Association between phytochemical index and metabolic syndrome

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.

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.

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).

Higher intakes of phytochemical-rich foods are associated with a lower prevalence of metabolic dysregulation and consequently, cardiometabolic diseases.