Association between phytochemical index and metabolic syndrome

BACKGROUND/OBJECTIVES: Although previous experimental studies reported the health benefits of foods rich in phytochemicals, few epidemiologic studies have investigated the associations between phytochemicals and metabolic disorders. This study aimed to calculate a phytochemical index (PI) and examine its association with metabolic syndrome in the Korean population. SUBJECTS/METHODS: Data of Korean adults aged ≥ 19 years who participated in the 2008–2016 Korea National Health and Nutrition Examination Surveys were analyzed. The PI was calculated using 24-hour intake recall data regarding whole grains, vegetables, fruits, legumes, nuts and seeds, and soybeans and soy products. Demographic and lifestyle data were obtained using self-administered questionnaires. A multivariable logistic regression was performed to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the prevalence of metabolic syndrome and its components according to PI quintiles. RESULTS: Overall, 31,319 adults were evaluated. Compared with men, women had a higher median PI level (9.96 vs. 13.63) and significantly higher caloric intake levels from most PI components (P < 0.05), except for soy products. After adjusting for multiple confounding variables, participants in the highest PI quintile had significantly lower prevalences of abdominal obesity (OR: 0.90, 95% CI: 0.81–0.99), hyperglycemia (OR: 0.83, 95% CI: 0.74–0.94), high blood pressure (OR: 0.82, 95% CI: 0.73–0.93), hypertriglyceridemia (OR: 0.84, 95% CI: 0.75–0.94), and metabolic syndrome (OR: 0.78, 95% CI: 0.69–0.88). CONCLUSIONS: Higher intakes of phytochemical-rich foods are associated with a lower prevalence of metabolic dysregulation and consequently, cardiometabolic diseases.