Skip to main content
Evidence Library

Scientific References

The research behind Metabolicum's evidence-based approach

How We Evaluate Evidence

Not all research is equal. We assign confidence grades to each source based on study design, sample size, replication status, and methodology. This helps you understand how confident you can be in each finding.

Click any grade to learn more

Grade A

High Confidence

Replicated findings across multiple well-designed studies

Grade B

Good Confidence

Well-designed single studies with strong methodology

Grade C

Moderate Confidence

Observational data with consistent patterns

Grade D

Emerging Evidence

Mechanistic or theoretical - interpret cautiously

Grade E

Clinical Consensus

Practitioner experience without formal trials

Understanding the Reproducibility Crisis

Why are we so careful about evidence grading? Because a significant portion of published research fails to replicate.

StudyFindingGrade
Begley & Ellis, 2012Only 21% of landmark cancer studies could be replicatedA
Open Science Collaboration, 2015Only 36% of psychology studies replicatedA
Ioannidis, 2005Theoretical framework explaining why most findings are falseA

This doesn't mean you should distrust all research. It means:

  • •Single studies warrant caution — Replication matters
  • •Peer review is necessary but not sufficient — Many peer-reviewed findings are later overturned
  • •Effect size matters more than p-values — Statistical significance ≠ practical importance
  • •Longer studies are generally more reliable — Short-term biomarker changes may not reflect long-term outcomes

We grade evidence honestly so you can calibrate your confidence appropriately.

Research Library

In-depth analysis of foundational studies with translated summaries

Showing studies cited on: AIP Calculator

Showing 4 studies

How We Use References

In Calculators

Primary thresholds come from Grade A sources. When Grade A evidence suggests a range rather than a single value, we present the range with context.

In Educational Content

We draw on Grades A-C for educational claims, clearly labeling evidence quality. Grade D and E content is marked as theoretical or practitioner-derived.

In Paradigm Frameworks

  • Standard Medical: Grade A (established guidelines)
  • Research Consensus: Grade A-B (outcome research)
  • Metabolic Optimization: Grade B-E (intervention research + clinical consensus)

Related Pages

Evidence Grades

Grade A: High ConfidenceReplicated findings across multiple studiesGrade B: Good ConfidenceWell-designed single studiesGrade C: Moderate ConfidenceObservational data with consistent patternsGrade D: Emerging EvidenceMechanistic or theoreticalGrade E: Clinical ConsensusPractitioner consensus

Other Pages

Our MethodologyHow we approach health informationFour Clinical FrameworksWhy we show multiple interpretations
Our Methodology

This bibliography contains the research supporting Metabolicum's evidence-based approach.

Last comprehensive review: December 2025