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Background: Dietary misreporting is the main limitation of dietary assessments and has been associated with BMI during youth. However there are no prior studies assessing misreporting and cardiometabolic risks (CMRs) in adolescence., Objectives: To examine the associations between dietary misreporting and CMR factors in adolescents and to assess the potential bias in the association between CMR and energy intake (EI) driven by dietary misreporting., Methods: Two 24-hour dietary recalls were obtained from 1512 European adolescents (54.8% girls) aged 12.5-17.5 years. Physical activity was measured by accelerometry. Cut-offs suggested by Huang were applied to identify misreporters. Height, waist circumference (WC), the sum of 4 skinfold thicknesses, diastolic blood pressure (DBP), systolic blood pressure (SBP), and cardiorespiratory fitness (CRF) measurements were taken and serum triglycerides and total-/high-density lipoprotein cholesterol ratio were analyzed. A sex- and age-specific clustered CMR score (n = 364) was computed. Associations were investigated by multilevel regression analyses adjusting for age, sex, center, socioeconomic status, and physical activity., Results: Underreporting (24.8% adolescents) was significantly (P < 0.05) associated with a higher WC, waist-to-height ratio (WHeR), and sum of skinfold thickness, whereas overreporting (23.4% adolescents) was significantly associated with a lower WC, WHeR, sum of skinfold thickness, and SBP. Associations between CMR factors and EI were significantly affected by misreporting, considering various approaches. Significant, positive associations became inverse after adjusting for misreporting for WC and WHeR. The opposite was true for the sum of skinfold thickness, SBP, and CMR score. The associations between EI and DBP and CRF did not remain significant after adjusting for misreporting., Conclusions: CMR factors differed among misreporting groups, and both abdominal and total fat mass indicators were more strongly associated with all forms of misreporting than was BMI. Moreover, misreporting seems to bias EI and CMR associations in adolescents. Therefore, energy misreporting should be taken into account when examining diet-CMR associations., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Background: The present study aimed to examine the independent association between cardiorespiratory fitness, sedentary time and insulin resistance in European adolescents., Methods: A subset (N.=1097) of a large multicenter European study (HELENA-CSS study) was used in the present study. Serum concentrations of glucose (GF) and insulin (IF) were measured after overnight fast and homeostasis model assessment (HOMA-IR) was calculated. Sedentary time and time spent on moderate-to-vigorous physical activity (MVPA) was objectively measured by accelerometers. Moreover, sedentary activities were self-reported via questionnaires., Results: Multilevel linear regression analysis revealed that adolescents watching TV≥2 h/day had higher HOMA-IR (P=0.007). Further adjustment for MVPA, showed that watching TV≥2 h/day remained significantly associated with IR (P=0.002). In this model, MVPA was inversely associated with HOMA-IR (P=0.001). Further controlling for waist circumference showed that adolescents watching TV≥2 h/day continued to have higher HOMA-IR levels (P=0.002). Stratified analysis by weight status, revealed that watching TV≥2 h/day was independently associated with HOMA-IR only in normal weight adolescents, while MVPA was inversely associated with HOMA-IR in both overweight/obese and normal weight adolescents. Only the volume of maximum oxygen consumption (VO2max) over body fat mass ratio was inversely associated with HOMA-IR after controlling for several confounders., Conclusions: The present study showed that watching TV≥2 h/day and MVPA were associated with HOMA-IR. However, after controlling for several confounders, only VO2max/body fat mass ratio remained negatively associated with HOMA-IR. Future interventions should aim both to promote physical activity and reduce sedentary time in adolescents to improve their cardiorespiratory fitness and postpone the onset of diabetes in adulthood.

Objectives: Cardiovascular diseases (CVDs) are responsible of 31% of all deaths worldwide. Genetic predisposition to CVDs in adolescents remains largely unknown. Aims of present research are to examine the association of ADIPOQ gene polymorphisms with cardiovascular disease risk factors in European adolescents., Methods: A total of 14 polymorphisms in the ADIPOQ gene were genotyped in 1057 European adolescents (12-18 years old) from the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. We measured serum lipids and a CVD risk score, along with weight, height, triceps, and subscapular skinfold thickness, leptin, insulin and other markers of glucose regulation., Results: The rs822393, rs822395 and rs7649121 polymorphisms of ADIPOQ gene were significantly associated with several CVD risk factors [i.e. high-density lipoprotein cholesterol (HDL-C), apolipoprotein (Apo) A1, SBP and CVD risk score] in European adolescents. We also found an association of the TGAAGT ADIPOQ haplotype (rs822393, rs16861210, rs822395, rs822396, rs12495941 and rs7649121) with HDL-C and ApoA1 levels., Conclusion: Several individual polymorphisms (rs822393, rs822395 and rs7649121) and a haplotype of ADIPOQ gene were significantly associated with cardiovascular disease risk factors in European adolescents.

Aim: From a nutrigenetics perspective, we aim to investigate the moderating role of the Mediterranean diet and each of its subgroups in the association between C-reactive protein (CRP) gene polymorphisms and CRP blood concentration in adolescents., Methods: In 562 adolescents (13-17 y) of the European HELENA study, data was available on circulating CRP levels as inflammatory biomarker, three CRP gene SNPs (rs3093068, rs1204, rs1130864), food intake determined by a self-administered computerized 24 h-dietary recall for 2 days, and body composition. A 9-point Mediterranean diet score and each food subgroup were tested as moderator via SNP*diet interaction. Analyzes were adjusted for age, sex, puberty, adiposity and socioeconomic status., Results: The minor allele frequencies of rs3093068 and rs1130864 SNPs (GG and TT, respectively) were associated with higher CRP concentrations, while rs1205 (CT/TT) was associated with lower CRP concentrations. There were significant interactions between rs3093068 and Mediterranean diet (B = -0.1139, p = 0.011), or the fish food subgroup (B = -0.0090, p = 0.022), so that those with the highest genetic CRP risk underwent the highest CRP attenuation by a healthier diet. Although the effect of diet and SNP was substantial, the explained variance by interaction was only 1%., Conclusion: Greater adherence to the Mediterranean diet and particularly its fish component was associated with a lower CRP blood concentrations especially in those at highest genetic risk due to the rs3093068 SNP., (Copyright © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Objective : The aim of this study was to identify dietary patterns (DPs) in European adolescents and to examine the association between perceptions of healthy eating and the obtained DPs. Method: A multinational cross-sectional study was carried out in adolescents aged 12.5 to 17.5 years and 2,027 (44.9% males) were considered for analysis. A self-reported questionnaire with information on food choices and preferences, including perceptions of healthy eating, and two 24-hour dietary recalls were used. Principal component analysis was used to obtain sex-specific DPs, and linear analyses of covariance were used to compare DPs according to perceptions of healthy eating. Results: Three and four DPs for boys and girls were obtained. In boys and girls, there were significant associations between some perceptions about healthy food and the Breakfast-DP ( p  < 0.05). In boys, Breakfast-DP and Healthy Beverage-DP were associated with the perception of the own diet as healthy ( p  < 0.05). Healthy Beverage-DP was associated with those disliking fruits and vegetables ( p  < 0.05). Girls considering the own diet as healthy were associated with Mediterranean-DP, Breakfast-DP, and Unhealthy Beverage and Meat-DP ( p  < 0.05). The perception of snacking as a necessary part of a healthy diet was associated with Breakfast-DP in both genders ( p  < 0.05). Conclusions: In European adolescents, perceptions of healthy eating were mainly associated with a DP characterized by foods consumed at breakfast. Future studies should further explore these findings in order to implement health promotion programs to improve healthy eating habits in adolescents.

