Moderate dietary intake of omega-3 polyunsaturated fatty acids is associated with reduced all-cause mortality in metabolic dysfunction-associated steatotic liver disease.

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) can ameliorate multiple pathological alterations in metabolic dysfunction-associated steatotic liver disease (MASLD). However, their associations with mortality and optimal intake in MASLD remain unclear. We hypothesized that moderate dietary intake of n-3 PUFAs is associated with reduced all-cause mortality in MASLD. This study included 6367 individuals with MASLD from the National Health and Nutrition Examination Survey 1999-2018 to investigate these associations and determine the optimal intake. N-3 PUFAs intake was assessed using 24-hour dietary recalls. The association between n-3 PUFAs and mortality was evaluated using multivariable Cox regression and restricted cubic spline (RCS). The threshold effect was identified using piecewise regression with likelihood ratio tests. Cox regression indicated that a moderate dietary intake of n-3 PUFAs was significantly associated with reduced all-cause mortality in patients with MASLD. RCS analysis revealed a nonlinear, L-shaped relationship between them (Poverall < .0001; Pnonlinear = .0006), with an inflection point at 2.14 g/day. This value may be the optimal intake of n-3 PUFAs. Overall, moderate intake of n-3 PUFAs is associated with improved long-term survival in patients with MASLD, with an optimal intake of approximately 2.14 g/day.