Association of Fat Mass with Bone Mineral Content in Female Adolescents

Obesity Research. Jul, 2002  |  Pubmed ID: 12105295

Harmonization of Anthropometric Measurements for a Multicenter Nutrition Survey in Spanish Adolescents

Nutrition (Burbank, Los Angeles County, Calif.). Jun, 2003  |  Pubmed ID: 12781845

Although the need for accurate anthropometric measurement has been repeatedly stressed, reports on growth and physical measurements in human populations rarely include estimates of measurement error. We describe the standardization process and reliability of anthropometric measurements carried out in a pilot study.

Physical Activity and Fatness in Prepubertal Children

The American Journal of Clinical Nutrition. Jun, 2003  |  Pubmed ID: 12791634

Gender Differences in Newborn Subcutaneous Fat Distribution

European Journal of Pediatrics. Aug, 2004  |  Pubmed ID: 15168110

The pattern and distribution of subcutaneous fat in term and preterm newborns has been assessed by skinfold thicknesses (ST), describing gender and gestational age variations. Weight, length and ST (triceps, biceps, subscapular and suprailiac) were measured in 4634 neonates (2445 males and 2189 females) aged from 32 to 41 gestational weeks. Central to total skinfold ratio (CTS), (suprailiac + subscapular)/sum of 4 ST, was calculated. Males were heavier and longer than females. The sum of 4 ST and CTS was higher in females at every gestational age (with significant differences from 35 weeks) and also the sum of 4 ST per kg body weight (P < 0.05 from 32-33 weeks). Throughout the gestational period, ST increased significantly (P < 0.0001) but CTS did not show variations, neither in males nor in females. CONCLUSION: term and preterm females have a more centralised pattern and more amount of subcutaneous fat than males. Central to total skinfold ratio must be considered as an index of centripetal fat store which is independant of gestational age.

Overweight, Obesity and Body Fat Composition in Spanish Adolescents. The AVENA Study

Annals of Nutrition & Metabolism. Mar-Apr, 2005  |  Pubmed ID: 15802900

To describe the prevalence of overweight and obesity in the Spanish adolescent population and its relationship with the socioeconomic status, and to assess their body fat composition and compare these results with previous data from our own country.

Cardiac Findings in Adolescents with Anorexia Nervosa at Diagnosis and After Weight Restoration

European Journal of Pediatrics. Jun, 2005  |  Pubmed ID: 15909184

The aim of this study was to compare heart abnormalities in a group of young women with anorexia nervosa at diagnosis and after weight restoration. A total of 40 young women with anorexia nervosa were evaluated, at baseline, (diagnosis) and follow-up (9 to 18 months later) and matched with 40 healthy women of the same age and of normal weight. QT interval was measured from surface electrocardiograms. QT dispersion was defined as the difference between maximum QT and minimum QT occurring in any of the 12 leads. Left ventricular end-diastolic diameter, left ventricular end-systolic diameter, left ventricular mass, left ventricular mass index, cardiac output, fractional shortening and fractional ejection, were measured by echocardiography. In anorexia nervosa patients, corrected QT interval and QT dispersion, significantly decreased from baseline to follow-up. Left ventricular end-diastolic dimension, left ventricular mass index, and cardiac output, in anorexia nervosa were significantly lower at diagnosis than at follow-up after weight restoration. CONCLUSION: Adolescents with anorexia nervosa have significant functional and structural cardiac abnormalities; weight gain was associated with improvement. Appropriate attention should be paid to cardiac involvement.

[Low Level of Physical Fitness in Spanish Adolescents. Relevance for Future Cardiovascular Health (AVENA Study)]

Revista Española De Cardiología. Aug, 2005  |  Pubmed ID: 16053823

Several studies have demonstrated that physical fitness in childhood and adolescence is related to cardiovascular risk in adulthood. Current data on the physical fitness of Spanish adolescents are not available. Therefore, the aims of this study were: a) to assess the physical fitness of Spanish adolescents and establish reference values for use in health and educational settings as indicators of cardiovascular health, and b) to determine the percentage of Spanish adolescents below the minimum level of aerobic fitness needed to guarantee future cardiovascular health.

Osteogenic Alveolar Distraction: a Review of the Literature

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics. Jan, 2006  |  Pubmed ID: 16360604

Alveolar distraction is a relatively novel procedure by which alveolar bone and underlying mucosa are regenerated. The low predictability of other vertical or horizontal bone regeneration methods has increased interest in this promising technique. This article was designed to review published clinical and experimental results on alveolar distraction, including basic research in other disciplines (maxillofacial and orthopedic distraction) related to or with influence on alveolar distraction.

