Association between dietary flavonoids intake and metabolic dysfunction-associated steatotic liver disease especially in non-smokers: a cross-sectional study in US adults.

BACKGROUND

The association between dietary flavonoids and fatty liver disease is still controversial. This study investigated the link between dietary flavonoids intake and metabolic-associated fatty liver disease (MAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

The study utilized data from the National Health and Nutrition Examination Survey cycles of 2007-2010 and 2017-2018. The relationship between dietary flavonoids intake and the prevalence of MAFLD/MASLD was evaluated using multivariate logistic regression models. Subgroup and population attributable fraction were employed to investigate the prevalence of MAFLD/MASLD in different smoking status groups.

RESULTS

The study included 5,645 participants. The fully adjusted multivariate logistic regression model indicated no significant association between ln flavonoids and MAFLD/MASLD (p > 0.05). Restricted cubic spline analysis identified a nonlinear relationship between ln flavonoids and MAFLD/MASLD, with 4.747 and 4.409 as the turning points, respectively. Subgroup and population attributable fraction analyses revealed that the negative association between flavonoids and MAFLD/MASLD is particularly significant in non-smokers. Mediation analysis indicated that the low-grade inflammation played a crucial role in the association. The study's robustness was validated through sensitivity analyses.

CONCLUSIONS

Our study highlighted a U-shaped association between ln flavonoids and MAFLD/MASLD, influenced by low-grade inflammation. Encouraging a flavonoid-rich diet is crucial for managing MAFLD/MASLD in non-smokers.