A vegetarian diet improves hepatic steatosis in MASLD patients through weight loss: a randomized controlled trial in China

Objective: The therapeutic potential of vegetarian diets in metabolic dysfunction-associated steatotic liver disease (MASLD) remains understudied in Asian populations. This randomized controlled trial aimed to evaluate the effects of a culturally adapted 6-month lacto-ovo-vegetarian diet (LOV-D) on hepatic steatosis and cardiometabolic risk factors through weight loss. Methods: In this randomized trial, 220 Chinese adults with MASLD were assigned to LOV-D (n = 110) or an omnivore diet (n = 110) for 6 months. Both groups received dietitian-supervised meal plans. Primary outcomes included weight, body fat, and visceral fat area (VFA) changes via bioelectrical impedance. Secondary outcomes encompassed hepatic steatosis (controlled attenuation parameter [CAP], ultrasonography) and cardiometabolic markers. Results: Among 186 completers (84.5% retention; mean age 40.0, BMI 28.4 kg m⁻²), the LOV-D group achieved greater reductions in weight (−1.40 kg [95% CI: −2.72 to −0.73], p = 0.033), fat mass (−11.94% vs −8.27%, p = 0.048), and VFA (−9.76% vs. −4.65%, p = 0.012) versus controls. LOV-D participants exhibited higher rates of composite endpoints (≥5% weight loss plus steatosis improvement): 33.3% vs. 16.1% by ultrasonography (p = 0.007) and 37.6% vs. 21.5% by CAP (p = 0.016). Significant improvements in Framingham risk scores, LDL cholesterol, and blood pressure occurred exclusively in the LOV-D group (all p < 0.05). Subgroup analyses revealed amplified benefits in females. Conclusions: A 6-month LOV-D intervention significantly attenuated MASLD severity through concurrent weight and visceral fat reduction, particularly in females. These findings support LOV-D as a culturally tailored, sex-responsive dietary strategy for MASLD management in Chinese populations.