Early Programming of Body Composition and Fat Distribution in Adolescents

The Journal of Nutrition. Jan, 2006  |  Pubmed ID: 16365074

Size at birth and early postnatal growth are determinants of adult height and BMI. The aim of this study was to evaluate the effect of birth weight on body composition and fat distribution in a group of Spanish adolescents. Current body composition was assessed by both skinfold thickness and dual X-ray absorptiometry in 234 adolescents born at term (140 girls and 94 boys), now aged 13-18 y and living in the city of Zaragoza. Relative fat distribution was estimated using the ratio of the subscapular to triceps skinfolds (S:T). Birth weight and gestational age were assessed by a questionnaire. Birth weight was inversely associated with the S:T ratio (P < 0.05) in boys and directly associated with bone mass (P < 0.01) and fat-free mass (P < 0.05) in girls. This association was independent of factors such as age, Tanner stage, gestational age, socioeconomic status, physical activity, and height. In conclusion, our data support the hypothesis that impaired fetal growth, measured by birth weight, may be related to central fat distribution in boys and decreased bone and fat-free mass in girls.

Aerobic Physical Fitness in Relation to Blood Lipids and Fasting Glycaemia in Adolescents: Influence of Weight Status

Nutrition, Metabolism, and Cardiovascular Diseases : NMCD. May, 2006  |  Pubmed ID: 16679221

We explored the associations between aerobic physical fitness with blood lipids and a composite index of blood lipids and fasting glycaemia in adolescents, analysing possible interactions with weight status.

Is Dietary Intake Able to Explain Differences in Body Fatness in Children and Adolescents?

Nutrition, Metabolism, and Cardiovascular Diseases : NMCD. May, 2006  |  Pubmed ID: 16679222

Obesity is the result of an imbalance between energy intake and energy expenditure. Controversial information exists about what are the strongest energy balance aspects influencing body fatness. This article is focused on food consumption facts that could be related to the risk of being obese in children and adolescents. It reviews whether energy intake, macronutrient composition of diet, eating patterns or other dietary intake factors are able to explain differences in body composition when obesity has been already developed or even in subjects at risk to become obese. There is not enough evidence to clarify the importance of diet on overweight children and adolescents, and conclusions derived are somewhat controversial. Cross-sectional and longitudinal studies do not show clear relationships between energy intake or food composition and body fatness. To find relations between dietary factors and childhood obesity perhaps eating patterns or different types of foods must be considered: meal patterns and meal frequency, snacking and beverage consumption, fast food intake, portion sizes, etc. There is no clear association between different aspects of dietary intake and the development of obesity in children and adolescents. Longitudinal and experimental studies are needed in the future.

Inflammatory Proteins Are Related to Total and Abdominal Adiposity in a Healthy Adolescent Population: the AVENA Study

The American Journal of Clinical Nutrition. Sep, 2006  |  Pubmed ID: 16960163

In adults, obesity is characterized by a state of chronic low-grade inflammation accompanied by moderately high concentrations of acute phase inflammatory proteins. Recent results regarding C-reactive protein (CRP) point to a similar status in adolescents; however, studies of associations of the serum inflammatory proteins CRP, ceruloplasmin, and complement factors C3 and C4 with body fat distribution remain scarce.

Screening Performances of the International Obesity Task Force Body Mass Index Cut-off Values in Adolescents

Journal of the American College of Nutrition. Oct, 2006  |  Pubmed ID: 17031009

To try to improve the International Obesity Task Force (IOTF) BMI cut-off values, in terms of prediction of body fat percentage assessed by dual-energy X-ray absorptiometry (DXA), in adolescents.

Interventions to Improve Cardiovascular Risk Factors in Obese Children

Journal of Pediatric Gastroenterology and Nutrition. Oct, 2006  |  Pubmed ID: 17033516

Anthropometric Determinants of a Clustering of Lipid-related Metabolic Risk Factors in Overweight and Non-overweight Adolescents--influence of Cardiorespiratory Fitness. The Avena Study

Annals of Nutrition & Metabolism. 2006  |  Pubmed ID: 17191028

To explore in adolescents the associations between simple anthropometric variables with a continuously distributed summary score for lipid-related metabolic risk in both overweight and non-overweight adolescents, and to test whether these associations are modified by the level of cardiorespiratory fitness.

