Association between adherence to the EAT-Lancet sustainable reference diet and cardiovascular health among European adolescents: the HELENA study

BACKGROUND

The EAT-Lancet Commission proposed a global reference diet to promote healthy diets within planetary boundaries. Studies evaluating the associations between the reference diet with health outcomes among adolescents are scarce. Thus, our aim was to assess the association between adherence to the EAT-Lancet diet and cardiovascular health among European adolescents.

METHODS

Data from the HELENA study were used. Usual dietary intake was assessed using two 24-h dietary recalls and adherence to the EAT-Lancet diet was assessed using the Planetary Health Diet Index (PHDI), a 16-component index that ranges from 0 to 150 points. Cardiovascular health was assessed through the seven-component Ideal Cardiovascular Health (ICH) score: never smoked, eutrophic body mass index, moderate-to-vigorous physical activity, healthy dietary pattern, low blood pressure, low fasting plasma glucose, and low total cholesterol. Total ICH score was categorized into ideal (5-7) and non-ideal (0-4).

RESULTS

A 10-point increment in the PHDI was associated with a lower probability of a non-ideal ICH status (OR 0.84, [95% CI: 0.75, 0.94]) among European adolescents, after adjusting for age, sex, socio-economic status, and total energy intake. Furthermore, a 10-point increment in the PHDI was associated with lower probability of high blood pressure (OR: 0.87 [0.79, 0.96]) and a lower probability of high blood cholesterol (OR: 0.88 [0.78, 0.99]).

CONCLUSION

Our study suggests that a higher PHDI may be associated with a better cardiovascular health status among European adolescents.

Digital media exposure and cognitive functioning in European children and adolescents of the I.Family study

The digital environment can pose health risks through exposure to unhealthy content. Yet, little is known about its relation to children's cognitive functioning. This study investigates the association between digital media (DM) exposure and children's cognitive functioning. This cross-sectional study is based on examinations of children aged 8-18 years (N = 8673) of the I.Family cohort (2013-2014). Exposure to television, computer, smartphone and internet was self-reported (hours/day). Media multitasking (MMT) was defined as simultaneous use of computers with other digital or non-screen-based activities. Standard instruments were used to assess cognitive inflexibility (score: 0-39), decision-making ability (- 100 to + 100) and impulsivity (12-48). Adjusted regression coefficients and 99.9%CIs were calculated by generalized linear mixed-effects models. In total, 3261 participants provided data for impulsivity, 3441 for cognitive inflexibility and 4046 for decision-making. Exposure to smartphones and media multitasking were positively associated with impulsivity (βsmartphone = 0.74; 99.9%CI = 0.42-1.07; βMMT = 0.73; 99.9%CI = 0.35-1.12) and cognitive inflexibility (βsmartphone = 0.32; 99.9%CI = -0.02-0.66; βMMT = 0.39; 99.9%CI = 0.01-0.77) while being inversely associated with decision-making ability. Extensive smartphone/internet exposure combined with low computer/medium TV exposure was associated with higher impulsivity and cognitive inflexibility scores, especially in girls. DM exposure is adversely associated with cognitive functioning in children and adolescents. Children require protection against the likely adverse impact of digital environment.

Correlates of bitter, sweet, salty and umami taste sensitivity in European children: Role of sex, age and weight status - The IDEFICS study

We aimed to describe differences in taste sensitivity in children according to age across 7- to 11-year-old children from eight European countries. We further compared taste sensitivity between boys vs. girls and under-/normal weight vs. overweight/obese children. Within the European multicentre IDEFICS (Identification and prevention of dietary and lifestyle-induced health effects in children and infants) study, 1938 school children participated in sweet, bitter, salty and umami detection threshold tests between 2007 and 2010, using the paired comparison staircase method. The lowest concentration at which the child was able to detect a difference to water was determined as taste detection threshold as a proxy of taste sensitivity. Mean taste thresholds were calculated stratified for sex, age groups, weight groups and country. BMI was calculated using measured height and weight; socio-demographic information was collected using questionnaires. Ordinal logistic regressions were conducted to investigate the association between sex, weight status (as categorical exposure variable) and age (as continuous exposure variable) and the taste sensitivity for the four taste modalities (as outcome), separately. Older children were more taste sensitive for sweet and salty and less taste sensitive for umami and bitter than younger children. Girls were more sensitive to sweet taste than boys. Overweight or obese children were less sensitive to sweet and salty taste compared to normal weight children This was the first study comparing taste sensitivity by measuring taste thresholds in children across different European countries. We conclude that taste thresholds are associated with weight status, children become more sensitive to sweet and salty tastes with increasing age, and girls might be more sensitive to sweet than boys.

Eating Behavior Associated with Food Intake in European Adolescents Participating in the HELENA Study

Adolescence is recognized as a time of rapid physiological and behavioral change. In this transition, eating behavior is still being formed and remains an integral part of a person’s lifestyle throughout his or her life. This study aims to assess eating behavior and associations with food intake in European adolescents. We included 2194 adolescents (45.9% boys), aged 12.5 to 17.5 years, from the cross-sectional HELENA study, with two completed 24 h recalls and complete questionnaire data on their eating behavior (Eating Behavior and Weight Problems Inventory for Children- EWI-C). Three subscales of the EWI were evaluated; they measured Strength and motivation to eat (EWI 1), Importance and impact of eating (EWI 2), and Eating as a means of coping with emotional stress (EWI 3). Since these subscales were specially focused on eating behavior, participants were classified as either Low (≤P75) or High (>P75) on each of the subscales. Our results showed a higher consumption of different types of food, in the EWI 1 scales, linked to the hunger and interest in eating, and we observed a relationship with the consumption of energy-dense products. This result was repeated in EWI 3, the subscale linked to emotional eating, where we also found higher consumption of energy-dense products. This study suggests that special features of eating behavior are associated with food intake in adolescents.

Media use trajectories and risk of metabolic syndrome in European children and adolescents: the IDEFICS/I.Family cohort

Background

Media use may influence metabolic syndrome (MetS) in children. Yet, longitudinal studies are scarce. This study aims to evaluate the longitudinal association of childhood digital media (DM) use trajectories with MetS and its components.