Purpose: To examine the adherence to the Mediterranean dietary pattern (MDP) in metabolically healthy overweight or obese (MHO) and metabolically unhealthy obese (MUO) European adolescents., Methods: In this cross-sectional study, 137 overweight/obese adolescents aged 12-17 years old from the HELENA study were included. Height, weight, waist circumference and skinfold thickness were measured and body mass index and body fat percent were calculated. Systolic and diastolic blood pressure, glucose, HDL cholesterol, triglycerides and cardiorespiratory fitness (20 m shuttle run test) were measured. MHO and MUO phenotypes were categorized following the Jolliffe and Janssen criteria. Two non-consecutive 24 h recalls were used for dietary intake assessment and the adherence to the MDP was calculated using the Mediterranean dietary pattern score (MDP score) (range 0-9)., Results: A total of 45 (22 girls) adolescents (32.8%) were categorized as MHO. The adherence to the MDP was significantly higher in MHO than in MUO adolescents regardless of age, sex, body fat percentage, energy intake and center (MDP score: 4.6 ± 1.6 vs. 3.9 ± 1.5, p = 0.036), but this difference became non-significant after further adjustment for cardiorespiratory fitness. Participants who had a low adherence to the MDP (MDP score ≤ 4) had a higher likelihood of having MUO phenotype regardless of sex, age, energy intake, center and body fat percentage (OR 2.2; 95% CI 1.01-4.81, p = 0.048)., Conclusions: Adherence to the MDP might be beneficial to maintain metabolic health in overweight/obese adolescents, yet cardiorespiratory fitness seems to play a key role on the metabolic phenotype.

Aim: To assess if a healthy diet might attenuate the positive sedentary-inflammation relation, whereas an unhealthy diet may increase the effect of sedentary behaviors on inflammatory biomarkers., Methods: In 618 adolescents (13-17 years) of the European HELENA study, data were available on body composition, a set of inflammation markers, and food intake assessed by a self-administered computerized 24 h dietary recall for 2 days. A 9-point Mediterranean diet score and an antioxidant-rich diet z-score were used as dietary indices and tested as moderators. A set of low-grade inflammatory characteristics was used as outcome: several cytokines in an inflammatory ratio (IL-6, IL-10, TNF-α, TGFβ-1), C-reactive protein, three cell-adhesion molecules (sVCAM-1, sICAM-1, sE-selectin), three cardiovascular risk markers (GGT, ALT, homocysteine) and three immune cell types (white blood cells, lymphocytes, CD3). Sedentary behaviors were self-reported and analyzed as total screen time. Multiple linear regression analyses tested moderation by diet in the sedentary behaviors-inflammation association adjusted for age, sex, country, adiposity (sum of six skinfolds), parental education, and socio-economic status., Results: Both diet scores, Mediterranean and antioxidant-rich diet, were significant protective moderators in the effect of sedentary behaviors on alanine-transaminase enzyme (P = 0.014; P = 0.027), and on the pro/anti-inflammatory cytokine ratio (P = 0.001; P = 0.004), but not on other inflammatory parameters., Conclusion: A higher adherence to the Mediterranean diet or an antioxidant-rich diet may attenuate the onset of oxidative stress signs associated by sedentary behaviors, whereas a poor diet seems to increase inflammation.

Objective: To analyse the Nutritional Knowledge Test (NKT) using Item Response Theory (ITR) analysis and to assess the construct validity of the Nutritional Knowledge Scale (NKTS) and its associations with adolescent food group consumption and nutritional biomarkers., Design: Cross-sectional study., Setting: Multicentre investigation conducted in ten European cities.ParticipantsAdolescents aged 12·5-17·5 years (n 3215) who completed over 75 % of the NKT., Results: Factor analysis indicated that the NKT can be analysed with a one-dimensional model. Eleven out of twenty-three items from the NKT presented adequate parameters and were selected to be included in the NKTS. Nutrition knowledge was positively associated with consumption of fruits, cereals, dairy products, pulses, meat and eggs, and fish, as well as with blood concentrations of vitamin C, β-carotene, n-3 fatty acids, holo-transcobalamin, cobalamin and folate; nutrition knowledge was negatively associated with intake of olives and avocado, alcohol and savoury snacks., Conclusions: The NKTS assessed nutritional knowledge adequately and it is proposed as a new tool to investigate this subject in future studies.

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., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background Adolescents having early puberty (EP) are more likely to have obesity and increased cardiometabolic and inflammatory markers and atherosclerosis risk. We aimed to assess the indirect and mediated effects of leptin and adiposity on the relation between EP and cardiometabolic and inflammatory markers in European adolescents. Methods A sample of 511 adolescents with EP (12.5-17.5 years) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study was studied. To assess whether leptin levels and adiposity mediate the relation between EP and several biomarkers, linear regression models for mediation analyses were performed. Results EP was positively associated with the atherogenic index (Ath-I) (β=0.174; 95%CI 0.029-0.265) and negatively associated with the C-reactive protein (CRP) (β=-0.284; 95%CI -0.542 to -0.028) in girls. These associations were fully mediated by leptin levels (9.5%) and adiposity (44%), respectively. Moreover, EP has indirect effects on the apolipoprotein A-1 (ApoA-1) levels through adiposity in girls (for body mass index [BMI], β=0.014; 95%CI 0.005-0.028, and for waist circumference [WC], β=0.011; 95%CI 0.003-0.024), and on ApoA-1 (β=0.012; 95%CI 0.004-0.025), apolipoprotein B (ApoB) (β=-0.004; 95%CI -0.011 to -0.0004) and CRP (β=-0.265; 95%CI -0.819 to -0.047) through abdominal fat in boys. Conclusions Leptin levels and adiposity seem to play an important indirect and mediation role in the association between EP and cardiometabolic and inflammatory markers in adolescents. Weight control should be recommended in order to control the impaired cardiometabolic and inflammatory status arising in early pubertal adolescents.

Objectives: To determine dietary patterns (DPs) and explain the highest variance of vitamin B 6 , folate, and B 12 intake and related concentrations among European adolescents., Methods: A total of 2173 adolescents who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence study met the eligibility criteria for the vitamin B intake analysis (46% boys) and 586 adolescents for the biomarkers analysis (47% boys). Two non-consecutive, 24-h, dietary recalls were used to assess the mean intakes. Concentrations were measured by chromatography and immunoassay testing. A reduced rank regression was applied to elucidate the combined effect of food intake of vitamin B and related concentrations., Results: The identified DPs (one per vitamin B intake and biomarker and by sex) explained a variability between 34.2% and 23.7% of the vitamin B intake and between 17.2% and 7% of the biomarkers. In the reduced rank regression models, fish, eggs, cheese, whole milk and buttermilk intakes were loaded positively for vitamin B intake in both sexes; however, soft drinks and chocolate were loaded negatively. For the biomarkers, a higher variability was observed in the patterns in terms of food loads such as alcoholic drinks, sugars, and soft drinks. Some food items were loaded differently between intakes and biomarkers such as fish products, which was loaded positively for intakes but negatively for plasma folate in girls., Conclusions: The identified DPs explained up to 34.2% and 17.2% of the variability of the vitamin B intake and plasma concentrations, respectively, in European adolescents. Further studies are needed to elucidate the factors that determine such patterns., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: To report dietary sugars consumption and their different types and food sources, in European adolescents., Methods: Food consumption data of selected groups were obtained from 1630 adolescents (45.6% males, 12.5-17.5 years) from the HELENA study using two nonconsecutive 24-h recalls. Energy intake, total sugars and free sugars were assessed using the HELENA-DIAT software. Multiple regression analyses were performed adjusting for relevant confounders., Results: Total sugars intake (137.5 g/day) represented 23.6% and free sugars (110.1 g/day), 19% of energy intake. Girls had significantly lower intakes of energy, carbohydrates, total sugars and free sugars. 94% of adolescents had a consumption of free sugars above 10% of total energy intake. The main food contributor to free sugars was 'carbonated, soft and isotonic drinks,' followed by 'non-chocolate confectionary' and 'sugar, honey, jam and syrup.' Older boys and girls had significantly higher intakes of free sugars from 'cakes, pies and biscuits.' Free sugars intake was negatively associated with low socioeconomic status for 'non-chocolate confectionary' and 'sugar, honey and jam' groups; with low maternal educational level for carbonated and 'soft drinks,' 'sugar, honey and jam,' 'cakes and pies' and 'breakfast cereals' groups; and with high paternal educational level for 'carbonated and soft drinks' and 'chocolates' group., Conclusions: The majority (94%) of studied adolescents consumed free sugars above 10% of daily energy intake. Our data indicate a broad variety in foods providing free sugars. Continued efforts are required at different levels to reduce the intake of free sugars, especially in families with a low educational level.

