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.
Vitamin B12
Selected research topic
Stress and mood
The comparison is unconfirmed, so the findings cannot establish this ingredient’s effect.
Findings from a combination study cannot be attributed to this ingredient alone.
Some publications still need interpretation checks and are kept separate from the findings below.
- Publications for this topic
- 3
- Human comparison publications
- 0
- Publications needing review
- 1
Findings in the studies
depression
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.
Measurement and study conditions
- Study type
- Meta-analysis
- Study population
- Study subject not identified
- Ingredients tested
- Unknown intervention
- How results were compared
- Study comparison: Observational dietary intake/status association as reported; this source does not establish a contro
- Measurement time
- varied across included observational studies
measures of depression
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.
Several ingredients were tested together, so this ingredient’s individual effect is unknown.
Combination study · varied across included trialsMeasurement and study conditions
- Study type
- Meta-analysis
- Study population
- Recorded population category: General population. Whether the research involved humans needs confirmation.
- Ingredients tested
- Ingredient combination
- How results were compared
- Study comparison: Pooled review of B12 alone and B-complex randomized trials; comparator details not reported in the a
- Additional measurement information
- Primary outcome
- Measurement time
- varied across included trials
Representative outcome and study details
Studies with an unspecified organism reported a change with no confirmed comparison group in depression.
Scope not specified · Population not specified · comparator not confirmed
1 publications linked to this result
- Route, form, dose, or population details are incomplete, so the findings cannot be confirmed as directly comparable.
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: B
The 57.4 evidence score includes 1 independent human studies and 1 clinical studies in the representative benefit area. The B tier remains conservative because of the evidence centers on contextual or measured outcomes rather than general-use effects, limited repetition across independent human clinical studies.
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: 96
Papers linked to this topic 3 · distinct papers 3 · comparison findings need further review · papers needing additional review 1
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.
- depression: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- measures of depression: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
What the research found
depression
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Unknown intervention · Unspecified population
Analysis coverage and paper counts
1 paper · 1 measured outcome
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.
measures of depression
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Ingredient combination · General population
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
Analysis coverage and paper counts
1 paper · 1 measured outcome
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.
Review · Unknown intervention · 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.
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.
Cautions reported with another supplement or medication
These studies reported worsening outcomes, reduced absorption, or other cautions with combined use. They do not predict an individual's outcome.
AntacidsAntacids may alter vitamin B12 absorption and utilization, increasing deficiency risk.
MetforminMetformin-treated T2DM patients are at higher risk of vitamin B12 deficiency and more severe neuropathy symptoms; supplementation may prevent or treat these conditions.
Proton pump inhibitorsPPI use may impact the absorption of vitamin B12, resulting in a slightly increased risk of deficiency.