Methods

Children from Belgium, Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden participating in the IDEFICS/I.Family cohort were examined at baseline (W1: 2007/2008) and then followed-up at two examination waves (W2: 2009/2010 and W3: 2013/2014). DM use (hours/day) was calculated as sum of television viewing, computer/game console and internet use. MetS z-score was calculated as sum of age- and sex-specific z-scores of four components: waist circumference, blood pressure, dyslipidemia (mean of triglycerides and HDL-cholesterol⁻¹) and homeostasis model assessment for insulin resistance (HOMA-IR). Unfavorable monitoring levels of MetS and its components were identified (cut-off: ≥ 90^th percentile of each score). Children aged 2–16 years with ≥ 2 observations (W1/W2; W1/W3; W2/W3; W1/W2/W3) were eligible for the analysis. A two-step procedure was conducted: first, individual age-dependent DM trajectories were calculated using linear mixed regressions based on random intercept (hours/day) and linear slopes (hours/day/year) and used as exposure measures in association with MetS at a second step. Trajectories were further dichotomized if children increased their DM duration over time above or below the mean.

Results

10,359 children and adolescents (20,075 total observations, 50.3% females, mean age = 7.9, SD = 2.7) were included. DM exposure increased as children grew older (from 2.2 h/day at 2 years to 4.2 h/day at 16 years). Estonian children showed the steepest DM increase; Spanish children the lowest. The prevalence of MetS at last follow-up was 5.5%. Increasing media use trajectories were positively associated with z-scores of MetS (slope: β = 0.54, 95%CI = 0.20–0.88; intercept: β = 0.07, 95%CI = 0.02–0.13), and its components after adjustment for puberty, diet and other confounders. Children with increasing DM trajectories above mean had a 30% higher risk of developing MetS (slope: OR = 1.30, 95%CI = 1.04–1.62). Boys developed steeper DM use trajectories and higher risk for MetS compared to girls.

Conclusions

Digital media use appears to be a risk factor for the development of MetS in children and adolescents. These results are of utmost importance for pediatricians and the development of health policies to prevent cardio-metabolic disorders later in life.

Trial registration

ISRCTN, ISRCTN62310987. Registered 23 February 2018- retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01186-9.

Relative Validity of a Food and Beverage Preference Questionnaire to Characterize Taste Phenotypes in Children Adolescents and Adults

To assess the relative validity of our food and beverage preference questionnaire we investigated the association between sweet and fatty taste preference scores (assessed using a food and beverage preference questionnaire) and sweet and fatty food propensity scores (derived from a food frequency questionnaire). In I.Family, a large European multi-country cohort study, 12,207 participants from Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden, including 5291 adults, 3082 adolescents, and 3834 children, completed a food and beverage preference questionnaire with 63 items. Cumulative preference scores for sweet and fatty taste were calculated from the single item ranking ranging from 1 to 5. The relative consumption frequency of foods classified as sweet and fatty was used to calculate the corresponding consumption propensities, a continuous variable ranging from 0 to 100. We conducted regression analyses to investigate the association between sweet and fatty taste preference scores and sweet and fatty food propensity scores, respectively, separately for adults, adolescents ≥12 years, and for children <12 years. The overall sweet taste preference score was positively associated with the sweet food consumption propensity score (β = 2.4, 95% CI: 2.1;2.7) and the fatty taste preference score was positively associated with the fatty food consumption propensity score (β = 2.0, 95% CI: 1.8;2.2). After stratification for age (children <12 years, adolescents ≥12 years, and adults), the effect remained significant in all age groups and was strongest in adolescents and adults. We conclude that our food and beverage preference questionnaire is a useful instrument for epidemiological studies on sensory perception and health outcomes and for the characterization of sensory taste phenotypes.

Dietary calcium intake and adiposity in children and adolescents: Cross-sectional and longitudinal results from IDEFICS/I.Family cohort

BACKGROUND AND AIMS

Studies in children and adolescents suggest that higher dairy consumption may exert a protective effect on adiposity. However, only few studies examined the association between dietary calcium intake and body mass measures with conflicting results. We evaluated the association between total dietary calcium, calcium from dairy and non-dairy sources and anthropometric indices in a large European cohort of children and adolescents.

METHODS AND RESULTS

As many as 6,696 children belonging to the IDEFICS study were eligible for the cross-sectional analysis (Boys = 51%; age 6.0 ± 1.8 years; mean ± SD). Of these, 2,744 were re-examined six years later (Boys = 49.6%; age = 11.7 ± 1.8 years) in the framework of the I.Family study. The exposures were the baseline energy-adjusted total, dairy and non-dairy calcium intakes measured by a validated 24-h dietary recall. Multivariable linear regression was used to determine the association between calcium intake and z-scores of anthropometric indices (body mass index, BMI; waist circumference, WC; sum of skinfolds, SS; fat mass index, FMI) at baseline, and their variation over the 6 years follow-up. The association of dietary calcium with the incidence of overweight/obesity was also assessed. At baseline, an inverse association between total calcium intake and all the adiposity indices was consistently observed in boys, while only SS and FMI were significant in girls. The prevalence of overweight/obesity decreased significantly (P < 0.0001) across tertiles of calcium intake, in both sexes. Over the follow-up, boys with higher baseline calcium intake value showed significantly lower increase in BMI, WC and FMI z-scores, while in girls only a lower increase in WC z-score was observed. Only in boys, the risk to become overweight/obese decreased significantly across tertiles of calcium intake. Similar results were observed by analyzing only dietary calcium from dairy, while no association was observed between non-dairy calcium and adiposity indices.

CONCLUSIONS

We showed in a large cohort of European children and adolescents that dietary calcium intake may play a role in the modulation of body fat in developmental age. The association between dietary calcium and adiposity indices was driven by dairy calcium, while no effect was observed for non-dairy calcium intake. The existence of a sex-related difference in the association deserves further investigations.

Dietary sources of free sugars in the diet of European children: the IDEFICS Study

OBJECTIVE

To report dietary free sugars consumption and their different types and food sources in European children.

METHODS

The present study is based on the IDEFICS study, a European multicenter cohort study in children (2-9 years old) from eight countries, comprising 8308 children (51.4% males). Dietary intake of the previous 24 h was assessed using a computer-assisted 24-h dietary recalls (24-HDR) and the different types of sugars were assessed using the German food composition database.