Background and Aims: The ideal cardiovascular health (iCVH) construct consists of 4 health behaviors (smoking status, body mass index, physical activity and diet) and 3 health factors (total cholesterol, blood pressure and fasting glucose). A greater number of iCVH components in adolescence are related to better cardiovascular health, but little is known about the correlates of iCVH in adolescents. Thus, the aim of the study was to examine correlates of iCVH in European adolescents., Methods and Results: The study comprised 637 European adolescents with complete iCVH data. Participants were part of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study, a cross-sectional, multicenter study conducted in 9 different European countries. Correlates investigated were sex and age, family affluence scale, maternal education, geographic location, sleep time, television viewing, duration of pregnancy, birth weight and breastfeeding. Younger adolescents, those whose mothers had medium/high education or those who watched television less than 2 h per day had a greater number of iCVH components compared to those who were older, had a mother with low education or watched television 2 h or more daily (P ≤ 0.01)., Conclusion: Since in our study older adolescents had worse iCVH than younger adolescents, early promotion of cardiovascular health may be important. Future studies may also investigate the usefulness of limiting television viewing to promote iCVH. Finally, since adolescents of mothers with low education had poorer iCVH, it may be of special interest to tailor public health promotion to adolescents from families with low socioeconomic status., (Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Background and Aims: Inflammation may influence the cardio-metabolic profile which relates with the risk of chronic diseases. This study aimed to assess the inflammatory status by metabolic health (MH)/body mass index (BMI) category and to assess how inflammatory markers can predict the cardio-metabolic profile in European adolescents, considering BMI., Methods and Results: A total of 659 adolescents (295 boys) from a cross-sectional European study were included. Adolescents were classified by metabolic health based on age- and sex-specific cut-off points for glucose, blood pressure, triglycerides, high density cholesterol and BMI. C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin (IL-6), complement factors (C3, C4) and cell adhesion molecules were assessed., Results: Metabolically abnormal (MA) adolescents had higher values of C3 (p < 0.001) and C4 (p = 0.032) compared to those metabolically healthy (MHy). C3 concentrations significantly increased with the deterioration of the metabolic health and BMI (p < 0.001). Adolescents with higher values of CRP had higher probability of being in the overweight/obese-MH group than those allocated in other categories. Finally, high C3 and C4 concentrations increased the probability of having an unfavorable metabolic/BMI status., Conclusions: Metabolic/BMI status and inflammatory biomarkers are associated, being the CRP, C3 and C4 the most related inflammatory markers with this condition. C3 and C4 were associated with the cardio-metabolic health consistently., (Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

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 (β=56·41; 95 % CI 1·98, 110·82) and negatively associated with TV viewing in boys (β=-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 (β=73·08; 95 % CI 34·41, 111·74) and father's education (β=43·29; 95 % CI 5·44, 81·14) and FAS (β=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 (β=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.

Objectives: Adolescents in the European Union (EU) exhibit a higher prevalence of vitamin D (VitD) deficiency than other age groups. The degree to which sunlight exposure 25-hydroxyvitamin D [25(OH)D] concentrations depends on a variety of factors, including diet. Nevertheless, the relationship between calcium and VitD intake and 25(OH)D concentrations has not been previously studied among adolescents living in different EU countries and consequently in different latitudes. Therefore, the aim of this study was to examine whether calcium and VitD intakes are differentially associated with 25(OH)D in adolescents from northern, central and southern EU countries., Methods: The present analysis included 178 adolescents from northern EU countries, 251 from central EU countries, and 212 from southern EU countries (ages 12.5-17.5 y). Mixed model linear regression analyses stratified by geographic location were used to verify associations between calcium and VitD intake and 25(OH)D concentrations. Age, Tanner stage, seasonality, energy intake, and supplement use were entered as covariates., Results: Only the calcium intake of central EU adolescents was positively associated with 25(OH)D (α = 0.005; 95% confidence interval, 0.007-0.028)., Conclusions: Further longitudinal studies should confirm these observations, as this could be important for future public health interventions aiming to increase 25(OH)D concentrations in adolescents., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objectives: This study aimed to explore the associations of liver biomarkers with cardiometabolic risk factors and their clustering, and to provide reference values (percentiles) and cut-off points for liver biomarkers associated with high cardiometabolic risk in European adolescents., Methods: Alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), aspartate aminotransferase to ALT ratio (AST/ALT), waist circumference, blood pressure, triglycerides, high-density lipoprotein cholesterol and insulin were measured in 1084 adolescents. We computed a continuous cardiometabolic risk score and defined the high cardiometabolic risk., Results: Higher ALT and GGT and lower AST/ALT were associated with adiposity and with the number of adverse cardiometabolic risk factors (Ps < 0.05). Higher GGT and lower AST/ALT were associated with higher cardiometabolic risk score (Ps < 0.001) in males and females, and ALT only in males (Ps < 0.001). Gender- and age-specific percentiles for liver biomarkers were provided. Receiver operating characteristic analyses showed a significant discriminatory accuracy of AST/ALT in identifying the low/high cardiometabolic risk (Ps < 0.01) and thresholds were provided., Conclusions: Higher GGT and lower AST/ALT are associated with higher cardiometabolic risk factors and their clustering in male and female European adolescents, whereas the associations of ALT were gender dependent. Our results suggest the usefulness of AST/ALT as a screening test in the assessment of adolescents with high cardiometabolic risk and provide gender- and age-specific thresholds that might be of clinical interest., (© 2014 World Obesity.)

Objective: We studied in European adolescents (i) the association between cardiorespiratory fitness and ideal cardiovascular health as defined by the American Heart Association and (ii) whether there is a cardiorespiratory fitness threshold associated with a more favourable cardiovascular health profile., Methods: Participants included 510 (n=259 girls) adolescents from 9 European countries. The 20 m shuttle run test was used to estimate cardiorespiratory fitness. Ideal cardiovascular health was defined as meeting ideal levels of the following components: four behaviours (smoking, body mass index, physical activity and diet) and three factors (total cholesterol, blood pressure and glucose)., Results: Higher levels of cardiorespiratory fitness were associated with a higher number of ideal cardiovascular health components in both boys and girls (both p for trend ≤0.001). Levels of cardiorespiratory fitness were significantly higher in adolescents meeting at least four ideal components (13% higher in boys, p<0.001; 6% higher in girls, p=0.008). Receiver operating characteristic curve analyses showed a significant discriminating accuracy of cardiorespiratory fitness in identifying the presence of at least four ideal cardiovascular health components (43.8 mL/kg/min in boys and 34.6 mL/kg/min in girls, both p<0.001)., Conclusions: The results suggest a hypothetical cardiorespiratory fitness level associated with a healthier cardiovascular profile in adolescents. The fitness standards could be used in schools as part of surveillance and/or screening systems to identify youth with poor health behaviours who might benefit from intervention programmes., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background/objectives: The objectives of this study were to investigate the relationship between inflammatory parameters (CRP, c-reactive protein; AGP, α1-acid glycoprotein), iron status indicators (SF, serum ferritin; sTfR, soluble transferrin receptor) and body mass index (BMI) z-score, fat-free mass (FFM) and fat mass (FM) in European adolescents. Differences in intake for some nutrients (total iron, haem and non-haem iron, vitamin C, calcium, proteins) were assessed according to BMI categories, and the association of nutrient intakes with BMI z-score, FM and FFM was evaluated., Methods: A total of 876 adolescents participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence-Cross Sectional Study were included in the study sample., Results: Mean CRP values (standard error; s.e.) were significantly higher in overweight/obese adolescents (1.7±0.3 and 1.4±0.3 mg/l in boys and girls, respectively) than in thin/normal-weight adolescents (1.1±0.2 and 1.0±0.1 mg/l in boys and girls, respectively) (P<0.05). For boys, mean SF values (s.e.) were significantly higher in overweight/obese adolescents (46.9±2.7 μg/l) than in thin/normal-weight adolescents (35.7±1.7 μg/l) (P<0.001), whereas median sTfR values did not differ among BMI categories for both boys and girls. Multilevel regression analyses showed that BMI z-score and FM were significantly related to CRP and AGP (P<0.05). Dietary variables did not differ significantly among BMI categories, except for the intake of vegetable proteins, which, for boys, was higher in thin/normal-weight adolescents than in overweight/obese adolescents (P<0.05)., Conclusions: The adiposity of the European adolescents was sufficient to cause chronic inflammation but not sufficient to impair iron status and cause iron deficiency.

