Adolescents' dietary polyphenol intake in relation to serum total antioxidant capacity: the HELENA study.

We evaluated the association between intake of total polyphenols, polyphenol classes and the 10 most consumed individual polyphenols with serum total antioxidant capacity (TAC) in 749 European adolescents (53% girls; 15% overweight; 12.5-17.5 years-old) from the cross-sectional HELENA study of 2006-2007. Dietary polyphenol intake was calculated from two non-consecutive 24-h recalls matched with the Phenol-Explorer database. Multilevel linear models examined the associations between dietary polyphenols and TAC. Polyphenol intake was rather low (median = 321mg/day; p25 = 158; p75 = 536) and TAC was comparable to other literature findings (median = 1.57 mmol/L; p25 = 1.45; p75 = 1.74). Total polyphenol intake, polyphenol classes and the top 10 compounds were not associated with TAC in a linear, quadratic or cubic way in partially or fully confounder-adjusted models. A direct anti-oxidative effect of dietary polyphenol intake was not observed in European adolescents. Polyphenol biomarkers and additional antioxidant measures are needed in future prospective studies to confirm these results.

Total Polyphenol Intake Is Inversely Associated with a Pro/Anti-Inflammatory Biomarker Ratio in European Adolescents of the HELENA Study.

BACKGROUND: Although high dietary polyphenol intake is negatively associated with risk of certain inflammation-associated chronic diseases, the underlying mechanisms are not fully understood and few studies have explored this in adolescents. OBJECTIVE: This study aimed to evaluate the association between intakes of total polyphenols, polyphenol classes, and the 10 most commonly consumed individual polyphenols with inflammatory biomarkers in the blood of European adolescents. METHODS: In the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study, 526 adolescents (54% girls; 12.5-17.5 y) had data on inflammatory biomarkers and polyphenol intake from 2 nonconsecutive 24-h recalls via matching with the Phenol-Explorer database. Inflammatory biomarkers in serum were IL-1, IL-2, IL-4, IL-5, IL-6, IL-10, transforming growth factor ß1 (TGF-ß1), TNF-α, IFN-γ, soluble vascular adhesion molecule 1 (sVCAM-1), soluble intercellular adhesion molecule 1 (sICAM-1), soluble E-selectin (sE-selectin), white blood cells, lymphocytes, T cells, and C-reactive protein. Multilevel linear models were used to test associations of polyphenol intake with a pro/anti-inflammatory biomarker ratio [(zTNF-α + zIL-6 + zIL-1)/3/zIL-10] as well as with separate inflammatory biomarkers, adjusted for sociodemographic variables, diet inflammation index, BMI z score, and serum triglycerides. RESULTS: The pro/anti-inflammatory biomarker ratio was linearly inversely associated with the intake of total polyphenols (ß = -0.11, P = 0.040). When other inflammation biomarkers were considered, the serum IL-10 concentration was inversely associated with total polyphenol (ß = -0.12, P = 0.017) and flavonoid (ß = -0.12, P = 0.013) intakes, findings that were inconsistent with the biomarker ratio results. However, the anti-inflammatory capacity of polyphenols was confirmed by positive associations of IL-4 with phenolic acid (ß = 0.09 P = 0.049) and stilbene (ß = 0.13, P = 0.019) intakes and the negative association of IL-1, IL-2, and IFN-γ with lignan intake (ß = -0.10, P = 0.034; ß = -0.09, P = 0.049; ß = -0.11, P = 0.023). CONCLUSIONS: The negative relation with the overall pro/anti-inflammatory biomarker ratio suggests a potential anti-inflammatory role of high polyphenol intakes among European adolescents. Nevertheless, associations are dependent on polyphenol type and the inflammatory biomarker measured.

Lifestyle patterns and endocrine, metabolic, and immunological biomarkers in European adolescents: The HELENA study.

OBJECTIVE: To evaluate the association of lifestyle patterns related to physical activity (PA), sedentariness, and sleep with endocrine, metabolic, and immunological health biomarkers in European adolescents. METHODS: The present cross-sectional study comprised 3528 adolescents (1845 girls) (12.5-17.5 years) enrolled in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Cluster analysis was performed by including body composition, PA by accelerometry, self-reported sedentary behaviors, and sleep duration. We also measured endocrine, metabolic, and immunological biomarkers. RESULTS: Three-cluster solutions were identified: (a) light-PA time, moderate-vigorous-PA time and sedentary time, (b) light-PA time, moderate-vigorous-PA time, sedentary time and sleep time, (c) light-PA time, moderate-vigorous-PA time, sedentary time and body composition. In addition, each cluster solution was defined as: "healthy," "medium healthy," and "unhealthy" according to the presented rating. Analysis of variance showed that overall the healthiest groups from the three clusters analyzed presented a better metabolic profile. A decision tree analysis showed that leptin had a strong association with cluster 3 in both boys and girls, high-density lipoprotein cholesterol had the strongest association with clusters 1 and 3 in boys. Cortisol had the strongest association with cluster 1. HOMA index (homeostatic model assessment) and C3 showed a strong association with cluster 3 in girls. CONCLUSIONS: Our results support the existence of different interactions between metabolic health and lifestyle patterns related to PA, sedentariness, and sleep, with some gender-specific findings. These results highlight the importance to consider multiple lifestyle-related health factors in the assessment of adolescents' health to plan favorable strategies.