RESULTS

Mean total energy intake was 1720 (SD 477) kcal/d for boys and 1631 (SD 451) kcal/d for girls. Total sugars intake was 98 (SD 52) g/day for boys and 93 (SD 49) g/day for girls. Free sugars intake was 81 (SD 49) g/day for boys and 77 (SD 47) g/day for girls. Girls had significantly lower intakes of energy, total and free sugars compared with than boys but did not differ in terms of percent of energy from total (23%) or free sugars (18%). There were large variations between countries in average % energy from free sugars (ranging from 13% in Italy to 27% in Germany). Less than 20% of children were within the recommended intake of 10% of energy from free sugars. The food groups that contributed substantially to free sugars intakes were "Fruit juices", "Soft drinks", "Dairy" and "Sweets and candies".

CONCLUSIONS

The contribution of free sugars to total energy intake in European children is higher than recommendations. The main food contributors to free sugars intake are sweetened beverages ("Fruit juices" and "Soft drinks"). It is especially important to reduce children's intake of free sugars, focusing in target population on certain foods and food groups.

Association between parental consumer attitudes with their children's sensory taste preferences as well as their food choice

Background

We investigated the association between the consumer attitudes of European parents and their children’s taste preferences and food choice. Furthermore, we studied whether the parental consumer attitudes were related to education level.

Methods

This analysis included 1,407 IDEFICS study children aged 6.0 to 11.8 years and from 7 European countries, who participated in the sensory taste perception module between 2007 and 2010. Parental consumer attitude was operationalized as ‘trusting in foods known from advertisements’ (trusting advertisements) and as ‘not avoiding additives in food’ (not avoiding additives). Parents reported their educational attainment and completed a food frequency questionnaire for their children. Consumption frequencies of sweet, fatty and processed foods as well as a healthy diet adherence score were calculated. Children performed fat, sweet and umami taste preference tests. Multivariable logistic models were used to analyse the association between parental consumer attitudes and their children’s taste preference frequencies as well as parental education. Linear regression models were used to analyse the association between parental consumer attitudes and their children’s food consumption.

Results

Parental consumer attitudes were not associated with children’s fat, sweet and umami taste preferences. Children of parents trusting advertisements consumed more frequently processed foods (β = 1.21, 95% CI: 0.49; 1.93). Children of parents not avoiding additives consumed more often sweet, fatty and processed foods and had a lower healthy diet adherence score (β = 2.37, 95% CI: 1.03; 3.70; β = 2.27, 95% CI: 1.12; 3.43; β = 0.91, 95% CI: 0.22; 1.59; β = -2.87, 95% CI: -3.89; -1.85, respectively). Unfavourable parental consumer attitudes were associated with a lower parental education level across Europe (Compared to high education: Odds Ratio (OR) of trusting advertisements with medium education: 1.04, 95% CI: 0.77; 1.40; OR with low education: 2.01, 95% CI: 1.15; 3.54; OR of not avoiding additives with medium education: 1.91, 95% CI: 1.44; 2.54; OR with low education: 1.76, 95% CI: 0.96; 3.24).

Conclusions

Across Europe, unfavourable parental consumer attitudes are associated with a lower diet quality of their children. Parental consumer attitudes in turn were associated with their own level of education. This has implications for policy makers, interventions and health promotion programmes that aim to promote healthy eating.

Dietary sources of sugars in adolescents' diet: the HELENA study

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.

Dietary Patterns in European and Brazilian Adolescents: Comparisons and Associations with Socioeconomic Factors

Associations between dietary patterns (DP) and socioeconomic factors have been little explored in adolescents. The aim of this study was to identify DP in European and Brazilian adolescents and to investigate their associations with a range of socioeconomic indicators. Adolescents from the HELENA-study and the Household Budget Survey were analyzed. Factor analysis was used to obtain DP. Linear regression was used to examine the association between DP and SES. In Europeans, the Western DP was associated with low education of the mother, high socioeconomic status (boys), older age (boys), and living in cities of the Northern Europe; in Brazilians, the Western DP was associated with high secondary education of the mother, high socioeconomic status and living in Southern areas of the country. The Traditional European DP, in both genders, was associated with high secondary education of the mother and inversely associated with a high socioeconomic status; the Traditional Brazilian DP, was associated with university level education of the mother and older age (boys). The association between DP and socioeconomic factors is relevant for the understanding of food-related practices and highlight the importance of performing a complete assessment of the socioeconomic influence in adolescent's DP from developed and developing countries.

Inflammation in metabolically healthy and metabolically abnormal adolescents: The HELENA study

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.

Familial aggregation and socio-demographic correlates of taste preferences in European children

Background

Studies on aggregation of taste preferences among children and their siblings as well as their parents are scarce. We investigated the familial aggregation of taste preferences as well as the effect of sex, age, country of residence and education on variation in taste preferences in the pan- European I.Family cohort.

Method

Thirteen thousand one hundred sixty-five participants from 7 European countries, comprising 2,230 boys <12 years, 2,110 girls <12 years, 1,682 boys ≥12 years, 1,744 girls ≥12 years and 5,388 parents, completed a Food and Beverage Preference Questionnaire containing 63 food items representing the taste modalities sweet, bitter, salty and fatty. We identified food items that represent the different taste qualities using factor analysis. On the basis of preference ratings for these food and drink items, a preference score for each taste was calculated for children and parents individually. Sibling and parent-child correlations for taste preference scores were calculated. The proportion of variance in children's preference scores that could be explained by their parents' preference scores and potential correlates including sex, age and parental educational was explored.

Results

Mean taste preferences for sweet, salty and fatty decreased and for bitter increased with age. Taste preference scores correlated stronger between siblings than between children and parents. Children's salty preference scores could be better explained by country than by family members. Children's fatty preference scores could be better explained by family members than by country. Age explained 17% of the variance in sweet and 16% of the variance in fatty taste preference. Sex and education were not associated with taste preference scores.

Conclusion

Taste preferences are correlated between siblings. Country could explain part of the variance of salty preference scores in children which points to a cultural influence on salt preference. Further, age also explained a relevant proportion of variance in sweet and fatty preference scores.