Unlabelled: Early menarche has been associated with adult overweight, cardiovascular risk factors, and other diseases. Little is known about the determinants of menarcheal age (MA). Therefore, the main aim of this study was to examine the associations between early life programming factors and menarcheal age in European adolescents. Secondly, the influence of sociodemographical factors on menarcheal age was also studied. A total of 1,069 European girls from the HELENA cross-sectional study, aged 12.5-17.5 years, were included in this study. Using multilevel linear regression models, a possible association between birth weight and length, ponderal index at birth, gestational age, duration of exclusive breastfeeding, and menarcheal age was examined. Associations between geographical gradient, number of siblings, physical activity (PA), dietary factors, and menarcheal age were also examined. After adjustment, menarcheal age was positively associated with birth weight and length (p = 0.01 and p = 0.01)., Conclusion: These findings confirm that birth weight and length may have a programming effect on menarcheal age. Next to this finding, sociodemographic factors were not associated with menarcheal age.

Background: Previous studies suggest that dietary protein might play a beneficial role in combating obesity and its related chronic diseases. Total, animal and plant protein intakes and their associations with anthropometry and serum biomarkers in European adolescents using one standardised methodology across European countries are not well documented., Objectives: To evaluate total, animal and plant protein intakes in European adolescents stratified by gender and age, and to investigate their associations with cardio-metabolic indicators (anthropometry and biomarkers)., Methods: The current analysis included 1804 randomly selected adolescents participating in the HELENA study (conducted in 2006-2007) aged 12.5-17.5 y (47% males) who completed two non-consecutive computerised 24-h dietary recalls. Associations between animal and plant protein intakes, and anthropometry and serum biomarkers were examined with General linear Model multivariate analysis., Results: Average total protein intake exceeded the recommendations of World Health Organization and European Food Safety Authority. Mean total protein intake was 96 g/d (59% derived from animal protein). Total, animal and plant protein intakes (g/d) were significantly lower in females than in males and total and plant protein intakes were lower in younger participants (12.5-14.9 y). Protein intake was significantly lower in underweight subjects and higher in obese ones; the direction of the relationship was reversed after adjustments for body weight (g/(kg.d)). The inverse association of plant protein intakes was stronger with BMI z-score and body fat percentage (BF%) compared to animal protein intakes. Additionally, BMI and BF% were positively associated with energy percentage of animal protein., Conclusions: This sample of European adolescents appeared to have adequate total protein intake. Our findings suggest that plant protein intakes may play a role in preventing obesity among European adolescents. Further longitudinal studies are needed to investigate the potential beneficial effects observed in this study in the prevention of obesity and related chronic diseases.

We examined the association of physical activity (PA), cardiovascular fitness (CVF) and fatness with total homocysteine (tHcy) concentrations in European adolescents. The present study comprised 713 European adolescents aged 14.8 ± 1.2 y (females 55.3%) from the multicenter HELENA cross-sectional study. PA was assessed through accelerometry, CVF by the 20-m shuttle run test, and body fat by skinfold thicknesses with the Slaughter equation. Plasma folate, cobalamin, and tHcy concentrations were measured. To examine the association of tHcy with PA, CVF, and fatness after controlling for a set of confounders including age, maturity, folate, cobalamin, creatinine, smoking, supplement use, and methylenetetrahydrofolate reductase 677 genotype (CC 47%, CT 43%, TT 10%), bivariate correlations followed by multiple regression models were performed. In the bivariate correlation analysis, tHcy concentrations were slightly negatively correlated (p<0.05) with CVF in females (measured both by stages: r=-0.118 and by VO2max: r=-0.102) and positively with body mass index (r=0.100). However, daily time spent with moderate and vigorous PA showed a weak positive association with tHcy in females (p<0.05). tHcy concentrations showed a tendency to decrease with increasing CVF and increase with increasing BMI in female European adolescents. However, tHcy concentrations were positively associated with moderate and vigorous PA in female European adolescents.

Objectives: Previous research showed that low concentration of biomarkers in the blood during adolescence (i.e., iron status; retinol; and vitamins B6, B12, C, and D) may be involved in the early stages of development of many chronic diseases, such as hypertension. The aim was to evaluate if iron biomarkers and vitamins in the blood are associated with blood pressure in European adolescents., Methods: Participants from the Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional study (N = 1089; 12.5-17.5 y; 580 girls) were selected by complex sampling. Multilevel linear regression models examined the associations between iron biomarkers and vitamins in the blood and blood pressure; the analyses were stratified by sex and adjusted for contextual and individual potential confounders., Results: A positive association was found in girls between RBC folate concentration and systolic blood pressure (SBP) (β = 3.19; 95% confidence interval [CI], 0.61-5.77), although no association between the vitamin serum biomarkers concentrations and diastolic blood pressure (DBP) was found. In boys, retinol was positively associated with DBP (β = 3.84; 95% CI, 0.51-7.17) and vitamin B6 was positively associated with SBP (β = 3.82; 95% CI, 1.46-6.18). In contrast, holotranscobalamin was inversely associated with SBP (β = -3.74; 95% CI, -7.28 to -0.21)., Conclusions: Levels of RBC folate and vitamin B6 in blood may affect BP in adolescents. In this context, programs aimed at avoiding high BP levels should promote healthy eating behavior by focusing on the promotion of vegetable proteins and foods rich in vitamin B12 (i.e., white meat and eggs), which may help to achieve BP blood control in adolescents., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background and Aims: Stress is hypothesized to facilitate the development of obesity, whose the foundations are already set during childhood and adolescence. We investigated the relationship between the stress-system, selected mechanisms of energy homeostasis and insulin resistance (IR) in a sample of European adolescents., Methods and Results: Within HELENA-CSS, 723 adolescents (12.5-17.5 years) from 10 European cities provided all the necessary data for this study. Fasting blood samples were collected for cortisol, leptin, insulin and glucose analysis. HOMA-IR was calculated from insulin and glucose concentrations. Adolescents' body fat (BF) %, age and duration of exclusive breastfeeding were assessed. For boys and girls separately, the relationship of cortisol with leptin, insulin, glucose and HOMA-IR was examined by computing Pearson correlation coefficients and Hierarchical Linear Models (HLMs), with 'city' as cluster unit, adjusting for age, BF% and duration of exclusive breastfeeding. In boys, Pearson correlation coefficients illustrated positive correlations of cortisol with insulin (r = 0.144; p = 0.013), glucose (r = 0.315; p < 0.001) and HOMA-IR (r = 0.180; p = 0.002), whilst in girls, this positive relationship was observed for leptin (r = 0.147; p = 0.002), insulin (r = 0.095; p = 0.050) and HOMA-IR (r = 0.099; p = 0.041), but not for glucose (r = 0.054; p = 0.265). Observed associations were independent of adolescents' age, BF% and duration of exclusive breastfeeding after computing HLMs., Conclusion: This study suggests that the stress-system is positively related to mechanisms of energy homeostasis and IR in European adolescents, and reveals a potential small gender difference in this relationship. The hypothesis that stress might facilitate the development of obesity during adolescence is supported., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Adolescence is a critical period, because major physical and psychologic changes occur during a very short period of time. Changes in dietary habits may induce different types of nutritional disorders and are likely to track into adulthood. The aim of this review is to describe the key findings related to nutritional status in European adolescents participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. We performed a cross-sectional study in 3528 (1845 females) adolescents aged 12.5–17.5 y. Birth weight was negatively associated with abdominal fat mass in adolescents and serum leptin concentrations (in female adolescents), providing additional evidence for a programming effect of birth weight on energy homeostasis control. Breakfast consumption was associated with lower body fat content and healthier cardiovascular profile. Adolescents eat half of the recommended amount of fruit and vegetables and less than two-thirds of the recommended amount of milk and milk products but consume more meat and meat products, fats, and sweets than recommended. For beverage consumption, sugar-sweetened beverages, sweetened milk, low-fat milk, and fruit juice provided the highest amount of energy. Although the intakes of saturated fatty acids (FAs) and salt were high, the intake of polyunsaturated FAs was low. Adolescents spent, on average, 9 h/d of their waking time (66–71% and 70–73% of the registered time in boys and girls, respectively) in sedentary activities. Factors associated with adolescents’ sedentary behavior included the following: 1) age; 2) media availability in the bedroom; 3) sleeping time; 4) breakfast consumption; and 5) season. Sedentary time was also associated with cardiovascular risk factors and bone mineral content. In European adolescents, deficient concentrations were identified for plasma folate (15%), vitamin D (15%), pyridoxal 5′-phosphate (5%), β-carotene (25%), and vitamin E (5%). Scientists and public health authorities should raise awareness of the importance of a healthy and sustainable lifestyle as a foundation of the health of the European population, now and in the future.

