In 631 treatment-naïve MASLD patients (mean age 41.5, 72% male) followed for 96 weeks of lifestyle intervention, MRI-measured changes in four abdominal fat depots were compared for predicting relapse. Only the 48-week relative decrease in peripancreatic mesenteric fat thickness (MFT1) mattered: each 10% reduction lowered odds of losing MRI-PDFF response (OR 0.48, 95% CI 0.34-0.69) and liver stiffness response (OR 0.53, 95% CI 0.28-0.99). Periumbilical mesenteric, preperitoneal and perirenal fat showed no independent association. AUCs were 0.70 for steatosis and 0.77 for stiffness relapse.
The finding fits a growing view that visceral fat is not one tissue. Depots draining into the portal circulation, like mesenteric fat near the pancreas, plausibly deliver free fatty acids and inflammatory cytokines straight to the liver, which could explain why this depot tracks hepatic durability better than body weight alone. The practical message is encouraging but indirect: weight loss that reaches deep visceral fat appears to protect gains from sliding backward, whereas initial liver improvement can prove fragile. Caveats are substantial. This is an observational, single-centre cohort, so MFT1 may be a marker of adherence or overall metabolic improvement rather than a causal driver. Measuring it requires MRI, so patients cannot track it at home, and an AUC of 0.70 is only modest discrimination. No external validation is reported. Editorially, this is incremental and hypothesis-generating: it supports sustained lifestyle change in MASLD and flags a mechanistic target, but it does not yet justify new clinical monitoring.