Dietary polyphenols are inversely associated with metabolic syndrome in Polish adults of the HAPIEE study

Purpose: The aim of this study was to evaluate the association between total and individual classes and subclasses of dietary polyphenol intake and prevalence of metabolic syndrome (MetS) in the Polish arm of the Health, Alcohol and Psychosocial factors In Eastern Europe cohort study. Methods: A cross-sectional population-based survey including 8821 adults (51.4 % female) was conducted in Kraków, Poland. Dietary polyphenol intake was evaluated using food frequency questionnaires and matching food consumption data with the Phenol-Explorer database. MetS was defined according to the International Diabetes Federation definition. Linear and logistic regression models were performed to estimate odds ratios (ORs) and confidence intervals (CIs). Results: Significant differences in age and energy intake among different categories of total dietary polyphenol intake were found. Body mass index (BMI), waist circumference (WC), blood pressure, and triglycerides were significantly lower among individuals in the higher quartiles of polyphenol intake, but a linear association was found only for BMI and WC. After adjusting for potential confounding factors, individuals in the highest quartile of polyphenol intake were less likely to have MetS (OR 0.80; 95 % CI 0.64, 0.98 and OR 0.70; 95 % CI 0.56, 0.86 for both men and women, respectively). High total polyphenol intake was negatively associated with WC, blood pressure, high lipoprotein cholesterol, and triglycerides in women, and fasting plasma glucose in both genders. Among individual classes of polyphenols, phenolic acids and stilbenes were significantly associated with MetS; lignans and stilbenes with WC; phenolic acids with blood pressure and triglycerides; and flavonoids with fasting plasma glucose. Among specific subclasses of polyphenols, hydroxycinnamic acids, flavanols, and dihydrochalcones had the most relevant role. Conclusions: Total and individual classes and subclasses of dietary polyphenols were inversely associated with MetS and some of its components.