Metabolic & Cardiometabolic

PCOS increases NAFLD

Leans support(causal-association-only) Metabolic & Cardiometabolic 🔬 Includes disconfirming

RefutedContestedStrong support

consensus score 0.68

🔬 Capped to leans support — causal-association-only evidence only. The raw signal looked like strong support, but a claim about human health can't be graded that high on animal or lab evidence alone. It stays capped until human trials weigh in.

📅 Last reviewed: 2026-07-15 ⓘ

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

5 support 1 contradict 0 tested null 2 mixed · 8 sources, 6 independent groups

What the evidence shows

PCOS increases the prevalence/risk of NAFLD (fatty liver).

The evidence (8)

Source	Grade	Stance	Quality	Finding
Liu D, Gao X, Pan XF, et al. 2023 · BMC Med	observational	contradicts	moderate	Bidirectional two-sample MR: genetically-predicted NAFLD RAISES PCOS risk (OR 1.08, 95% CI 1.02-1.14, p=0.009), but full text states 'little evidence for a causal effect of genetically predicted PCOS on NAFLD risk', consistent across replication and sensitivity analyses. Argues the causal arrow runs NAFLD->PCOS, not the reverse.
uk-nafld-2018 2018	observational	supports	high	UK primary-care cohort (landmark): PCOS -> increased NAFLD incidence; androgen excess implicated.
Shengir M, et al. 2021 · JGH Open	meta-analysis	supports	moderate	NAFLD significantly more prevalent in premenopausal PCOS vs controls.
Devas N et al 2026 · study_type: observational	observational	mixed	moderate	Retrospective, n=885 (286 PCOS+MASLD, 521 MASLD-only, 78 male-MASLD). PCOS group diagnosed MASLD younger + higher BMI, but BMI/age-adjusted analysis: PCOS NOT independently assoc. w/ worse fibrosis; propensity-matched PCOS actually had LOWE
Amiri F et al 2025 · study_type: observational	observational	mixed	moderate	Case-control, non-obese women, n=86 PCOS vs 86 controls. Mild-moderate fatty liver more prevalent in PCOS vs controls (P=0.04). Total cholesterol-PCOS correlation became statistically insignificant after BMI adjustment.
Yao K, Zheng H, Peng H 2023 · Endokrynol Pol	meta-analysis	supports	moderate	Meta-analysis: PCOS associated with NAFLD, OR 2.93 (95% CI 2.38-3.62) - but I2 = 83.7%, substantial heterogeneity tempering precision.
Manzano-Nunez R, Santana-Dominguez M, Rivera-Esteban J, et al. 2023 · J Clin Med	meta-analysis	supports	moderate	SR/MA of 36 studies: pooled NAFLD prevalence in PCOS 43% (95% CI 35-52%), high heterogeneity; meta-regression modelled prevalence against risk factors. Prevalence-level evidence, not causal.
nafld-nonobese-2017 2017	observational	supports	moderate	Case-control (non-obese women): PCOS with hyperandrogenism is a NAFLD risk factor even in non-obese — isolates androgen effect from obesity.

Disagree, or know a study we missed?

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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.