Physical activity, sedentary time, TV viewing, physical fitness and cardiovascular disease risk in adolescents: The HELENA study

BACKGROUND

To examine the independent associations between physical activity (PA) intensities, sedentary time (ST), TV viewing, cardiorespiratory fitness (CRF) and muscular fitness (MF) with cardiovascular disease (CVD) risk in youth.

METHODS

A cross-sectional study on 534 European adolescents (252 males, 282 females, 12.5-17.5years). Minutes per day of light (LPA), moderate (MPA) and vigorous (VPA) PA and total ST were measured using accelerometers. TV viewing time was measured using a questionnaire. CRF and MF were measured using the 20m shuttle run test and a hand dynamometer respectively. CVD outcomes included markers of body composition (body mass index (BMI), waist circumference (WC), WC/height (Ht) and sum of skinfolds (SumSF)), blood pressure, blood lipids and insulin resistance (HOMA-IR). Clustered CVD risk was calculated using SumSF, HOMA-IR, blood lipids and blood pressure.

RESULTS

LPA had a significant positive independent relationship with all body composition outcomes (P<0.001) and clustered CVD risk (P=0.046). VPA was negatively related to SumSF (P<0.001), BMI (P=0.018), WC/Ht (P=0.013) and clustered CVD risk (P=0.001), but was non-significant for all when other exposures were considered (P>0.10). MPA had a negative independent relationship with only WC (P=0.029) and ST was not significantly related to CVD risk (P>0.16). TV viewing had a significant positive independent relationship with HOMA-IR (P<0.001) and clustered CVD risk (P=0.019). CRF (all P<0.002) and MF (all P<0.009) had a negative independent relationship with body composition outcomes and clustered CVD risk.

CONCLUSIONS

Public health guidelines should prioritize on increasing levels of CRF, MF and VPA, and reducing TV viewing time to lower CVD risk in youth.

Ideal cardiovascular health and inflammation in European adolescents: The HELENA study

BACKGROUND AND AIMS

Inflammation plays a key role in atherosclerosis and this process seems to appear in childhood. The ideal cardiovascular health index (ICHI) has been inversely related to atherosclerotic plaque in adults. However, evidence regarding inflammation and ICHI in adolescents is scarce. The aim is to assess the association between ICHI and inflammation in European adolescents.

METHODS AND RESULTS

As many as 543 adolescents (251 boys and 292 girls) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study, a cross-sectional multi-center study including 9 European countries, were measured. C-reactive protein (CRP), complement factors C3 and C4, leptin and white blood cell counts were used to compute an inflammatory score. Multilevel linear models and multilevel logistic regression were used to assess the association between ICHI and inflammation controlling by covariates. Higher ICHI was associated with a lower inflammatory score, as well as with several individual components, both in boys and girls (p < 0.01). In addition, adolescents with at least 4 ideal components of the ICHI had significantly lower inflammatory score and lower levels of the study biomarkers, except CRP. Finally, the multilevel logistic regression showed that for every unit increase in the ICHI, the probability of having an inflammatory profile decreased by 28.1% in girls.

CONCLUSION

Results from this study suggest that a better ICHI is associated with a lower inflammatory profile already in adolescence. Improving these health behaviors, and health factors included in the ICHI, could play an important role in CVD prevention.

Fruit and vegetables consumption is associated with higher vitamin intake and blood vitamin status among European adolescents

BACKGROUND/OBJECTIVES

Current research in adults indicates that fruit and vegetable (FAV) consumption increases serum levels of vitamins C, E and folate of β-carotene and reduces homocysteine concentrations. The aim of the present study was to examine the association of FAV consumption on vitamin intakes and their impact on blood vitamin concentrations in European adolescents.

SUBJECT/METHODS

This multi-center cross-sectional study included 702 (53.7% females) adolescents, aged 12.50-17.49 years, from 10 European cities. Two independent self-administered 24 h dietary recalls were used to estimate the adolescent's diet. The total energy, vitamins and FAV consumption were calculated. Adolescents were categorized into three groups: (i) very low FAV intake (<200 g/day); (ii) low FAV consumption (200-399 g/day) and (iii) adequate FAV consumption (⩾400 g/day). Adolescent's fasted blood samples were taken for their analysis on vitamin concentrations.

RESULTS

The main results showed that those adolescents meeting the FAV recommendation, classified as FAV adequate consumers, presented higher intake of energy and some vitamins as B6, total folic acid, C, E and β-carotene compared with FAV very low consumers (P<0.05). Regarding their blood status, male adolescents who had a very low FAV consumption presented lower plasma folate, RBC folate blood concentrations compared with adequate FAV consumers (P<0.05). Female adequate FAV consumers had higher concentrations of pyridoxal phosphate (PLP), plasma folate, RBC folate, vitamin C, β-carotene and α-tocopherol compared with very low and low consumers (P<0.05).

CONCLUSIONS

Having a FAV dairy intake above 400 g/day is associated with higher vitamin intake and blood vitamin concentrations, especially for antioxidant and B-vitamins concentrations.

Fragmentation of daily rhythms associates with obesity and cardiorespiratory fitness in adolescents: The HELENA study

BACKGROUND & AIMS

Chronobiology studies periodic changes in living organisms and it has been proposed as a promising approach to investigate obesity. We analyze the association of the characteristics of the rest-activity rhythms with obesity, cardiorespiratory fitness and metabolic risk in adolescents from nine European countries.

METHODS

1044 adolescents (12.5-17.5 y) were studied. Circadian health was evaluated by actigraphy with accelerometers (Actigraph GT1M). Characteristics of the daytime activity such as fragmentation (intradaily variability), estimated acrophase, and 10 h mean daytime activity index were obtained. Body composition was assessed using Bioelectrical-Impedance-Analysis, skinfold thickness, air-displacement-plethysmography and Dual-energy-X-ray-Absorptiometry. Cardiorespiratory fitness (VO_2max) and metabolic risk were studied.

RESULTS

Highly fragmented activity rhythms were associated with obesity and central adiposity (P < 0.05). Obese adolescents had ∼3 times higher odds of having a high fragmentation of daytime activity compared to normal weight adolescents OR (95% CI) = 2.8 (1.170, 6.443). A highly fragmented rhythm was also related to lower cardiorespiratory fitness and higher metabolic risk (P < 0.05) so those adolescents classified as low fitness showed a significantly higher fragmentation of daytime activity than those included in the high fitness group (P < 0.0001). Other characteristics of the rhythms such as smaller 10 h daytime mean activity index and delayed estimated acrophase were also related to obesity and metabolic risk (P < 0.05).

