Association between saturated and polyunsaturated fatty acid proportions in total fat intake and mortality risk: mediation by the neutrophil percentage-to-albumin ratio

This study provides the novel evidence that the proportional composition of dietary fatty acids within total fat intake-rather than their absolute intake levels-is a critical determinant of longevity. By demonstrating that replacing SFA with PUFA reduces mortality risk through NPAR-mediated inflammatory pathways, our findings inform the World Health Organization's 2023 guidelines on dietary fat modification. These results shift the paradigm from isolated nutrient restrictions to balanced fatty acid ratios, offering a novel mechanistic basis for public health strategies aimed at extending healthy lifespan.