Improvement after a supplement is not the same as a comparative result
Start with the comparison. A before-and-after change alone cannot isolate the contribution of an ingredient.
Manganese
Selected research topic
Cognition
Some publications still need interpretation checks and are kept separate from the findings below.
- Publications for this topic
- 6
- Human comparison publications
- 0
- Publications needing review
- 6
This result is held for interpretation. That does not mean research found no effect.
Outcome groups needing additional review (1)
- Working memory · Distinct papers needing additional review: 1Direction unclear: 1
One paper can appear under multiple measured outcomes or review reasons, so these counts should not be added together.
Representative outcome and study details
Some findings are held for review
Some papers have not cleared source or result review, so their findings are not summarized yet.
No confirmed result is available to summarize with study conditions.
1 publications linked to this result (1 awaiting review included)
- Those papers are not summarized until review is complete.
Data coverage and detailed study classifications
Paper counts are separated by research topic below. One paper may contribute to multiple findings.
Analysis status: Public-ready
Ingredient analysis date:
How the grade was determined: C
The 13.6 evidence score includes 0 independent human studies and 0 clinical studies in the representative benefit area. The C tier remains conservative because of limited repetition across independent human clinical studies, too few clinical findings with an explicit effect direction.
The grade is based mainly on the research area with the most evidence. It does not mean the same result was found in other areas.
Papers linked to this ingredient overall: 50
Papers linked to this topic 6 · distinct papers 6 · comparison findings need further review · papers needing additional review 6
A publication may appear in more than one count. These numbers should not be added. Ingredient-wide papers, topic-linked papers, and sources in outcome groups use different scopes. Adding source counts may count the same paper more than once.
- Working memory: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
What the research found
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Meta-analysis · Single ingredient · Unspecified population
The comparison could not be confirmed.
Analysis coverage and paper counts
3 papers · 3 measured outcomes
3 papers held from direction counts
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Other evidence · Single ingredient · Unspecified population
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Review · Single ingredient · Unspecified population
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Working memory
The study needs further checking before its result can be interpreted.
Other evidence · Single ingredient · Unspecified population
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
How to read research findings
How should I read research findings?
Research guidesNo clear difference and an uninterpretable result are different
A reported null comparison contains a result. An abstract without an interpretable comparison leaves a question unresolved.
Paper counts and study counts are different
Count original research separately from research that reanalyzes it. Publication volume is neither replication nor a quality rating.
Side effects and combination findings
Findings from this ingredient alone are shown separately from those involving another supplement or medication.
No reviewed caution rules are available yet. Reported caution findings are shown below.
Findings to review with care
Side effects reported for the ingredient alone are separated from findings involving another supplement or medication.
Side effects reported with this ingredient alone
Symptoms or adverse events reported in studies without another active ingredient.
oxidative stress1 papers
Manganese exposure induces oxidative stress leading to mitochondrial dysfunction, inflammation, and cytotoxicity, contributing to neurotoxicity.Animal studies · Systematic reviewManganese-induced neurotoxicity1 papers
EFSA Panel established a safe intake level of 8 mg/day for adults based on limited data, noting manganese-induced neurotoxicity as the priority adverse effect.Human studies · Systematic reviewdopaminergic dysfunction1 papers
Exposure to manganese is associated with dopaminergic dysfunction and Parkinsonian-like symptoms, indicating neurotoxic effects.Human studies · Systematic reviewdevelopmental neurotoxicity1 papers
Manganese is identified as a developmental neurotoxicant in epidemiological studies.Human studies · Systematic reviewWorking memory1 papers
Manganese exposure at excess levels is associated with significant working memory deficits and other neurological dysfunctions.Human studies · Systematic reviewBrain oxidative stress1 papers
Manganese overexposure can lead to neurotoxic effects such as oxidative stress and inflammation in the brain.Human studies · Systematic reviewBrain1 papers
Manganese at high dietary intake may be neurotoxic, particularly to the brain.Human studies · Systematic review