The purpose of this study was to identify the relevance of a set of risk factors for insulin resistance in adolescents from Europe and to consider their possible gender-specific associations. The Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) was conducted in 1053 European adolescents (mean age, 14.9 years) in a school setting in 9 countries. Three anthropometric markers of body fat and a dietary index were calculated. Total energy intake was estimated from a questionnaire. C-reactive protein, leptin, and vitamin D were assessed, and physical activity, cardiorespiratory fitness, and muscular strength were measured. Center, socioeconomic status, pubertal status, and season were used as potential confounders. The main outcome was the homeostasis model assessment used as a marker of insulin resistance. Correlations, analyses of covariance, and logistic regression models were used. In males, leptin was the only risk factor for insulin resistance after adjusting for confounders including markers of body fat (odds ratios (ORs) from 1.49 to 1.60). In females, leptin, vitamin D, and fitness were the remaining independent risk factors for insulin resistance after adjustments (OR 2.11; 95% confidential interval (CI) 1.29-3.45; OR 0.50, 95% CI 0.31-0.80; and OR 0.54, 95% CI 0.33-0.87, respectively). Our observations suggest a gender dimorphism in the identification of risk factors for high insulin resistance. Preventive strategies should focus on improving modifiable factors such as cardiorespiratory fitness and on ensuring vitamin D sufficiency. Randomized controlled trials focusing on these strategies are necessary to test their efficacy.

Objective: Coordinated European projects relying on standardized methods are needed to identify health inequalities across Europe. This study aimed to compare fitness, fatness, and cardiometabolic risk between urban adolescents from the south and center-north of Europe and to explore whether physical activity (PA) and other factors might explain these differences., Methods: The Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional project comprised 3528 adolescents from the south (4 cities) and central-north (6 cities) of Europe, 1089 of whom provided blood samples for analysis. Fitness (strength, speed-agility, and cardiorespiratory fitness), total and abdominal fatness (anthropometry and bioelectrical impedance), and cardiometabolic risk (z scores including fitness, fatness, blood lipids, insulin resistance, and blood pressure) were assessed. The analyses were adjusted for socioeconomic factors, objectively measured PA (accelerometry), total energy intake and diet quality, and genetic variants of the FTO rs9939609 polymorphism., Results: Adolescents from southern Europe were less fit and fatter according to all markers (P < .001). Differences in cardiometabolic risk scores were not consistent. Adolescents from the south were less active and this would largely explain the differences observed in speed-agility and cardiorespiratory fitness. Differences in total and abdominal fatness could not be explained by PA, energy intake, diet quality, or FTO rs9939609 polymorphism., Conclusions: Fitness and fatness levels indicate that urban adolescents from the south are less healthy than those from central-northern Europe. Our data suggest that differences in PA might explain differences in important health-related fitness components, yet factors explaining the differences in fatness encountered remain unknown.

Background/objectives: The objective of this study was to examine the relationship between amino acid (AA) intake and serum lipid profile in European adolescents from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study, and to assess whether this association was independent of total fat intake., Subjects/methods: Diet, skinfold thickness, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), TC/HDL-c ratio, low-density lipoprotein cholesterol (LDL-c), apolipoprotein B (Apo B), apolipoprotein A1 (Apo A1) and Apo B/Apo A1 ratio were measured in 454 12.5- to 17.5-year-old adolescents (44% boys). Intake was assessed via two non-consecutive 24-h dietary recalls. Data on maternal education and sedentary behaviors were obtained via questionnaires. Physical activity was objectively measured by accelerometry., Results: Alanine, arginine, asparaginic acid, glycine, histidine, lysine and serine intakes were inversely associated with serum TG concentrations in both boys and girls. Intake of other AA like alanine and/or arginine was also inversely associated with serum TC, LDL-c and Apo B/Apo A1 ratio only in girls. An inverse association was observed between intakes of alanine, isoleucine, leucine, methionine, serine, tryptophan, tyrosine and valine and TC/HDL-c ratio among female adolescents. Similar results were found in males for serine and tryptophan intakes. It is noteworthy, however, that associations were no longer significant in both genders when total fat intake was considered as a confounding factor., Conclusions: In this sample of adolescents, the association between AA intakes and serum lipid profile did not persist when dietary fat was considered. Therefore, dietary interventions and health promotion activities should focus on fat intake to improve lipid profile and potentially prevent cardiovascular disease.

Because socioeconomic factors (SEFs) may influence dietary quality and vitamin intakes, this study aimed to examine associations between socioeconomic factors and folate and vitamin B12 intakes as well as their related biomarkers in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. Vitamin intakes were obtained from two 24-hour recalls in 2253 participants (47% males). Vitamin B biomarkers were assessed in a subsample of 977 participants (46% males). Socioeconomic factors were assessed by questionnaire, and 1-way analysis of covariance and linear regression analysis were applied. For males and females, mean intakes of folate were 211.19 and 177.18 μg/d, and for vitamin B12, 5.98 and 4.54 μg/d, respectively. Levels of plasma folate, red blood cell folate, serum B12, and holotranscobalamin were 18.74, 807.19, 330.64, and 63.04 nmol/L in males, respectively, and 19.13, 770.16, 377.9, and 65.63 nmol/L in females, respectively. Lower folate intakes were associated with several SEFs, including maternal and paternal education in both sexes. Regarding folate biomarkers, lower plasma folate intakes were associated with single/shared care in males and with lower paternal occupation in females. Lower vitamin B12 intakes were associated with almost all the studied SEFs, except paternal occupation in both sexes. In females, when considering vitamin B12 biomarkers, lower plasma vitamin B12 was associated with lower maternal education and occupation, and lower holotranscobalamin was associated with lower maternal education and lower paternal occupation. In conclusion, from the set of socioeconomic determinants studied in a sample of European adolescents, maternal education and paternal occupation were more consistently associated with folate and vitamin B12 intakes and biomarkers concentrations., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: To test whether youths who engage in vigorous physical activity are more likely to have lean bodies while ingesting relatively large amounts of energy. For this purpose, we studied the associations of both physical activity and adiposity with energy intake in adolescents., Study Design: The study subjects were adolescents who participated in 1 of 2 cross-sectional studies, the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study (n = 1450; mean age, 14.6 years) or the European Youth Heart Study (EYHS; n = 321; mean age, 15.6 years). Physical activity was measured by accelerometry, and energy intake was measured by 24-hour recall. In the HELENA study, body composition was assessed by 2 or more of the following methods: skinfold thickness, bioelectrical impedance analysis, plus dual-energy X-ray absorptiometry or air-displacement plethysmography in a subsample. In the EYHS, body composition was assessed by skinfold thickness., Results: Fat mass was inversely associated with energy intake in both studies and using 4 different measurement methods (P ≤ .006). Overall, fat-free mass was positively associated with energy intake in both studies, yet the results were not consistent across measurement methods in the HELENA study. Vigorous physical activity in the HELENA study (P < .05) and moderate physical activity in the EYHS (P < .01) were positively associated with energy intake. Overall, results remained unchanged after adjustment for potential confounding factors, after mutual adjustment among the main exposures (physical activity and fat mass), and after the elimination of obese subjects, who might tend to underreport energy intake, from the analyses., Conclusion: Our data are consistent with the hypothesis that more physically active and leaner adolescents have higher energy intake than less active adolescents with larger amounts of fat mass., (Copyright © 2014 Mosby, Inc. All rights reserved.)

