Worldwide, 13% of people have nonalcoholic fatty liver disease (NAFLD), a condition where fat accumulates in the liver not caused by alcohol.
See the scientific wording
The global prevalence of nonalcoholic fatty liver disease (NAFLD) is 13% among the general population.
Correlational — new studies may shift this
Observational2 moderate-quality studies link this claim to the outcome, but causation is not established.
What the research says
2 studies reviewedSupporting (2)
Systematic Review With Meta-AnalysisMeta-analysis2024
The study found that about 13% of children worldwide have NAFLD, which matches the number in the claim, but the claim is about all people, not just kids, so we don't know if 13% is true for adults too.
Computational/Algorithm StudyReview
This study found that worldwide, 13 out of every 100 people have fatty liver disease, which is exactly what the claim says.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 supporting studies
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