Reference Values for Serum Lipids and Lipoproteins in Spanish Adolescents: the AVENA Study

Sozial- Und Präventivmedizin. 2006  |  Pubmed ID: 18027788

To provide current reference values for serum lipid and lipoprotein levels in Spanish adolescents according to age and sex.

Limitations of the Current World Health Organization Growth References for Children and Adolescents

Food and Nutrition Bulletin. Dec, 2006  |  Pubmed ID: 17361655

Since the 1970s, the World Health Organization (WHO) has recommended the use of the growth references developed by the United States National Center for Health Statistics (NCHS) based on national survey data collected in the 1960s and 1970s. These references are known as the WHO or NCHS/WHO growth references. Over the past three decades, the WHO or NCHS/WHO growth references have played an important role internationally in the assessment of child and adolescent growth and nutritional status. However, the references have a number of weaknesses. The limitations of the infant portion of the references were thoroughly assessed in WHO's effort to develop a new international growth reference for infants and preschool children. The present report discusses the limitations of the NCHS/WHO references for school-aged children and adolescents, including a number of conceptual, methodological, and practical problems. The global obesity epidemic poses another challenge that the NCHS/WHO reference cannot appropriately meet. There is a need for a single international reference to assess the nutritional status and growth of school-aged children and adolescents across different countries.

Dietary Risk Factors for Development of Childhood Obesity

Current Opinion in Clinical Nutrition and Metabolic Care. May, 2007  |  Pubmed ID: 17414504

Controversial information exists on the contribution of several dietary factors for overweight development in childhood, but there is no doubt that obesity prevalence is increasing. We review the most up-to-date information in order to clarify the evidence-based dietary aspects influencing obesity development in children and adolescents.

Cardiorespiratory Fitness and Sedentary Activities Are Associated with Adiposity in Adolescents

Obesity (Silver Spring, Md.). Jun, 2007  |  Pubmed ID: 17557997

To determine whether physical activity, sedentary activities, and/or cardiorespiratory fitness are related to waist circumference in adolescents, as previously reported in adults.

Physical Performance and School Physical Education in Overweight Spanish Children

Annals of Nutrition & Metabolism. 2007  |  Pubmed ID: 17627091

To evaluate the effect of physical performance and extracurricular organized physical activities (EOPA) in normal- and overweight children.

Adiposity, Physical Activity, and Physical Fitness Among Children from Aragón, Spain

Obesity (Silver Spring, Md.). Aug, 2007  |  Pubmed ID: 17712107

The main purpose of this study was to determine the relationship between physical activity (PA) levels and adiposity. The secondary purpose was to assess the effect of physical fitness and living area on adiposity.

Effect of the Ala12 Allele in the PPARgamma-2 Gene on the Relationship Between Birth Weight and Body Composition in Adolescents: the AVENA Study

Pediatric Research. Nov, 2007  |  Pubmed ID: 17805195

The intent of this study was to assess whether the effect of birth weight on later body composition is modified by Pro12Pro, Pro12Ala, and Ala12Ala genotypes of the peroxisome proliferator-activated receptor gamma-2 (PPARgamma-2) gene. The PPARgamma-2 gene polymorphism was genotyped in 273 adolescents aged 13-18.5 y, born at term and whose birth weight was known. They were selected from a cross-sectional multicenter study conducted in five Spanish cities in 2000-2002. Body mass index (BMI) was calculated from weight and height measurements, and body composition and fat distribution were estimated from skinfold thickness. A total of 229 subjects (111 males and 118 females) carried the Pro12Pro genotype and 44 (22 males and 22 females) the Pro12Ala and Ala12Ala PPARgamma-2 genotypes. In the Pro12Pro group, birth weight Z score was positively associated with both fat-free mass (FFM) (p < 0.05) and fat mass (FM) (p < 0.05), but these relationships disappeared after controlling for age, gestational age, socioeconomic status (SES), physical activity, Tanner stage, sex, and BMI. In the Ala12 group, birth weight Z score was positively associated with FFM (p < 0.01), and this relationship remained significant after controlling for confounding variables (p < 0.05). Small body weight at birth may program lower FFM in adolescents carrying the Ala12 allele in the PPARgamma-2 gene.