Background: High prevalence of vitamin D insufficiency (<75 nmol/l) has been previously reported in European adolescents. Vitamin D deficiency has been related to physical fitness and adiposity but it is not clearly known whether this relationship applies to growing children and adolescents., Aim: To determine how body composition and physical fitness are related to 25-hydroxyvitamin D [25(OH)D] concentrations in European adolescents., Design: The HEalthy Lifestyle in Europe by Nutrition in Adolescence-CSS study was a multi-centre cross-sectional study., Methods: Plasma 25(OH)D, body composition and physical fitness measures were obtained in 1006 European adolescents (470 males) aged 12.5-17.5 years. Stepwise regression and ANCOVA were performed by gender using 25(OH)D as dependent variable, with body composition, physical fitness as independent variables controlling for age, seasonality and latitude., Results: For males, maximum oxygen consumption (VO2max) (B = 0.189) and body mass index (BMI) (B = -0.124) were independently associated with 25(OH)D concentrations (both P < 0.05). For females, handgrip strength (B = 0.168; P < 0.01) was independently associated with 25(OH)D concentrations. Those adolescents at lower BMI and high fitness score presented significant higher 25(OH)D concentrations than those at lower fitness score in the other BMI groups (P < 0.05)., Conclusion: Cardiorespiratory fitness and upper limbs muscular strength are positively associated with 25(OH)D concentrations in male and female adolescents, respectively. Adiposity in males and low fat free mass in females are related to hypovitaminosis D. The interaction between fitness and BMI has a positive effect on 25(OH)D concentrations. Therapeutic interventions to correct the high rates of vitamin D deficiency in adolescents should consider physical fitness.

Dietary fatty acids (FA) play a role in several (patho)physiological processes at any age, and different FA have different effects on lipid status and health outcome. The present study aims to describe the FA intake and its main food sources in a population of healthy European adolescents and to assess the variation in intake as a function of non-dietary factors. FA intake was assessed with 24 h recall interviews in 1804 adolescents aged 12·5-17·5 years. Usual intakes were calculated using the multiple source method. Multilevel analyses, adjusting for study centre, were used to investigate the influence of non-dietary factors. The mean total fat intake was 33·3 (sd 1·2) % of total energy intake (%E). The mean SFA intake was 13·8 (sd 1·2) %E, with 99·8 % of the population exceeding the recommendations. SFA was mainly delivered by meat and cake, pies and biscuits. In most adolescents, the PUFA intake was too low, and 35·5 % of the population did not achieve the minimum recommended intake for α-linolenic acid (ALA). The main determinants of FA intake in the present study population were age and sex, as well as physical activity in the male subgroup. No contributions of body composition, socio-economic status or sexual maturation to the variance in FA intake were observed. In conclusion, the most important public health concerns regarding FA intake in this adolescent population were the low intake of ALA and the high intake of SFA, mainly seen in the younger-aged boys. In this group the major contributor to SFA was meat.

It is important to be able to evaluate vitamin status correctly at any age, but this is especially vital during adolescence since there are higher requirements for healthy growth and development. However, there are no currently available B-vitamin reference values for healthy adolescents. The aim of the present study is to assess the vitamin B status in European adolescents in order to contribute to the development of reference values for selected B-vitamins and total homocysteine (tHcy). Within the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) cross-sectional study, a sub sample of 1051 (499 males, 552 females) adolescents from ten European cities aged 12.5 to 17.49 were analyzed for fasting plasma folate (PF), red blood cell (RBC) folate, serum cobalamin (Cbl), holo-transcobalamin (Holo-TC), Vitamin B(6) (PLP), and tHcy. The level of significance was set at P < .05. Following the current cut-off for adults, 2% had low Cbl and 5% had low holo-TC concentrations. Low concentrations of both PF and RBC folate were identified in 10%. Five percent had PLP concentrations <20 nmol/L and 20% <30 nmol/L. Moreover, 5% had high tHcy; median values for the whole sample were: PF 16.0 nmol/L, RBC folate 721.9 nmol/L, Cbl 319 pmol/L, Holo-TC 57.8 pmol/L, and tHcy 6.7 μmol/L. Females had significantly higher median Cbl but lower PLP and tHcy concentrations (P < .01). THcy increased (P < .001) and PF (P < .001) concentrations decreased across age categories. Subjects showed significantly higher tHcy values at the fifth percentile of PF, corresponding with 7.5 nmol/L. Sex and age had an influence on most of the studied biomarkers and should be taken into account. The HELENA percentile distribution is consistent with data from smaller studies and could be used as reference value to characterize B-vitamin status of European adolescents., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The present study examined the associations of food behaviours and preferences with markers of insulin resistance and clustered metabolic risk factors score after controlling for potential confounders, including body fat in European adolescents. A cross-sectional study "Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study" of 3546 European adolescents aged 12.5-17.5 years was conducted, using a complete dataset on at least glucose, insulin and "Food Choice Questionnaire". Results indicated skipping breakfast, as well as the preference of some foods such as nuts, chocolate, burgers and pizzas, soft drinks or juices, explain part of homeostasis model assessment index variance. In addition, snacking regularly during school day is associated with higher metabolic risk score in females. In conclusion, the present findings suggest that intervention studies aimed to prevent insulin resistance and metabolic risk factors in youth should focus not only in influencing food and drink preferences, but also to ensure healthy food behaviour in adolescents. The harmful consequences in the choice of certain foods or drinks and food habits can be countered with proper planning and intervention programs to prevent insulin resistance and metabolic risk factors., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The aim of the study was to examine the association of muscular strength with markers of insulin resistance in European adolescents. The study comprised a total of 1,053 adolescents (499 males; 12.5-17.5 years) from ten European cities participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Cross-Sectional Study. Muscular strength was measured by the handgrip strength and standing long jump tests. Cardiorespiratory fitness was measured by the 20-m shuttle run test. Fasting insulin and glucose were measured and the homeostasis model assessment (HOMA) and quantitative insulin sensitivity check index (QUICKI) indices were calculated. Weight, height, waist circumference and skinfold thickness were measured, and body mass index (BMI) was calculated. In males, the handgrip strength and standing long jump tests were negatively associated with fasting insulin and HOMA (all P < 0.05) after controlling for pubertal status, country and BMI or waist circumference. When skinfold thickness was included in the model, the association became non-significant. In females, the standing long jump test was negatively associated with fasting insulin and HOMA (all P < 0.001) after controlling for pubertal status, country and surrogate markers of total or central body fat (BMI, waist circumference or skinfold thickness). Findings were retained in males, but not in females after controlling for cardiorespiratory fitness. The findings of the present study suggest that preventive strategies should focus not only on decreasing fatness and increasing cardiorespiratory fitness but also on enhancing muscular strength.

Background/objectives: To provide a detailed lipid profile of a European adolescent population considering age, gender, biological maturity, body mass index (BMI), fat mass (FM) and percentage body fat (BF)., Subjects/methods: Within Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA), a cross-sectional study was conducted to determine fasting serum concentrations of lipids, lipoproteins and apolipoproteins in 1076 adolescents aged 12.5-17.49 years from ten European centres., Results: All serum lipid concentrations were significantly higher in girls than in boys. In boys, age was negatively correlated with high-density lipoprotein (HDL)-cholesterol and total cholesterol (TC), and positively associated with triacylglycerides (TAG) (P < 0.01) whereas no significant associations were observed in girls. Biological maturity was negatively associated with TC, HDL-, low-density lipoprotein (LDL)- and non-HDL cholesterol in boys (all P<0.05) and negatively correlated with HDL-cholesterol in girls (P<0.05). BMI, FM and BF were significantly correlated with HDL-cholesterol, LDL-cholesterol, non-HDL cholesterol, apolipoprotein (apo) A1, apoB and TAG in both boys and girls., Conclusions: The lipid profile in adolescents is strongly determined by gender. Biological maturity, FM and percentage BF contribute to the variance in lipid concentrations and should be considered in future evaluations of lipid status.

