ABSTRACT Background and Aims Utilizing data from the 2017–2020 National Health and Nutrition Examination Survey (NHANES), this study examined the dose–response relationships and potential synergistic effects of physical activity (PA) and dietary quality (DQ) on the risk of metabolic dysfunction‐associated fatty liver disease (MAFLD) among US adults. Methods A nationally representative sample of 6511 participants was analyzed. PA was quantified as weekly recreational physical activity time, and DQ was assessed using the Healthy Eating Index–2015. Weighted multivariable logistic regression models, adjusted for sociodemographic, metabolic, and behavioral confounders, were used to evaluate associations. Dose–response patterns were examined using smooth curve fitting and segmented regression. Results Both higher PA and DQ were independently associated with reduced MAFLD risk (DQ: OR = 0.984, 95% CI = 0.981–0.987; PA: OR = 0.974, 95% CI = 0.969–0.978; both p 50. Compared to low PA (≤ 2.5 h/week), moderate (2.5–6.677 h/week) and high PA (> 6.677 h/week) were associated with a 34.1% and 47.7% lower risk, respectively. Moderate and high DQ reduced risk by 15.2% and 38.0% versus low DQ. The combined high‐PA/high‐DQ group showed the greatest risk reduction (OR = 0.325, 95% CI: 0.278–0.381). In individuals with low DQ, increasing PA from low to high reduced risk by 35.2%–39.3%, whereas improving DQ at low PA levels yielded a more modest reduction (13.4%–29.8%). Conclusions PA and DQ were independently associated with a lower MAFLD risk, with PA exhibiting a threshold effect (optimal at ~400 min/week) and DQ demonstrating cumulative benefits at higher scores. Combining high PA and high DQ yields the strongest protective effect, underscoring the importance of integrated lifestyle interventions for MAFLD prevention.
Xu et al. (Mon,) studied this question.