Lifestyle-related Determinants of Inflammation in Adolescence

The British Journal of Nutrition. Oct, 2007  |  Pubmed ID: 17922948

Inflammatory processes are involved in the pathogenesis of the most common chronic non-communicable diseases and may also play an important initiating role in their development. Only recently have inflammatory markers been included in epidemiological studies focusing on nutritional status, body composition and physical activity. We are just starting to understand how different lifestyles can determine basal levels of inflammatory biomarkers in early ages. This review aims to summarise what is known about the relationships between lifestyle-related determinants (focusing on overweight, physical activity and dietary habits) and inflammatory markers in apparently healthy young populations. Obesity is the most widely studied determinant. Several large-scale studies have now demonstrated that healthy young subjects with more body fat or higher BMI have moderately higher concentrations of inflammatory markers than their leaner peers, supporting the idea that obesity should be considered as a state of chronic low-grade inflammation. Less data is available to allow us to elucidate how physical activity/fitness or dietary patterns may have a direct effect on inflammation in apparently healthy, disease-free young populations.

Childhood Obesity: Every Little Bit Helps

Journal of Epidemiology and Community Health. Mar, 2007  |  Pubmed ID: 17325401

Sedentary Behaviour and Obesity Development in Children and Adolescents

Nutrition, Metabolism, and Cardiovascular Diseases : NMCD. Mar, 2008  |  Pubmed ID: 18083016

Sedentary lifestyle patterns in children and adolescents, i.e. playing digital games, using computers and especially watching television, have been associated with obesity. However, not all sedentary behaviour has shown the same relevance to, and relationship with, obesity. Therefore, we conducted a review including published studies found in PubMed and other medical journals, dated between January 1990 and April 2007. The ages of the children and adolescents who were the object of the study ranged between 2 and 18 years. For the purpose of this paper, we selected cross-sectional, longitudinal and intervention studies. Sufficient evidence exists to recommend setting a limit to the time spent watching TV, especially for younger children. However, video games and computers do not represent such a high risk compared to watching TV, when they do not replace physical activity too much. In fact, there is no evidence to suggest that sedentary behaviour displaces physical activity levels. Mechanisms that explain the link between sedentariness and obesity are also discussed. Finally, future studies should take into account important mediators such as socioeconomic status and family structure.

Inflammatory Proteins and Muscle Strength in Adolescents: the Avena Study

Archives of Pediatrics & Adolescent Medicine. May, 2008  |  Pubmed ID: 18458193

To examine the associations between inflammatory proteins and muscle strength and to determine whether this association varies between overweight and nonoverweight adolescents.

Small Birth Weight and Later Body Composition and Fat Distribution in Adolescents: the Avena Study

Obesity (Silver Spring, Md.). Jul, 2008  |  Pubmed ID: 18464751

To assess the association between birth weight and body composition and fat distribution in adolescents, and to test the possible sex-specific effect in these relationships.

Physical Fitness Effect on Bone Mass is Mediated by the Independent Association Between Lean Mass and Bone Mass Through Adolescence: a Cross-sectional Study

Journal of Bone and Mineral Metabolism. 2008  |  Pubmed ID: 18470671

We studied 278 adolescents (169 females) aged 13.0-18.5 years to elucidate whether an independent effect of physical fitness and lean mass in the differences between male and female bones can be detected. Lean and fat masses and bone mineral content (BMC) were measured with DXA. Physical fitness was evaluated with six different tests included in the EUROFIT test battery (flexibility, isometric, dynamic and endurance strength, speed, and cardiovascular fitness). To test the independent relationship between physical fitness and bone mass, multiple regression analysis was applied, including lean mass, age, and Tanner development as covariates. The males had a 43% lower fat mass and 40% and 16% higher lean mass and total BMC compared with the females (all P < 0.05). After adjustment for differences in body size and lean mass, the females exhibited a 7.4% higher BMC than the males (P < 0.05). The multiple regression analysis showed that lean mass had an independent relationship with bone mass (P < 0.001), explaining 67% of the total variance in whole-body BMC. In males, change in R (2) was 0.658 for hand grip and 0.035-0.151 for the rest of physical fitness-related variables; but 0.019-0.042 in females (all P-0.001); however, the independent relationships between physical fitness and bone disappeared after controlling for lean mass. In conclusion, it is likely the differences between male and female in bone mass could be explained by differences in lean mass and physical fitness.

Television Watching, Videogames, and Excess of Body Fat in Spanish Adolescents: the AVENA Study

Nutrition (Burbank, Los Angeles County, Calif.). Jul-Aug, 2008  |  Pubmed ID: 18472399

We assessed the individual association of sedentary behaviors with the risk of overweight and excess body fat (overfat) in adolescents.

Methylenetetrahydrofolate Reductase 677CT Polymorphism and Cobalamin, Folate, and Homocysteine Status in Spanish Adolescents

Annals of Nutrition & Metabolism. 2008  |  Pubmed ID: 18714149

Folate and cobalamin are responsible for healthy growth. However, the B-vitamin and homocysteine status of adolescents is not well known. The aim was to assess the status of folate, cobalamin, and homocysteine in healthy Spanish adolescents.