Objective: To examine the association of physical activity and fitness with leptin concentrations in European adolescents, after taking into account several potential confounders including total body fat (TBF)., Study Design: We conducted a cross-sectional study in a school setting for the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. This study included 902 (509 girls) adolescents aged 12.5-17.5 years. Weight, height, and TBF (sum of 6 skinfold thickness) were measured, and fat free mass and body mass index were calculated. Physical activity was assessed by accelerometry. Physical fitness was assessed by the handgrip, standing long jump, 4 × 10-m shuttle run, and 20-m shuttle run tests. Serum fasting leptin, insulin, and glucose concentrations were measured, and homeostasis model assessment was computed. Multiple linear regression models were used., Results: Vigorous physical activity and fitness tests (all P < .05) were negatively associated with leptin, independently of several confounders including TBF and homeostasis model assessment. These associations remained significant after further controlling for each other (physical activity and fitness)., Conclusion: These results suggest that vigorous physical activity and fitness moderate the levels of leptin concentrations, regardless of relevant confounders including TBF. Intervention programs addressed to increase high intensity physical activity and fitness as well as to assess its impact on leptin concentration are required., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Objective: Since inadequate food consumption patterns during adolescence are not only linked with the occurrence of obesity in youth but also with the subsequent risk of developing diseases in adulthood, the establishment and maintenance of a healthy diet early in life is of great public health importance. Therefore, the aim of the present study was to describe and evaluate the food consumption of a well-characterized sample of European adolescents against food-based dietary guidelines for the first time., Design: The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study is a cross-sectional study, whose main objective was to obtain comparable data on a variety of nutritional and health-related parameters in adolescents aged 12·5-17·5 years., Setting: Ten cities in Europe., Subjects: The initial sample consisted of more than 3000 European adolescents. Among these, 1593 adolescents (54 % female) had sufficient and plausible dietary data on energy and food intakes from two 24 h recalls using the HELENA-DIAT software., Results: Food intake of adolescents in Europe is not optimal compared with the two food-based dietary guidelines, Optimized Mixed Diet and Food Guide Pyramid, examined in this study. Adolescents eat half of the recommended amount of fruit and vegetables and less than two-thirds of the recommended amount of milk (and milk products), but consume much more meat (and meat products), fats and sweets than recommended. However, median total energy intake may be estimated to be nearly in line with the recommendations., Conclusion: The results urge the need to improve the dietary habits of adolescents in order to maintain health in later life.

An adequate vitamin D status is essential during childhood and adolescence, for its important role in cell growth, skeletal structure and development. It also reduces the risk of conditions such as CVD, osteoporosis, diabetes mellitus, infections and autoimmune disease. As comparable data on the European level are lacking, assessment of vitamin D concentrations was included in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study. Fasting blood samples were obtained from a subsample of 1006 adolescents (470 males; 46·8 %) with an age range of 12·5-17·5 years, selected in the ten HELENA cities in the nine European countries participating in this cross-sectional study, and analysed for 25-hydroxycholecalciferol (25(OH)D) by ELISA using EDTA plasma. As specific reference values for adolescents are missing, percentile distribution were computed by age and sex. Median 25(OH)D levels for the whole population were 57·1 nmol/l (5th percentile 24·3 nmol/l, 95th percentile 99·05 nmol/l). Vitamin D status was classified into four groups according to international guidelines (sufficiency/optimal levels ≥ 75 nmol/l; insufficiency 50-75 nmol/l; deficiency 27·5-49·99 nmol/l and severe deficiency < 27·5 nmol/l). About 80 % of the sample had suboptimal levels (39 % had insufficient, 27 % deficient and 15 % severely deficient levels). Vitamin D concentrations increased with age (P < 0·01) and tended to decrease according to BMI. Geographical differences were also identified. Our study results indicate that vitamin D deficiency is a highly prevalent condition in European adolescents and should be a matter of concern for public health authorities.

Background/objectives: Our objective was to describe the fluid and energy consumption of beverages in a large sample of European adolescents., Subjects/methods: We used data from 2741 European adolescents residing in 8 countries participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS). We averaged two 24-h recalls, collected using the HELENA-dietary assessment tool. By gender and age subgroup (12.5-14.9 years and 15-17.5 years), we examined per capita and per consumer fluid (milliliters (ml)) and energy (kilojoules (kJ)) intake from beverages and percentage consuming 10 different beverage groups., Results: Mean beverage consumption was 1611 ml/day in boys and 1316 ml/day in girls. Energy intake from beverages was about 1966 kJ/day and 1289 kJ/day in European boys and girls, respectively, with sugar-sweetened beverages (SSBs) (carbonated and non-carbonated beverages, including soft drinks, fruit drinks and powders/concentrates) contributing to daily energy intake more than other groups of beverages. Boys and older adolescents consumed the most amount of per capita total energy from beverages. Among all age and gender subgroups, SSBs, sweetened milk (including chocolate milk and flavored yogurt drinks all with added sugar), low-fat milk and fruit juice provided the highest amount of per capita energy. Water was consumed by the largest percentage of adolescents followed by SSBs, fruit juice and sweetened milk. Among consumers, water provided the greatest fluid intake and sweetened milk accounted for the largest amount of energy intake followed by SSBs. Patterns of energy intake from each beverage varied between countries., Conclusions: European adolescents consume an average of 1455 ml/day of beverages, with the largest proportion of consumers and the largest fluid amount coming from water. Beverages provide 1609 kJ/day, of which 30.4%, 20.7% and 18.1% comes from SSBs, sweetened milk and fruit juice, respectively.

Objective: To examine the independent association of total and central body fat and cardiorespiratory fitness with markers of insulin resistance after controlling for several potential confounders in European adolescents participating in the HELENA-CSS (Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional) study., Methods: We conducted a cross sectional study (the HELENA-CSS) which comprised 1053 (12.5-17.5 years) adolescents from 10 European cities. Weight, height, waist circumference and skinfold thickness were measured, and body mass index (BMI) was calculated. Cardiorespiratory fitness was measured by the 20-m shuttle run test. Markers of insulin resistance were fasting insulin and glucose, and homeostasis model assessment (HOMA)., Results: HOMA and insulin were positively associated with BMI, skinfolds and waist circumference after controlling for center, age, pubertal status and cardiorespiratory fitness (all P ? 0.01). HOMA and insulin were negatively associated with cardiorespiratory fitness in adolescents with moderate to high levels of total and central body fat (all P ? 0.01)., Conclusions: HOMA and insulin were associated with total and central body fat in European adolescents. Moreover, cardiorespiratory fitness explained a part of the HOMA and insulin variance in those adolescents with moderate to high levels of total and central body fat, and also, to some extent, in those with low to middle fat mass.

Background: An adequate nutritional status of antioxidant vitamins (vitamins A, C, E) and b-carotene is essential especially during childhood and adolescence, because of their important roles in cell growth and development. Currently, there are no physiological reference values for blood concentration of these vitamins and b-carotene in apparently healthy European adolescents. The aim of the current study was to obtain reliable and comparable data of antioxidant vitamins and b-carotene in a cross-sectional study, within HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence), which was conducted in a representative sample of adolescents from ten European cities., Material and Methods: From a subsample of 1,054 adolescents (males= 501) of the HELENA Cross Sectional Study with an age range of 12.5 to 17.49 years, fasting blood samples were taken and analyzed for vitamins A, E, C, and b-carotene status. As specific reference values for adolescents are missing, percentile distribution by age and sex is given., Results: Mean concentrations were the following: Retinol: 356.4 ± 107.9 cm/mL; alpha-tocopherol: 9.9 ± 2.1 microg/mL; vitamin C: 10.3 ± 3.3 mg/L; and b-carotene: 245.6 ± 169.6 cm/mL. Females showed higher alpha-tocopherol and vitamin C values compared with males and 17-year-old boys had higher retinol levels than the same-aged girls (p = 0.018). Retinol serum concentrations increased significantly according to age in both gender, but girls had also significantly increasing b-carotene levels by age., Conclusions: For the first time, concentrations of antioxidant vitamins and pro-vitamin beta-carotene have been obtained in a representative sample of apparently healthy European adolescents. These data can contribute to the establishment of reference ranges in adolescents.