CONCLUSIONS

Our results indicate that the daily organization of the rest-activity cycle is more fragmented in obese and less fit adolescents and correlates with higher metabolic risk. This fact reinforces our hypothesis that disturbances in daily rhythms can be considered as sensitive markers of poorer adolescent's health.

Dietary fat intake modifies the influence of the FTO rs9939609 polymorphism on adiposity in adolescents: The HELENA cross-sectional study

BACKGROUND AND AIMS

The fat mass and obesity associated gene (FTO) has been associated with obesity and dietary intake. The aims were: (i) To assess whether energy and macronutrient intakes were different across the FTOrs9939609 genotypes in adolescents, and (ii) to explore whether dietary fat intake modified the association of the rs9939609 polymorphism with adiposity.

METHODS AND RESULTS

The FTOrs9939609 polymorphism was genotyped in 652 adolescents (53% females, 14.8 ± 1.2 years, TT = 246, TA = 296, AA = 110). Energy and macronutrient intake were assessed by two non-consecutive 24 h-recalls. Weight, height, waist circumference and skinfold thicknesses were measured and body fat percent was calculated. Energy and macronutrient intake were similar across the FTOrs9939609 genotypes (P > 0.2). There were significant interactions between the FTO polymorphism and fat intake on adiposity estimates (P < 0.05). In adolescents whose fat intake was below 30% (N = 203), the A allele of rs9939609 was not associated with adiposity indices. In contrast, in adolescents whose fat intake was between 30% and 35% of energy (N = 190), the rs9939609 polymorphism was associated with a 1.9% higher body fat per risk allele (95%CI: 0.39, 3.33; P < 0.05), and in those whose fat intake was higher than 35% (N = 259), it was associated with a 2.8% higher body fat per risk allele (95%CI: 1.27, 4.43; P < 0.001).

CONCLUSIONS

These findings support the concept that the deleterious effect of the FTOrs9939609 polymorphism on adiposity is exacerbated in adolescents consuming high fat diets. In contrast, the consumption of low fat diets (<30% of energy) may attenuate the genetic predisposition to obesity in risk allele carriers.

Bidirectional associations between psychosocial well-being and body mass index in European children: longitudinal findings from the IDEFICS study

Background

The negative impact of childhood overweight on psychosocial well-being has been demonstrated in a number of studies. There is also evidence that psychosocial well-being may influence future overweight. We examined the bidirectional association between childhood overweight and psychosocial well-being in children from a large European cohort.

The dual aim was to investigate the chronology of associations between overweight and psychosocial health indicators and the extent to which these associations may be explained by parental education.

Methods

Participants from the IDEFICS study were recruited from eight countries between September 2007 and June 2008 when the children were aged 2 to 9.9 years old. Children and families provided data on lifestyle, psychosocial well-being, and measured anthropometry at baseline and at follow-up 2 years later. This study includes children with weight, height, and psychosocial well-being measurements at both time points (n = 7,831). Psychosocial well-being was measured by the KINDL® and Strengths and Difficulties Questionnaire respectively. The first instrument measures health-related quality of life including emotional well-being, self-esteem, parent relations and social relations while the second measures well-being based on emotional symptoms, conduct problems and peer-related problems. Logistic regression was used for modeling longitudinal associations.

Results

Children who were overweight at baseline had increased risk of poor health-related quality of life (odds ratio (OR) = 1.23; 95 % confidence interval (CI):1.03–1.48) measured 2 years later; this association was unidirectional. In contrast to health-related quality of life, poor well-being at baseline was associated with increased risk of overweight (OR = 1.39; 95 % CI:1.03–1.86) at 2 year follow-up; this association was also only observed in one direction. Adjustment for parental education did not change our findings.

Conclusion

Our findings indicate that the association between overweight and psychosocial well-being may be bidirectional but varies by assessment measures. Future research should further investigate which aspects of psychosocial well-being are most likely to precede overweight and which are more likely to be consequences of overweight.

Longitudinal associations of lifestyle factors and weight status with insulin resistance (HOMA-IR) in preadolescent children: the large prospective cohort study IDEFICS

Background

This study investigates prospective associations of anthropometrical and lifestyle indices with insulin resistance (IR) in European children from the IDEFICS cohort. Insulin resistance (IR) is a growing concern in childhood obesity and a central aspect of the metabolic syndrome (MS). It most likely represents the link between obesity and type 2 diabetes.

Methods

This longitudinal study included 3348 preadolescent children aged 3 to 10.9 years from 8 European countries who were observed from 2007/2008 to 2009/2010. The main outcome measure in the present analysis is HOMA-IR (homeostasis model assessment as a common proxy indicator to quantify IR) at follow-up and in its longitudinal development. Anthropometrical measures and lifestyle indices, including objectively determined physical activity, were considered, among others factors, as determinants of IR. Prospective associations between IR at follow-up and anthropometrical and lifestyle indices were estimated by logistic regression models.

Results

Country-specific prevalence rates of IR in the IDEFICS cohort of European children showed a positive trend with weight category. Prospective multivariate analyses showed the strongest positive associations of IR with BMI z-score (OR = 2.6 for unit change from the mean, 95 % CI 2.1–3.1) and z-score of waist circumference (OR = 2.2 for unit change from the mean, 95 % CI 1.9–2.6), which were analysed in separate models, but also for sex (OR = 2.2 for girls vs. boys, 95 % CI 1.5–3.1 up to OR 2.5, 95 % CI 1.8–3.6 depending on the model), audio-visual media time (OR = 1.2 for an additional hour per day, 95 % CI 1.0–1.4 in both models) and an inverse association of objectively determined physical activity (OR = 0.5 for 3^rd compared to 1^st quartile, 95 % CI 0.3–0.9 in both models). A longitudinal reduction of HOMA-IR was accompanied with a parallel decline in BMI.

Conclusions

This study is, to our knowledge, the first prospective study on IR in a preadolescent children’s population. It supports the common hypothesis that overweight and obesity are the main determinants of IR. Our data also indicate that physical inactivity and a sedentary lifestyle are likewise associated with the development of IR, independent of weight status. The promotion of physical activity should thus be considered as an equal option to dietary intervention for the treatment of IR in the paediatric practice.

