The research behind Metabolicum's evidence-based approach
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.
High Confidence
Replicated findings across multiple well-designed studies
Good Confidence
Well-designed single studies with strong methodology
Moderate Confidence
Observational data with consistent patterns
Emerging Evidence
Mechanistic or theoretical - interpret cautiously
Clinical Consensus
Practitioner experience without formal trials
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:
We grade evidence honestly so you can calibrate your confidence appropriately.
In-depth analysis of foundational studies with translated summaries
Showing 5 studies
Bedogni G, et al. • BMC Gastroenterology • 2006
FLI <30 rules out fatty liver (negative LR=0.2, sensitivity 87%); FLI ≥60 rules in fatty liver (positive LR=4.3, specificity 86%).
Zelber-Sagi S, et al. • Journal of Hepatology • 2018
High red meat consumption was independently associated with NAFLD (OR 1.47) and insulin resistance, with cooking method (high-temperature grilling) adding additional risk.
Gastaldelli A, et al. • Hepatology • 2009
Subjects with FLI >60 had IMT of 0.64±0.08 mm vs 0.58±0.08 mm in FLI <20. FLI correlated with CHD risk (r=0.48) and inversely with insulin sensitivity (r=-0.43).
Younossi ZM, et al. • Hepatology • 2016
Global NAFLD prevalence is 25.24% (95% CI: 22.10-28.65%). Associated comorbidities: obesity 51%, hyperlipidemia 69%, hypertension 39%, type 2 diabetes 23%.
Browning JD, et al. • Hepatology • 2011
Carbohydrate restriction reduced liver fat by 42% in just 2 weeks, compared to 25% with caloric restriction alone, despite similar total weight loss.
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.
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.
This bibliography contains the research supporting Metabolicum's evidence-based approach.
Last comprehensive review: December 2025