The aim of the current study was to compare the association of several anthropometric indices, with insulin resistance (IR) proxy measures in European adolescents. The present study comprises 1,097 adolescents aged 12.5-17.5 from ten European cities participating in the HELENA study. Weight, height, waist circumference (WC) and hip circumference, skinfolds thickness, fat mass (FM), fasting plasma glucose (G(F)) and serum insulin (I(F)) levels were measured. HOMA (as indicator of IR body mass index (BMI), waist to hip ratio (WHR) and waist to height ratio (WHtR) were calculated. I(F) and HOMA were statistically significantly related to BMI, WC, skinfold sum, WHtR, WHR and FM. BMI, WC, WHtR, skinfold sum and FM displayed similar correlation with I(F) and HOMA as opposed to WHR where lower correlation with IR indices was detected in the overall sample. Similar results were found for boys, girls and underweight/normal weight adolescents. On the other hand, WC and WHtR were found to be more strongly associated with IR proxy measures compared to the rest of anthropometric indices among overweight/obese subjects. Based on the current findings, WC and WHtR could be used, alternatively, to identify the overweight/obese adolescent at risk for developing IR. In addition, all aforementioned anthropometric indices, except WHR, could be used among the underweight/normal weight adolescents.

Currently, blood levels to define vitamin deficiency or optimal status in adolescents are extrapolated from adults. This may be not adequate as vitamin requirements during adolescence depend on the process of sexual maturation, rapid increasing height and weight, among other factors. In order to establish the state of the art, Medline database (www.ncvi.nlm.nih.gov) was searched for studies published in Europe between 1981 and 2010 related to liposoluble vitamin status in adolescents. A comparison of the vitamin status published in the reviewed articles was difficult due to the lack of studies, lack of consensus on cut-off levels indicating deficiency and optimal vitamin levels and the different age-ranges used. In spite of that, deficiency prevalence varied for vitamin D (13-72%), vitamin A (3%), E (25%) and β-carotene (14-19%). Additional factors were considered as possible determinants. We conclude that it is necessary to establish a consensus on acceptable ranges and cut-offs of these vitamins during adolescence. Representative data are still missing; therefore, there is a high need to get deeper into the investigation on liposoluble vitamins in this population group.

Objectives: The purpose of this study was to determine the sex-specific physical activity (PA) intensity thresholds that best discriminate between unhealthy/healthy cardiorespiratory fitness (CRF)., Methods: Participants included 1,808 adolescents (964 girls), aged 12.5-17.5 years, from the HELENA study. We measured PA by accelerometer and calculated the time spent at light, moderate, vigorous, and moderate-to-vigorous (MVPA) intensities. CRF was assessed by the 20-m shuttle-run test. Adolescents were dichotomized (unhealthy/healthy) based on sex- and age-specific FITNESSGRAM standards. Receiver operating characteristic (ROC) analysis was used to determine thresholds that best discriminate between CRF categories., Results: ROC analyses revealed that the PA thresholds that best discriminate between unhealthy/healthy CRF were ≥152, ≥33, ≥13, and ≥52 min/day in light, moderate, vigorous, and MVPA, respectively. In boys, the PA thresholds associated with a healthy CRF were ≥37, ≥19, and ≥56 min/day in moderate, vigorous, and MVPA, respectively, whereas in girls were ≥152, ≥34, ≥12, and ≥51 min/day in light, moderate, vigorous, and MVPA, respectively. Spending at least 60 min/day in MVPA was also associated with a healthy CRF (odds ratios: 1.75, 1.94, and 1.57, all P < 0.05, for the whole sample, boys, and girls, respectively)., Conclusions: This study shows sex- and intensity-specific PA thresholds to discriminate between adolescents with a healthy CRF from those with a less favorable or unhealthy CRF level., (© 2010 Wiley-Liss, Inc.)

Introduction: The influence of socioeconomic status on health-related fitness is not clear., Aim: To examine the influence of socioeconomic status on health-related fitness in adolescents., Methods: A total of 3,259 adolescents (15.0 +/- 1.3 y) from the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) participated in the study. Socioeconomic status was assessed by the family affluence scale (FAS). Speed-agility, muscular strength and cardiorespiratory fitness were assessed. Covariates included total body fat, physical activity and pubertal status., Results: Adolescents with high FAS had significantly higher fitness levels than their peers of lower FAS categories except for speed-agility and handgrip in boys. Overall, the associations observed presented a medium to large effect size., Conclusion: These results suggest that socioeconomic status is positively associated with physical fitness in European adolescents independently of total body fat and habitual physical activity.

Objective: To provide an overview of the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) design, with particular attention to its quality control procedures. Other important methodological aspects are described in detail throughout this supplement., Design: Description of the HELENA-CSS sampling and recruitment approaches, standardization and harmonization processes, data collection and analysis strategies and quality control activities., Results: The HELENA-CSS is a multi-centre collaborative study conducted in European adolescents located in urban settings. The data management systems, quality assurance monitoring activities, standardized manuals of operating procedures and training and study management are addressed in this paper. Various quality controls to ensure collection of valid and reliable data will be discussed in this supplement, as well as quantitative estimates of measurement error., Conclusion: The great advantage of the HELENA-CSS is the strict standardization of the fieldwork and the blood analyses, which precludes to a great extent the kind of immeasurable confounding bias that often interferes when comparing results from isolated studies.

Introduction: Analysis of several biological markers improves the quality and physiologic comprehension of data obtained in epidemiological nutritional studies., Aim: To develop a methodology that guarantees the centralized analysis and quality assurance of the most relevant blood parameters from fresh blood samples in adolescents in a European multicenter study., Materials and Methods: Stability of selected nutrients and biomarkers (vitamins, fatty acids, iron metabolism and immunological parameters) chosen with respect to time and temperature of sample transport and storage was evaluated as part of the pilot study of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) project., Results: Routine biochemistry and iron status parameters included in the HELENA Cross-Sectional Study (CSS) protocol could be analyzed within 24 h from fresh blood samples without any stability problems (coefficient of variation (CV)<5%, P<0.05). However, stability tests for lymphocyte subpopulations, vitamin C and fatty acids showed that they are very unstable at room temperature without any treatment. Therefore, a special handling for these samples was developed. Vitamin C was stabilized with metaphosphoric acid and transported under cooled conditions (CV 4.4%, recovery rate >93%, P>0.05). According to the results, a specific methodology and transport system were developed to collect blood samples at schools in 10 European cities and to send them to the centralized laboratory (IEL, Bonn, Germany). To guarantee good clinical practice, the field workers were instructed in a training workshop and a manual of operation was developed., Conclusion: The handling and transport system for fresh blood samples developed for the European multicenter study HELENA is adequate for the final part of the HELENA-CSS and will provide, for the first time, reference values for several biological markers in European adolescents.

Background: National and international recommendations for the intake of B vitamins in adolescents consist of estimates and extrapolations from adult values. Due to increasing growth and therefore relatively high energy and nutrient requirements adolescents are a vulnerable group from the nutritional point of view. In addition, a deficient intake of several B vitamins is strongly connected with the development of cancer, neural tube defects and cardiovascular diseases., Objective: The aim of this work is to assess dietary intake and status of B vitamins and homocysteine of European adolescents on the basis of published data., Methods: The database Medline (www.ncvi.nlm.nih.gov) was searched for terms like "Vitamin B", "homocysteine", "Europe", etc. Studies published between June 1980 and December 2004 were analysed for this review. Results of the intake of B vitamins were compared with the EAR or AI, respectively, as recommended by the U.S. Institute of Medicine. Due to lacking reference values for adolescents results of blood status as well as homocysteine were compared to different thresholds for adults., Results: Considering the limitations of the comparability between the reviewed studies e.g. by different methodologies, sample size, age groups, the average intake of B vitamins surpassed the EAR and AI. Boys were better supplied with B vitamins than girls. The intake decreased with increasing age in both genders. A possible deficiency of folate was noticed and girls in particular seemed to be more at risk. Clear regional tendencies for the vitamin intake could not be observed. Results of vitamin B6, B12, folate in blood, and homocysteine were levelled in-between the thresholds. Though the great standard deviation of folate increased the probability of a deficient supply in parts of the population., Conclusions: European girls seem to be at risk of folate deficiency. Supplements and fortified food were not taken into consideration by most of the published studies which additionally distorts the real intake. Standardized methods of dietary surveys and reference values for B vitamins as well as homocysteine still must be established. Hence, further investigations are of great relevance. folate increased the probability of a deficient supply in parts of the population., Conclusions: European girls seem to be at risk of folate deficiency. Supplements and fortified food were not taken into consideration by most of the published studies which additionally distorts the real intake. Standardized methods of dietary surveys and reference values for B vitamins as well as homocysteine still must be established. Hence, further investigations are of great relevance.