Regulation of Physical Activity and Sedentary Behavior on the Preventive Effect of Serum 25(OH)D Levels on NAFLD

Background: Uncertainty exists regarding the effects of physical activity (PA) and sedentary behavior on the connection between serum 25‐hydroxyvitamin D (25(OH)D) levels and nonalcoholic fatty liver disease (NAFLD). This study aims to evaluate these variables’ potential consequences and offers fresh perspectives and prevention strategies for NAFLD. Methods: A total of 3765 participants were included in the NHANES database (2017‐2018). The Global Physical Activity Questionnaire assessed PA and sedentary time as sedentary behavior. The risk of NAFLD was considered by utilizing vibration‐controlled transient elastography measurements. Logistic regression and nonlinearity analyses were utilized to investigate the influence of PA and sedentary behavior on the connection between serum 25(OH)D levels and NAFLD. Results: Multivariate‐adjusted OR (95% CI) of the highest quartile (Q4) participants of serum 25(OH)D levels was 0.40 (0.28–0.58) for NAFLD compared to the lowest quartile (Q1) participants of serum 25(OH)D levels. Compared to the Q1 of serum 25(OH)D levels and non‐PA group (< 600 MET‐minutes/week) participants, the Q4 of serum 25(OH)D levels and low‐intensity PA group (600–7999 MET‐minutes/week) participants had a lower risk of NAFLD (OR = 0.38, 95% CI: 0.22–0.67), and the Q4 of serum 25(OH)D levels and high‐intensity PA group (≥ 8000 MET‐minutes/week) participants had the lowest risk of NAFLD (OR = 0.24, 95% CI: 0.13–0.43). Sedentary behavior (≥ 6 h/day) attenuated the enhancing effect of PA on the negative correlation between serum 25(OH)D and NAFLD. Conclusions: Increased PA and reduced sedentary time may further protect against NAFLD by acting on serum 25(OH)D in US adults.