Birth Weight and Blood Lipid Levels in Spanish Adolescents: Influence of Selected APOE, APOC3 and PPARgamma2 Gene Polymorphisms. The AVENA Study

BMC Medical Genetics. 2008  |  Pubmed ID: 19000312

There is increasing evidence indicating that genes involved in certain metabolic processes of cardiovascular diseases may be of particular influence in people with low body weight at birth. We examined whether the apolipoprotein (APO) E, APOC3 and the peroxisome proliferator-activated receptor-gamma-2 (PPARgamma2) polymorphisms influence the association between low birth weight and blood lipid levels in healthy adolescents aged 13-18.5 years.

High Fitness is Associated with a Healthier Programming of Body Composition at Adolescence

American Journal of Human Biology : the Official Journal of the Human Biology Council. Nov-Dec, 2008  |  Pubmed ID: 18770529

The programming effect of birth weight on later body composition has become of increasing interest in recent years. This programming effect is affected by factors such as gender. Physical fitness could be another factor of influence. This study aimed to examine whether handgrip strength (HG) or cardiovascular fitness (CVF) modify the associations between birth weight and body composition in adolescents. A sample of 1,740 (942 females) adolescents aged 13 to 18.5 years, born at more than 35 weeks of gestation, from the AVENA study was studied. Waist circumference was measured, percentage body fat was calculated from skinfold thicknesses and fat free mass was derived by subtracting fat mass from total body weight. HG and CVF were assessed using the HG test and the 20 m shuttle run test, respectively. Birth weight was positively associated with fat free mass in females with high (above the median) CVF (P < 0.001), but not in those with low (below the median) CVF. In contrast, birth weight was positively associated with total and central adiposity in males with low HG (both P = 0.002), but not in those with high HG. These results suggest that the programming effect of birth weight on later body composition is dependent on gender and fitness level. A high birth weight may have a healthy programming effect on body composition in those adolescents with a high fitness level, being associated with increased fat free mass levels in females and not showing the increased adiposity levels observed in unfit males.

Are Muscular and Cardiovascular Fitness Partially Programmed at Birth? Role of Body Composition

The Journal of Pediatrics. Jan, 2009  |  Pubmed ID: 18783796

To determine whether birth weight is associated with handgrip strength and cardiovascular fitness in adolescence and, if so, how these associations are influenced by current body composition.

Associations Between Common Genetic Polymorphisms in Angiopoietin-like Proteins 3 and 4 and Lipid Metabolism and Adiposity in European Adolescents and Adults

The Journal of Clinical Endocrinology and Metabolism. Dec, 2009  |  Pubmed ID: 19890028

Plasma-borne angiopoietin-like proteins (ANGPTL) act as endocrine factors on their target tissues. Because ANGPTL3 and ANGPTL4 play important roles in lipid metabolism and the regulation of adiposity in mice, we hypothesized that genetic variability at the ANGPTL3 and ANGPTL4 genes loci might influence lipid metabolism and fat deposition in humans.

Design and Evaluation of a Treatment Programme for Spanish Adolescents with Overweight and Obesity. The EVASYON Study

BMC Public Health. 2009  |  Pubmed ID: 19912668

The prevalence of overweight and obesity (OW/OB) among adolescents worldwide has increased since the 60 s. Spain has reached one of the highest OW/OB prevalence rates among adolescents from European countries. The aim of this methodological paper is to describe the design and evaluation in the EVASYON study (Development, implementation and evaluation of the efficacy of a therapeutic programme for adolescents with OW/OB: integral education on nutrition and physical activity).

Truncal and Abdominal Fat As Determinants of High Triglycerides and Low HDL-cholesterol in Adolescents

