This chapter summarizes recent findings on the role of dietary and nutritional factors in the prevention and management of metabolic dysfunction-associated steatotic liver disease (MASLD), focusing on evidence from observational studies, clinical trials, and experimental models. Cross-sectional and cohort studies demonstrated that a greater adherence to plant-based and Mediterranean dietary patterns is associated with reduced liver fat content and improved liver enzyme profiles. Traditional Japanese dietary patterns rich in soy, vegetables, fish, and miso soup were also inversely associated with the fatty liver index in longitudinal analyses. Dietary fiber, particularly fermentable types, such as partially hydrolyzed guar gum, plays a central role in metabolic regulation, gut microbiota modulation, and hepatic lipid metabolism. Its protective effects are mediated, in part, through obesity reduction and enhancement of the gut–liver axis. Probiotics, prebiotics, and synbiotics have shown promise in clinical trials to improve liver biochemistry and reduce hepatic fibrosis, although heterogeneity in study protocols remains a challenge. Vitamin E supplementation has demonstrated efficacy in reducing hepatic transaminases, steatosis, and fibrosis, especially in patients without diabetes with early-stage MASLD. Long-term, well-designed intervention studies are warranted to establish standardized dietary recommendations for MASLD.