Association Between Revised Macronutrient Intake Ratios and Metabolic Syndrome

Background: The 2025 Dietary Reference Intakes for Koreans (KDRIs) revised the acceptable macronutrient distribution ranges (AMDRs), but evidence regarding their association with metabolic syndrome (MS) is limited. Methods: We analyzed data from 14,768 Korean adults aged ≥19 years who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) 2022–2024. Macronutrient intake ratios were classified according to the revised KDRIs. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) after adjustment for demographic, socioeconomic, lifestyle, and dietary factors. Isocaloric substitution analyses estimated the associations of replacing 5% of energy from carbohydrate with fat or protein while maintaining total energy intake. Results: Overall adherence to all three AMDRs was not significantly associated with prevalent MS. Carbohydrate intake > 65%E and fat intake < 15%E were associated with higher odds of prevalent MS, whereas fat intake > 30%E and protein intake > 20%E were associated with lower odds. Significant sex interactions were observed for carbohydrate and fat intake categories, while no significant age interactions were found for the categorical analyses. Theoretical isocaloric substitution of 5%E from carbohydrate with fat or protein was associated with lower odds of prevalent MS, with significant interaction by sex for fat substitution and by age group for both fat and protein substitutions. Conclusions: In this cross-sectional analysis, higher carbohydrate and lower fat intake were associated with higher odds of prevalent MS, whereas higher fat and protein intake and theoretical isocaloric substitution of carbohydrate with fat or protein were associated with lower odds.