Influence of physical fitness on cardio-metabolic risk factors in European children. The IDEFICS study

OBJECTIVE

The aim of the study was to assess the associations of individual and combined physical fitness components with single and clustering of cardio-metabolic risk factors in children.

SUBJECTS/METHODS

This 2-year longitudinal study included a total of 1635 European children aged 6-11 years. The test battery included cardio-respiratory fitness (20-m shuttle run test), upper-limb strength (handgrip test), lower-limb strength (standing long jump test), balance (flamingo test), flexibility (back-saver sit-and-reach) and speed (40-m sprint test). Metabolic risk was assessed through z-score standardization using four components: waist circumference, blood pressure (systolic and diastolic), blood lipids (triglycerides and high-density lipoprotein) and insulin resistance (homeostasis model assessment). Mixed model regression analyses were adjusted for sex, age, parental education, sugar and fat intake, and body mass index.

RESULTS

Physical fitness was inversely associated with clustered metabolic risk (P<0.001). All coefficients showed a higher clustered metabolic risk with lower physical fitness, except for upper-limb strength (β=0.057; P=0.002) where the opposite association was found. Cardio-respiratory fitness (β=-0.124; P<0.001) and lower-limb strength (β=-0.076; P=0.002) were the most important longitudinal determinants. The effects of cardio-respiratory fitness were even independent of the amount of vigorous-to-moderate activity (β=-0.059; P=0.029). Among all the metabolic risk components, blood pressure seemed not well predicted by physical fitness, while waist circumference, blood lipids and insulin resistance all seemed significantly predicted by physical fitness.

CONCLUSION

Poor physical fitness in children is associated with the development of cardio-metabolic risk factors. Based on our results, this risk might be modified by improving mainly cardio-respiratory fitness and lower-limb muscular strength.

Effects of clustering of multiple lifestyle-related behaviors on blood pressure in adolescents from two observational studies

BACKGROUD

Several lifestyle-related behaviors are associated with cardiovascular health outcomes in adolescents. To examine the associations between clustered lifestyle-related behaviors and blood pressure (BP) levels in adolescents.

METHODS

Participants were recruited by multistage random cluster in two cross-sectional studies; one conducted in 2006 and 2007 in ten cities from nine European countries: Athens and Heraklion in Greece, Dortmund in Germany, Ghent in Belgium, Lille in France, Pécs in Hungary, Rome in Italy, Stockholm in Sweden, Vienna in Austria, and Zaragoza in Spain; and another conducted in 2007 one city in Brazil (Maringá/PR). Systolic BP (SBP) and diastolic BP (DBP) (outcomes) and clustered behaviors (weekly consumption of fruits and vegetables, weekly consumption of sugar-sweetened beverages, sleep duration, screen time and physical activity) were analyzed.

RESULTS

The Healthy Eating cluster was negatively associated with DBP in European girls, β=-2.46 (-4.62; -0.30), and with SBP in Brazilian boys, β=-2.79 (-3.10; -0.15). Furthermore, the Unhealthy Eating cluster was associated with increased SBP in European girls, β=4.54 (1.29; 7.79), and in Brazilian boys, β=4.10 (0.80; 7.40).

CONCLUSION

The Healthy Eating cluster was associated with lower blood pressure, whereas the Unhealthy Eating cluster was associated with increased SBP in adolescents.

Physical Activity Is Associated with Attention Capacity in Adolescents

OBJECTIVE

To assess the relationships among physical activity, measured objectively, and attention capacity in European adolescents.

STUDY DESIGN

The study included 273 adolescents, aged 12.5-17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Participants wore a uniaxial accelerometer for 7 days to measure physical activity. The d2 Test of Attention was administered to assess attention capacity. Multivariate analyses were used to study the association of attention capacity with each measure of physical activity. Receiver operating characteristic analysis was performed to determine thresholds that best discriminate between low and good attention capacity.

RESULTS

After controlling for potential confounding variables (age, sex, body mass index, parental educational level, fat mass, aerobic fitness, and center), adolescents' attention capacity test performances were significantly and positively associated with longer time spent in moderate or moderate-to-vigorous physical activity (MVPA) in free-living conditions (P < .05). Receiver operating characteristic curve analyses revealed that the physical activity thresholds that best discriminated between low/good attention capacities were ≥41 min·day(-1) for moderate, ≥12 min·day(-1) for vigorous, and ≥58 min·day(-1) for MVPA.

CONCLUSION

These findings suggest that promoting MVPA may be have a beneficial effect on attention capacity, an important component of cognition, in adolescents.

Dietary Carbohydrate and Nocturnal Sleep Duration in Relation to Children's BMI: Findings from the IDEFICS Study in Eight European Countries

Previous research has found an association between being overweight and short sleep duration. We hypothesized that this association could be modified by a high carbohydrate (HC) diet and that the timing and type (starch or sugar) of intake may be an important factor in this context. Participants in the prospective, eight-country European study IDEFICS were recruited from September 2007 to June 2008, when they were aged two to nine years. Data on lifestyle, dietary intake and anthropometry were collected on two occasions. This study included 5944 children at baseline and 4301 at two-year follow-up. For each meal occasion (morning, midday, and evening), starch in grams and sugar in grams were divided by total energy intake (EI), and quartiles calculated. HC-starch and HC-sugar intake categories were defined as the highest quartile for each meal occasion. In a mutually adjusted linear regression model, short sleep duration as well as HC-starch in the morning were positively associated with body mass index (BMI) z-scores at baseline. HC-starch at midday was positively associated with body mass index (BMI) z-scores in children with short sleep duration, and negatively associated with BMI z-scores in those with normal sleep. After adjustment for baseline BMI z-scores, associations between total HC from starch or sugar and high BMI z-scores at two-year follow-up did not persist. Our observations offer a perspective on optimal timing for macronutrient consumption, which is known to be influenced by circadian rhythms. Reduced carbohydrate intake, especially during morning and midday meals, and following nocturnal sleep duration recommendations are two modifiable factors that may protect children from being overweight in the future.

Liver enzymes and clustering cardiometabolic risk factors in European adolescents: the HELENA study

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.

