A
Petersen 2018: Mechanisms of Insulin Action and Insulin Resistance
Petersen & Shulman • Physiological Reviews • 2018
Ectopic lipid in liver and muscle is the primary driver of insulin resistance
Insulin Resistancemetabolismmolecular mechanisms
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.
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.
| Study | Finding | Grade |
|---|---|---|
| Begley & Ellis, 2012 | Only 21% of landmark cancer studies could be replicated | A |
| Open Science Collaboration, 2015 | Only 36% of psychology studies replicated | A |
| Ioannidis, 2005 | Theoretical framework explaining why most findings are false | A |
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: Insulin Resistance
Showing 4 studies
Review Article
B
Freeman 2023: Insulin Resistance - Clinical Overview
Freeman et al. • StatPearls Publishing • 2023
HOMA-IR is the most practical clinical tool for assessing insulin resistance
Insulin Resistanceclinical assessmenttreatment
A
Hallberg 2018: Virta Health Type 2 Diabetes Reversal
Hallberg et al. • Diabetes Therapy • 2018
60% achieved diabetes reversal while 94% reduced or eliminated insulin
Insulin Resistancediabetes reversalketogenic diet+1 more
A
Sutton 2018: Time-Restricted Eating Improves Insulin Sensitivity
Sutton et al. • Cell Metabolism • 2018
Early 6-hour eating window improved insulin sensitivity by 36% without weight loss
Insulin Resistancetime restricted eatingcircadian rhythm+1 more
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
This bibliography contains the research supporting Metabolicum's evidence-based approach.
Last comprehensive review: December 2025