Dietary sources and sociodemographic and lifestyle factors affecting vitamin D and calcium intakes in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study.

OBJECTIVE: To investigate dietary sources of Ca and vitamin D (VitD) intakes, and the associated sociodemographic and lifestyle factors, among European adolescents. DESIGN: Linear regression mixed models were used to examine sex-specific associations of Ca and VitD intakes with parental education, family affluence (FAS), physical activity and television (TV) watching while controlling for age, Tanner stage, energy intake and diet quality. SETTING: The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA)Cross-Sectional Study. SUBJECTS: Adolescents aged 12·5-17·5 years (n 1804). RESULTS: Milk and cheese were the main sources of Ca (23 and 19 % contribution to overall Ca intake, respectively). Fish products were the main VitD source (30 % contribution to overall VitD intake). Ca intake was positively associated with maternal education (ß=56·41; 95 % CI 1·98, 110·82) and negatively associated with TV viewing in boys (ß=-0·43; 95 % CI -0·79, -0·07); however, the significance of these associations disappeared when adjusting for diet quality. In girls, Ca intake was positively associated with mother's (ß=73·08; 95 % CI 34·41, 111·74) and father's education (ß=43·29; 95 % CI 5·44, 81·14) and FAS (ß=37·45; 95 % CI 2·25, 72·65). This association between Ca intake and mother's education remained significant after further adjustment for diet quality (ß=41·66; 95 % CI 0·94, 82·38). Girls with high-educated mothers had higher Ca intake. CONCLUSIONS: Low-educated families with poor diet quality may be targeted when strategizing health promotion programmes to enhance dietary Ca.

Risk factors for ischaemic heart disease in a Cretan rural population: a twelve year follow-up study.

BACKGROUND: Crete has been of great epidemiological interest ever since the publication of the Seven Countries Study. In 1988 a well-defined area of rural Crete was studied, with only scarce signs of coronary heart disease (CHD) despite the unfavorable risk profile. The same population was re-examined twelve years later aiming to describe the trends of CHD risk factors over time and discuss some key points on the natural course of coronary heart disease in a rural population of Crete. METHODS AND RESULTS: We re-examined 200 subjects (80.7% of those still living in the area, 62.4 +/- 17.0 years old). The prevalence of risk factors for CHD was high with 65.9% of men and 65.1% of women being hypertensive, 14.3% of men and 16.5% of women being diabetic, 44% of men being active smokers and more than 40% of both sexes having hyperlipidaemia. Accordingly, 77.5% of the population had a calculated Framingham Risk Score (FRS) > or = 15%, significantly higher compared to baseline (p < 0.001). The overall occurrence rate for CHD events was calculated at 7.1 per 1000 person-years (95% confidence interval: 6.8-7.3). CONCLUSION: The study confirms the unfavorable risk factor profile of a well defined rural population in Crete. Its actual effect on the observed incidence of coronary events in Cretans remains yet to be defined.

Inflammation and insulin resistance according to body composition in European adolescents: the HELENA study.

INTRODUCTION: Inflammation is related to insulin resistance in adults, especially on those individuals with high levels of body composition. OBJECTIVES: The aim of this study is to assess the relationship between a set of inflammatory biomarkers and insulin resistance by levels of body composition in a sample of European adolescents. MATERIAL AND METHODS: Nine hundred and sixty-two adolescents (442 boys and 520 girls) from nine European countries met the inclusion criteria of having measurements for the homeostasis model assessment (HOMA) and a set of inflammation-related biomarkers: C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin (IL-6), complement factors C3 and C4 and selected cell adhesion molecules. Body mass index (BMI), fat mass index (FMI) and waist circumference (WC) were categorized using tertiles. To assess the associations stratifying by body composition indexes, ANOVA and linear regression models were performed. RESULTS: Mean biomarkers' concentrations differed across BMI, FMI and WC tertiles (p < 0.05) by sex. In both sexes, insulin, HOMA, CRP, C3 and C4 were significantly different between categories (p < 0.001), always showing the highest mean concentration in the upper category of BMI, FMI and WC. The most consistent finding was an association between insulin resistance and C3 concentrations (p < 0.05), in the adolescents in the highest tertile of BMI, FMI and WC, except in the case of FMI in girls. CONCLUSION: Inflammatory and glucose metabolism markers differed by tertiles of body composition, being usually higher in the highest tertile. C3 complement factor was associated with insulin resistance in adolescents, especially those with high total and abdominal adiposity.