Association between bone stiffness and nutritional biomarkers combined with weight-bearing exercise, physical activity, and sedentary time in preadolescent children. A case-control study

Physical activity (PA) and micronutrients such as calcium (Ca), vitamin D (25OHD), and phosphate (PO) are important determinants of skeletal development. This case-control study examined the association of these nutritional biomarkers and different PA behaviours, such as habitual PA, weight-bearing exercise (WBE) and sedentary time (SED) with bone stiffness (SI) in 1819 2-9-year-old children from the IDEFICS study (2007-2008). SI was measured on the calcaneus using quantitative ultrasound. Serum and urine Ca and PO and serum 25OHD were determined. Children's sports activities were reported by parents using a standardised questionnaire. A subsample of 1089 children had accelerometer-based PA data (counts per minute, cpm). Moderate-to-vigorous PA (MVPA) and SED were estimated. Children with poor SI (below the 15th age-/sex-/height-specific percentile) were defined as cases (N=603). Randomly selected controls (N=1216) were matched by age, sex, and country. Odds ratios (OR) for poor SI were calculated by conditional logistic regression for all biomarkers and PA behaviour variables separately and combined (expressed as tertiles and dichotomised variables, respectively). ORs were adjusted for fat-free mass, dairy product consumption, and daylight duration. We observed increased ORs for no sports (OR=1.39, p<0.05), PA levels below 524 cpm (OR=1.85, p<0.05) and MVPA below 4.2% a day (OR=1.69, p<0.05) compared to WBE, high PA levels (<688 cpm) and high MVPA (6.7%), respectively. SED was not associated with SI. ORs were moderately elevated for low serum Ca and 25OHD. However, biomarkers were not statistically significantly associated with SI and did not modify the association between PA behaviours and SI. Although nutritional biomarkers appear to play a minor role compared to the osteogenic effect of PA and WBE, it is noteworthy that the highest risk for poor SI was observed for no sports or low MVPA combined with lower serum Ca (<2.5 mmol/l) or lower 25OHD (<43.0 nmol/l).

Dietary protein and amino acids intake and its relationship with blood pressure in adolescents: the HELENA STUDY

OBJECTIVE

To analyze the association between dietary protein and amino acids intake and systolic (SBP) and diastolic (DBP) blood pressure in European adolescents.

METHODS

Participants were from the cross-sectional study performed in Europe, Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA study; n = 1605; 12.5-17.5 years; 833 girls) selected by complex sampling. The associations between dietary protein and amino acids intake and SBP/DBP were examined by multilevel linear regression models (context variable by school); the analysis being stratified by sex. Cities, seasonality, age, socioeconomic level, parental education level, body mass index, waist circumference, Tanner stage and physical activity were used as covariates.

RESULTS

In boys, we found an inverse association between protein (animal and vegetable) intake and DBP; and a positive association between histidine and SBP. In girls, we observed a positive association among tryptophan, histidine with SBP and methionine with DBP. On the other hand, we observed an inverse association between tyrosine and both SBP and DBP levels in girls.

CONCLUSIONS

The association between amino acids and BP levels is controversial and depends on the type of amino acids, and protein intake can help control the DBP in boys.

Inflammation profile in overweight/obese adolescents in Europe: an analysis in relation to iron status

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.

Physical activity modifies the associations between genetic variants and blood pressure in European adolescents

We hypothesized that physical activity and sedentary behavior could modify the associations between known genetic variants blood pressure-associated genes in European adolescents. Meeting current physical activity recommendations (≥ 60 minutes/day) was able attenuate the deleterious effect of the NOS3 rs3918227 polymorphism on systolic blood pressure in European adolescents.

Muscular fitness, fatness and inflammatory biomarkers in adolescents

BACKGROUND

Muscular fitness, cardiorespiratory fitness (CRF) and fatness are mutually related with chronic inflammation.

PURPOSE

To examine the independent association of muscular fitness with inflammatory biomarkers in adolescents from nine European countries.

METHODS

A total of 639 adolescents (296 boys) aged from 12.5 to 17.5 year were included in this report. Data collection took place in 2006-2007 and analyses in 2012. A muscular fitness score was computed from handgrip strength and standing long jump. CRF was measured using the 20 m shuttle run test. Z-scores of C-reactive protein, complement factors C3 and C4, leptin and white blood cell counts were summed to create a cluster of inflammatory biomarkers. Sex, age, pubertal stage and centre were used as main confounders. Additional models were further adjusted for insulin resistance (HOMA-IR) and sum of four skinfolds.

RESULTS

Muscular fitness was negatively associated with single and clustered inflammatory biomarkers (standardized β from -0.399 to -0.100, all P-values < 0.05). Additional adjustments for CRF and HOMA-IR weakened the associations, but they still remained significant. The association was no longer significant when adjusting for skinfolds. Decreasing values of inflammatory score were observed across incremental levels of muscular fitness in both non-overweight and overweight adolescents (P ≤ 0.05).

CONCLUSIONS

Adolescents with higher levels of muscular fitness present a lower chronic inflammation, and this seems to be explained by lower levels of fatness. Yet, overweight and obese adolescents may exhibit a less adverse profile if they maintain appropriate levels of muscular fitness.

Physical activity and sedentary behaviour in European children: the IDEFICS study

OBJECTIVE

To estimate the prevalence of physical activity and sedentary behaviours in European children, and to evaluate the relationship between media availability in personal space and physical activity in relation to total screen time.

DESIGN

Data from the baseline IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) cross-sectional survey. Information on hours of television/digital video disk/video viewing and computer/games-console use (weekday and weekend days), media device availability in personal space, sports club membership, hours of active organized play and commuting (to and from school) were assessed via a self-reported parental questionnaire. Total screen time was defined as the sum of daily media use and subsequently dichotomized into meeting or not meeting the guidelines of the American Academy of Pediatrics.

SETTING

Eight survey centres (Italy, Estonia, Cyprus, Belgium, Sweden, Germany, Hungary and Spain).

SUBJECTS

Children (n 15 330; 51% males) aged 2-10 years.

RESULTS

Percentage of children engaged in total screen time for >2 h/d was higher on weekend days (52% v. 20% on weekdays) and in the older group (71% in males; 57% in females), varying by country. Children with a television set in their bedroom were more likely not to meet the screen time recommendations (OR = 1·54; 95% CI 1·60, 1·74).