Obesity (Silver Spring, Md.). May, 2009  |  Pubmed ID: 19180070

We examined whether abdominal and truncal adiposity, assessed with simple anthropometric indices, determines serum triglycerides and high-density lipoprotein (HDL)-cholesterol levels independently of total adiposity amount in adolescents. A total of 547 Spanish adolescents (284 males and 263 females) aged 13-18.5 years were included in this study. Measures of truncal adiposity included subscapular to triceps ratio, and trunk-to-total skinfolds ratio (TTS%). Waist circumference was used as a surrogate of abdominal adiposity, and BMI was used as a measure of total adiposity. The results of the regression models indicated that levels of triglycerides were positively associated with waist circumference and TTS% after controlling for age and Tanner stage in both sexes. Once BMI was entered in the model, these associations remained significant for waist circumference in females. HDL-cholesterol levels were negatively associated with waist circumference in both sexes, and with subscapular to triceps ratio and TTS% in males, after controlling for age and Tanner stage. Once BMI was entered in the model, these associations remained significant for subscapular to triceps ratio and for TTS% in males. The results of this study suggest that in male adolescents, truncal adiposity is negatively associated with levels of HDL-cholesterol, whereas in females, abdominal adiposity is positively associated with levels of triglycerides independently of total adiposity. These findings highlight the deleterious effect of both truncal and abdominal fat depots on the lipid profile already from the first decades of life.

Body Fat Measurement in Elite Sport Climbers: Comparison of Skinfold Thickness Equations with Dual Energy X-ray Absorptiometry

Journal of Sports Sciences. Mar, 2009  |  Pubmed ID: 19204847

The aim of this study was to compare equations for estimating percentage body fat from skinfold thickness in elite sport climbers by assessing their agreement with percentage body fat measured using dual-energy X-ray absorptiometry (DXA). Skinfold thickness was measured in a convenience sample of 19 elite sport climbers [9 women and 10 men; mean age 31.2 years (s = 5.0) and 28.6 years (s = 3.6), respectively]. Percentage body fat was estimated using 17 different equations, and it was also measured by DXA. A significant inter-methods difference was observed for all equations, except for Durnin's equation in men (inter-methods difference: -0.57% and -0.29%; 1.96 s: 5.56 and 5.23 for Siri's and Brozek's equation, respectively) and women (inter-methods difference: -0.67% and -1.29% for Siri's and Brozek's equation, respectively), and for Wilmore's equation using Siri's body fat equation in women (inter-methods difference: -1.86%). In women, the limits of agreement were lower when using Durnin's equation compared with Wilmore's equation (1.96 s: 3.86% and 5.13%, respectively). In conclusion, of the 17 studied equations, Durnin's equation was the most accurate in estimating percentage body fat in both male and female elite climbers. Therefore, Durnin's equation could be used to assess percentage body fat in elite sport climbers if more accurate methods are not available. The generalizability of the results is limited by the fact that the sample was not selected at random.

Interplay Between Weight Loss and Gut Microbiota Composition in Overweight Adolescents

Obesity (Silver Spring, Md.). Oct, 2009  |  Pubmed ID: 19390523

The aim of this study was to determine the influence of an obesity treatment program on the gut microbiota and body weight of overweight adolescents. Thirty-six adolescents (13-15 years), classified as overweight according to the International Obesity Task Force BMI criteria, were submitted to a calorie-restricted diet (10-40%) and increased physical activity (15-23 kcal/kg body weight/week) program over 10 weeks. Gut bacterial groups were analyzed by quantitative real-time PCR before and after the intervention. A group of subjects (n=23) experienced >4.0 kg weight loss and showed significant BMI (P=0.030) and BMI z-score (P=0.035) reductions after the intervention, while the other group (n=13) showed <2.0 kg weight loss. No significant differences in dietary intake were found between both groups. In the whole adolescent population, the intervention led to increased Bacteroides fragilis group (P=0.001) and Lactobacillus group (P=0.030) counts, and to decreased Clostridium coccoides group (P=0.028), Bifidobacterium longum (P=0.031), and Bifidobacterium adolescentis (P=0.044) counts. In the high weight-loss group, B. fragilis group and Lactobacillus group counts also increased (P=0.001 and P=0.007, respectively), whereas C. coccoides group and B. longum counts decreased (P=0.001 and P=0.044, respectively) after the intervention. Total bacteria, B. fragilis group and Clostridium leptum group, and Bifidobacterium catenulatum group counts were significantly higher (P<0.001-0.036) while levels of C. coccoides group, Lactobacillus group, Bifidobacterium, Bifidobacterium breve, and Bifidobacterium bifidum were significantly lower (P<0.001-0.008) in the high weight-loss group than in the low weight-loss group before and after the intervention. These findings indicate that calorie restriction and physical activity have an impact on gut microbiota composition related to body weight loss, which also seem to be influenced by the individual's microbiota.

