Challenging Macronutrient Priorities for Metabolic Syndrome in Office Workers: New Evidence Favours Moderate Over High Protein Intake

Abstract

This letter challenges the prevailing recommendation of high-protein, low-glycemic index (GI) diets for managing metabolic syndrome in sedentary occupational populations. Drawing on recent evidence from a large multinational trial, we demonstrate that a moderate-protein, moderate-GI dietary pattern was significantly superior to a high-protein, low-GI pattern in achieving prediabetes remission at both one-year and three-year follow-ups, with the benefits being independent of weight loss. Mechanistically, chronic high intake of branched-chain amino acids may activate mTOR signaling pathways that paradoxically promote insulin resistance over extended periods. For sedentary office workers—who exhibit reduced postprandial fat oxidation and blunted muscle glucose uptake—moderate-protein, fiber-rich dietary patterns emphasizing whole grains and plant-forward protein sources offer superior sustainability, adherence, and metabolic outcomes compared to high-protein approaches. We urge occupational health guidelines to revise their endorsement of high-protein diets and instead priorities moderate-protein, moderate-GI patterns aligned with general dietary guidelines, supported by implementation data from successful workplace canteen trials.