Healthy dietary patterns and metabolic dysfunction-associated fatty liver disease in less-developed ethnic minority regions: a large cross-sectional study

BACKGROUND: Little is known about the associations between healthy dietary patterns and metabolic dysfunction-associated fatty liver disease (MAFLD) in less-developed ethnic minority regions (LEMRs), where the prevalence of MAFLD is increasing rapidly and dietary habits are quite different from those in developed countries. Moreover, a significant subset of MAFLD individuals in LEMRs are nonobese, but the efficacy of dietary patterns on MAFLD individuals with different obese statuses is also unclear. We aimed to test the associations of two wildly recommended a priori dietary patterns—Alternate Mediterranean diet (AMED) and Dietary Approaches to Stop Hypertension (DASH)—with the risk of MAFLD in the total population, and further in nonobese and obese individuals. METHODS: We recruited 99,556 participants in the China Multi-Ethnic Cohort Study, an ongoing cohort study in less-developed southwest China. Using validated food frequency questionnaire, each participant was assigned an AMED score and a DASH score. MAFLD was ascertained as hepatic steatosis on ultrasound together with diabetes, overweight/obesity, or two other metabolic risk factors. We performed logistic regression with inverse probability of exposure weighting (IPEW) to examine associations between two dietary patterns and MAFLD, adjusting for potential confounders under the guidance of directed acyclic graphs. Further, analyses were stratified by body mass index. RESULTS: We included 66,526 participants (age 49.5±11.0; 62.6% women), and the prevalence of MAFLD was 16.1%. Participants in the highest quintile of DASH score showed strong inverse associations with risks of MAFLD (OR = 0.85; 95% CI, 0.80-0.91; P(trend) < 0.001) compared with participants in the lowest quintile. The association between DASH and nonobese MAFLD (OR = 0.69; 95% CI, 0.61-0.78; P(trend) < 0.001) was stronger (I(2) = 78.5 % ; P(heterogeneity) = 0.001) than that with obese MAFLD (OR = 0.90; 95% CI, 0.83-0.98; P(trend) = 0.002). There was a null association between AMED and MAFLD risk. CONCLUSIONS: In LEMRs, a DASH diet but not AMED was associated with MAFLD. The relationship appeared to be more pronounced in nonobese MAFLD individuals than in obese MAFLD individuals. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-021-12486-x.