ABSTRACT
BACKGROUND AND AIM: Clinical data on the prevalence of metabolic-associated fatty liver disease (MAFLD) in obese and non-obese individuals within a diverse US population is scarce. Furthermore, the influence of physical activity (PA) and dietary quality (DQ) on MAFLD risk remains unclear. This study aims to assess the prevalence and clinical features of MAFLD and examine the relationship between PA and DQ with the risk of developing MAFLD. METHODS AND RESULTS: A cross-sectional analysis of data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) was conducted. The overall MAFLD prevalence was 41.9%, with 28.6% of participants being obese and 13.4% non-obese. Among those with MAFLD, 67.1% (95% confidence interval (CI): 59.1%-75.1%) were obese, and 32.9% (95% CI: 29.1%-36.7%) were non-obese. Non-obese MAFLD was more frequent in Asians (27.2%), while obese MAFLD was more prevalent in Blacks (66.3%). Metabolic comorbidities were more common in individuals with obese MAFLD, who also exhibited more advanced fibrosis. A high-quality diet (HQD) and increased PA were linked to reduced odds of both obese and non-obese MAFLD (odds ratio (OR) and 95% CI: 0.67 [0.51-0.88] and 0.57 [0.47-0.69]; 0.62 [0.43-0.90] and 0.63 [0.46-0.87], respectively). PA and HQD significantly decreased the risk of obese and non-obese MAFLD (OR and 95% CI: 0.46 [0.33-0.64] and 0.42 [0.31-0.57]). CONCLUSION: A substantial proportion of the US population is affected by both obese and non-obese MAFLD. A strong association exists between a lower risk of both types of MAFLD and adherence to an HQD and engagement in PA.