CONCLUSIONS

Approximately a third of the children failed to meet current screen time recommendations. Availability of a television set in personal space increased the risk of excess total screen time. This information could be used to identify potential targets for public health promotion actions of young population groups.

Family structure and childhood obesity: results of the IDEFICS Project

OBJECTIVE

To analyse the association between family structure and adiposity in children.

DESIGN

Cross-sectional and longitudinal analysis of the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort.

SETTING

Primary schools and kindergartens.

SUBJECTS

Children (n 12 350; aged 7·9 (SD 1·8) years) for the cross-sectional analysis and children (n 5236; at baseline: normal weight, aged 5·9 (SD 1·8) years) for the longitudinal study underwent anthropometry. Family structure was analysed as (i) number and type of cohabiting adults and (ii) number of siblings.

RESULTS

In the cross-sectional analysis, after controlling for covariates, children living with grandparents had significantly higher BMI Z-score than those living with both parents (0·63; 95% CI 0·33, 0·92 v. 0·19; 95% CI 0·17, 0·22; P < 0·01); in addition, the higher the number of siblings, the lower the BMI Z-score (only child = 0·31; 95% CI 0·24, 0·38; 1 sibling = 0·19; 95% CI 0·16, 0·23; 2 siblings = 0·15; 95% CI 0·09, 0·20; >2 siblings = 0·07, 95% CI 0·04, 0·19; P < 0·001). Over the 2-year follow-up, differences in weight gain were observed across family-structure categories. Further, the risk of incidence of overweight/obesity was significantly lower the higher the number of siblings living in the household (v. only child: 1 sibling = 0·74, 95% CI 0·57, 0·96; 2 siblings = 0·63, 95% CI 0·45, 0·88; >2 siblings = 0·40, 95% CI 0·21, 0·77), independently of confounders.

CONCLUSIONS

The study suggests that an independent association between family structure and childhood obesity exists.

Association of breakfast consumption with objectively measured and self-reported physical activity, sedentary time and physical fitness in European adolescents: the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

OBJECTIVE

To examine the association of breakfast consumption with objectively measured and self-reported physical activity, sedentary time and physical fitness.

DESIGN

The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Cross-Sectional Study. Breakfast consumption was assessed by two non-consecutive 24 h recalls and by a 'Food Choices and Preferences' questionnaire. Physical activity, sedentary time and physical fitness components (cardiorespiratory fitness, muscular fitness and speed/agility) were measured and self-reported. Socio-economic status was assessed by questionnaire.

SETTING

Ten European cities.

SUBJECTS

Adolescents (n 2148; aged 12·5-17·5 years).

RESULTS

Breakfast consumption was not associated with measured or self-reported physical activity. However, 24 h recall breakfast consumption was related to measured sedentary time in males and females; although results were not confirmed when using other methods to assess breakfast patterns or sedentary time. Breakfast consumption was not related to muscular fitness and speed/agility in males and females. However, male breakfast consumers had higher cardiorespiratory fitness compared with occasional breakfast consumers and breakfast skippers, while no differences were observed in females. Overall, results were consistent using different methods to assess breakfast consumption or cardiorespiratory fitness (all P ≤ 0·005). In addition, both male and female breakfast skippers (assessed by 24 h recall) were less likely to have high measured cardiorespiratory fitness compared with breakfast consumers (OR = 0·33; 95% CI 0·18, 0·59 and OR = 0·56; 95%CI 0·32, 0·98, respectively). Results persisted across methods.

CONCLUSIONS

Skipping breakfast does not seem to be related to physical activity, sedentary time or muscular fitness and speed/agility as physical fitness components in European adolescents; yet it is associated with both measured and self-reported cardiorespiratory fitness, which extends previous findings.

Vitamins and iron blood biomarkers are associated with blood pressure levels in European adolescents. The HELENA study

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.

Health inequalities in urban adolescents: role of physical activity, diet, and genetics

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.

A favorable built environment is associated with better physical fitness in European adolescents

OBJECTIVE

To assess the association between the built environment and physical fitness and physical activity in adolescents.

METHODS

The study included 3528 adolescents, aged 12.5-17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study. The health-related physical fitness components were assessed using the physical fitness tests. Participants wore a uniaxial accelerometer (ActiGraph®) for 7 days to measure physical activity. A specific questionnaire addressing the built environment was used. Potential confounding factors including age, gender, body mass index, body composition, pubertal status, smoking, educational level of parents, and socioeconomic status were analyzed using backward stepwise linear regression analysis.

RESULTS

Heavy traffic in the neighborhood was the strongest factor negatively associated with both physical fitness and physical activity (both P<0.05). Conversely, a secure bicycling or walking route from home to school was positively associated with various components of physical fitness and physical activity (P<0.01). Outdoor fields and gymnasiums near home were also associated with better physical fitness (P<0.01), but not with physical activity.

CONCLUSIONS

A favorable built environment may contribute to health-related physical fitness and physical activity of adolescents and should be considered in future interventions and health promotion strategies.

Sedentary behaviour and clustered metabolic risk in adolescents: the HELENA study

BACKGROUND AND AIMS

Although sedentary behaviours are linked with mortality for cardiovascular reasons, it is not clear whether they are negatively related with cardio-metabolic risk factors. The aim was to examine the association between time engaged in television (TV) viewing or playing with videogames and a clustered cardio-metabolic risk in adolescents.

METHODS AND RESULTS

Sedentary behaviours and physical activity were assessed in 769 adolescents (376 boys, aged 12.5-17.5 years) from the HELENA-CSS study. We measured systolic blood pressure, HOMA index, triglycerides, TC/HDL-c, VO₂max and the sum of four skinfolds, and a clustered metabolic risk index was computed. A multilevel regression model (by Poisson) was performed to calculate the prevalence ratio of having a clustered metabolic risk. In boys, playing >4 h/day with videogames (weekend) and moderate to vigorous PA (MVPA) was associated with cardio-metabolic risk after adjustment for age, maternal education and MVPA. In contrast, TV viewing was not associated with the presence of cardio-metabolic risk.

CONCLUSION

In boys, playing with videogames may impair cardio-metabolic health during the adolescence. Adolescents should be encouraged to increase their participation in physical activity of at least moderate intensity to obtain a more favourable risk factor profile.