Breast-feeding: A Commentary by the ESPGHAN Committee on Nutrition

Journal of Pediatric Gastroenterology and Nutrition. Jul, 2009  |  Pubmed ID: 19502997

This medical position article by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition summarises the current status of breast-feeding practice, the present knowledge on the composition of human milk, advisable duration of exclusive and partial breast-feeding, growth of the breast-fed infant, health benefits associated with breast-feeding, nutritional supplementation for breast-fed infants, and contraindications to breast-feeding. This article emphasises the important role of paediatricians in the implementation of health policies devised to promote breast-feeding.The European Society for Paediatric Gastroenterology, Hepatology, and Nutrition Committee on Nutrition recognises breast-feeding as the natural and advisable way of supporting the healthy growth and development of young children. This article delineates the health benefits of breast-feeding, reduced risk of infectious diarrhoea and acute otitis media being the best documented. Exclusive breast-feeding for around 6 months is a desirable goal, but partial breast-feeding as well as breast-feeding for shorter periods of time are also valuable. Continuation of breast-feeding after the introduction of complementary feeding is encouraged as long as mutually desired by mother and child.The role of health care workers, including paediatricians, is to protect, promote, and support breast-feeding. Health care workers should be trained in breast-feeding issues and counselling, and they should encourage practices that do not undermine breast-feeding. Societal standards and legal regulations that facilitate breast-feeding should be promoted, such as providing maternity leave for at least 6 months and protecting working mothers.

Early Life Programming of Abdominal Adiposity in Adolescents: The HELENA Study

Diabetes Care. Nov, 2009  |  Pubmed ID: 19641158

To examine the relationship between birth weight and abdominal adiposity in adolescents.

Haematological Reference Values in Spanish Adolescents: the AVENA Study

European Journal of Haematology. Dec, 2009  |  Pubmed ID: 19659559

To provide reference values for haematological indices in Spanish adolescents according to age and gender.

The Effect of Early Menarche on Later Body Composition and Fat Distribution in Female Adolescents: Role of Birth Weight

Annals of Nutrition & Metabolism. 2009  |  Pubmed ID: 19786740

To examine the effect of early menarche (EM) on adolescent body composition and fat distribution, and to explore the possible contribution of birth weight (BW) to this relationship.

Assessment of the Medial Longitudinal Arch in Children and Adolescents with Obesity: Footprints and Radiographic Study

European Journal of Pediatrics. May, 2009  |  Pubmed ID: 18751725

The purpose of this study was to evaluate foot arch types of obese children and adolescents aged 9-16.5 years using both indirect and direct measures. Fifty-eight obese children/adolescents attending the paediatric endocrinology unit of the University Hospital "Lozano Blesa" in Zaragoza were selected as experimental subjects. Fifty-eight gender and age matched, normal-weight children/adolescents were selected as control subjects. To assess the medial longitudinal arch (MLA) height, which is used as a main reference for the diagnosis of flatfoot, footprints from both feet were collected (in both groups) and lateral weight-bearing radiographs of both feet were taken (of 49 of the 58 obese children). Footprint angle (FA) and the Chippaux-Smirak index (CSI) were calculated from the footprints. Talus-first metatarsal (TFMA) and calcaneal inclination angles (CIA) were obtained from lateral feet radiographs. In the normal-weight group, mean values of FA and CSI indicated a normal MLA. In the obese group, morphological flatfoot was identified. Comparison between both groups, by side and gender, showed a decrease of FA (p<0.001) and an increase of CSI (p<0.001) in obese subjects. Mean values of TFMA and CIA in the obese group indicated a lowering of the MLA. Obese children/adolescents between 9 and 16.5 years of age had significantly lower values of FA and higher CSI, related to a lower MLA. Radiographic parameters supported these findings and mean values were associated with a fall of this arch.

Maximizing Bone Mineral Mass Gain During Growth for the Prevention of Fractures in the Adolescents and the Elderly

Bone. Feb, 2010  |  Pubmed ID: 19840876

Bone mass is a key determinant of fracture risk. Maximizing bone mineral mass during childhood and adolescence may contribute to fracture risk reduction during adolescence and possibly in the elderly. Although more than 60% of the variance of peak bone mass (PBM), the amount of bone present in the skeleton at the end of its maturation process, is genetically determined, the remainder is likely influenced by factors amenable to positive intervention, such as adequate dietary intake of dairy products as a natural source of calcium and proteins, vitamin D, and regular weight-bearing physical activity. Low calcium and vitamin D intakes are associated with negative effects on bone, including suboptimal PBM acquisition. As suggested by intervention studies, regular intake of dairy products may have positive and possibly sustained effects on bone mineral mass gain, contributing thereby to fracture risk reduction. Further evidence from intervention studies suggests that weight-bearing physical activities, such as jumping, may contribute to bone mineral mass gain in children. Optimizing PBM acquisition through dietary and physical exercise measures may represent a valuable primary method for the prevention of fractures.

