-absorbed magnesium form with limited direct human cognition/sleep trials at this specific form.

    Prompted by: Sleep & recovery / micronutrient batch.

  • New profileMelatoninEvidence: Grade B

    New profile, published at Grade B on independent (non-sponsor) evidence: a meta-analysis of 19 randomized trials found melatonin reduced sleep-onset latency and modestly increased total sleep time. Graded for sleep onset specifically — not as a daytime nootropic.

    Prompted by: Sleep & recovery cluster expansion; new Hormone category.

  • New profilePassionflowerEvidence: Grade C

    New profile at Grade C for sleep/relaxation, on limited human data.

    Prompted by: Sleep & recovery cluster expansion.

  • Graded outSeleniumGraded Out

    Published straight into Graded Out on a safety-and-null-evidence basis. Randomized trials in replete older adults show no cognitive or dementia-prevention benefit (SELECT, PREADViSE), and the window between adequate and excessive intake is narrow.

    Prompted by: Micronutrient batch review.

  • New profileValerianEvidence: Grade C

    New profile at Grade C for sleep; trials are mixed and heterogeneous in preparation.

    Prompted by: Sleep & recovery cluster expansion.

  • Graded outVitamin EGraded Out

    Published straight into Graded Out on a safety veto. In replete adults the cognitive-prevention evidence is null (PREADViSE), and high-dose supplementation carries a documented safety signal — repletion of a true deficiency is not a nootropic effect.

    Prompted by: Micronutrient batch review.

  • New profileZincEvidence: Grade C

    New profile at Grade C — essential for cognition when deficient, but supplementation in replete adults is a repletion story, not a nootropic one.

    Prompted by: Micronutrient batch review.

July 11, 2026

6 changes
  • Grade changeAmerican GinsengEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. Acute cognitive effects appear in small trials but do not replicate consistently enough across doses and populations to hold a B.

    Prompted by: Full-library evidence & data refresh.

  • Grade changeCurcumin (lipidated)Evidence: Grade BEvidence: Grade C

    Downgraded from B to C. The cognition signal comes from a small number of trials with a specific bioavailable form; the broader, independent replication needed for a B is not there yet.

    Prompted by: Full-library evidence & data refresh.

  • Grade changeLutein + ZeaxanthinEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. Cognitive-benefit trials are promising but limited in number and largely in specific populations, short of the consistent replication a B requires.

    Prompted by: Full-library evidence & data refresh.

  • Grade changeResveratrolEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. Acute dosing raises cerebral blood flow but did not improve cognition in healthy adults; the only positive cognition data come from a narrower postmenopausal-women population.

    Prompted by: Full-library evidence & data refresh.

  • Grade changeSpearmint ExtractEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. The working-memory effect is real in the trials that exist but rests on a single branded extract with limited independent replication.

    Prompted by: Full-library evidence & data refresh.

  • Grade changeZynamiteEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. The attention/memory result rests on a single acute-dose trial in healthy adults; a B needs independent replication that does not yet exist.

    Prompted by: Full-library evidence & data refresh.

July 7, 2026

4 changes
  • Graded outDMAEEvidence: Grade CGraded Out

    Graded out, not merely low-graded. The strongest human data are 1960s–70s pediatric trials since abandoned; there are essentially no adequate positive RCTs for memory or focus in healthy adults, and the acetylcholine mechanism is not well substantiated.

    Prompted by: Full-library evidence audit.

  • Grade changePanax GinsengEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. Acute cognitive effects appear in some trials but replicate inconsistently across doses and extracts, so the evidence is limited rather than moderate.

    Prompted by: Full-library evidence audit.

  • Grade changePhosphatidylserineEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. The stronger data sit in age-related decline and soy-derived PS trials; the healthy-adult, focus-specific evidence at label-realistic doses is thinner than a B implies.

    Prompted by: Full-library evidence audit.

  • Grade changeRhodiola RoseaEvidence: Grade BEvidence: Grade C

    Downgraded from B to C. The human trials are mostly small, short, and heterogeneous in outcome measure, and several are sponsor-linked — not enough consistent, independent replication to hold a B.

    Prompted by: Full-library evidence audit; introduction of the Graded Out status.

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