Breast-feeding Modulates the Influence of the Peroxisome Proliferator-activated Receptor-gamma (PPARG2) Pro12Ala Polymorphism on Adiposity in Adolescents: The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Cross-sectional Study

Diabetes Care. Jan, 2010  |  Pubmed ID: 19846795

The peroxisome proliferator-activated receptor-gamma2 (PPARG2) Pro12Ala polymorphism has been associated with a higher BMI and a lower risk of type 2 diabetes in adulthood. The association between adiposity and PPARG variants can be influenced by environmental factors such as early growth, dietary fat, and (as recently shown) breast-feeding. The objectives of this study were to assess 1) the influence of the PPARG2 Pro12Ala polymorphism on adiposity markers in adolescents and 2) a possible modulating effect of breast-feeding on these associations.

Effects of Diet on Growth of Children with Obesity

Journal of Pediatric Gastroenterology and Nutrition. Dec, 2010  |  Pubmed ID: 21088542

Trends of Dietary Habits in Adolescents

Critical Reviews in Food Science and Nutrition. Feb, 2010  |  Pubmed ID: 20112152

Lifestyle plays an important role in the development of obesity during childhood and adolescence. We provide up-to-date information about the relationship between obesity and food intake and dietary patterns in adolescents. Scientific evidence is increasing about the dietary factors associated with this relationship, specifically a low meal frequency, skipping breakfast, and a high consumption of sugar sweetened beverages. Maybe some of the reviewed dietary factors could cluster in the same population of adolescents, increasing the individual risk. There is little information about dietary patterns and current time trends in adolescents; however, the available data seem to show that the tendency in the adolescent population worldwide is to increase those dietary factors related with obesity development. Public health efforts should be emphasized in order to decrease the current tendency. Regular family meals could serve as role models for healthy eating behaviors. Educational intervention programs for parents, aiming to modify the healthfulness of the diet, seems to be one of the most adequate tools to deal with the worldwide obesity epidemic.

Individual and Combined Effects of ApoE and MTHFR 677C/T Polymorphisms on Cognitive Performance in Spanish Adolescents: the AVENA Study

The Journal of Pediatrics. Jun, 2010  |  Pubmed ID: 20223480

To examine the individual and combined associations of ApoE and MTHFR 677C/T polymorphisms with cognitive performance in adolescents.

Influence of Socioeconomic Factors on Fitness and Fatness in Spanish Adolescents: the AVENA Study

International Journal of Pediatric Obesity : IJPO : an Official Journal of the International Association for the Study of Obesity. Dec, 2010  |  Pubmed ID: 20233152

This study was to examine the influence of socioeconomic status on fitness and fatness in Spanish adolescents.

Extra-curricular Participation in Sports and Socio-demographic Factors in Spanish Adolescents: the AVENA Study

Journal of Sports Sciences. Nov, 2010  |  Pubmed ID: 20981609

The aims of this study were to identify differences between the sexes in extra-curricular participation in sports and to determine its association with body fat and socio-demographic factors in Spanish adolescents. A total of 2165 adolescents (1124 males and 1041 females) aged 13.0-18.5 years from the AVENA Study participated. Participants filled in an ad hoc questionnaire for extra-curricular participation in sports, which was the dependent variable. Independent variables were: age, percent body fat, and father's and mother's educational level and occupation. Chi-square tests and logistic regression were applied. Bivariate analysis showed for male adolescents that age and father's occupation were related to extra-curricular participation in sports. In addition, body fat and mother's education and occupation (all P < 0.05) were related to extra-curricular participation of in sports for female adolescents. Logistic regression analysis showed that the likelihood of involvement in extra-curricular participation in sports was 5.3-fold (3.86-7.38) higher for males than females. Age and father's education in both males and females were independently associated with extra-curricular participation in sports. In summary, Spanish male adolescents were shown to engage in more extra-curricular sports than females. In addition, age and father's education (in both sexes) were associated with the participation of their offspring in extra-curricular sports during adolescence.

Single-nucleotide Polymorphism of CD36 Locus and Obesity in European Adolescents

Obesity (Silver Spring, Md.). Jul, 2010  |  Pubmed ID: 19893500

CD36 is a membrane receptor with a wide variety of functions, including the regulation of energy metabolism, fat storage, and adipocyte differentiation. To assess the relationship between CD36 gene single-nucleotide polymorphisms (SNPs) and obesity in adolescents, we evaluated the relationship between CD36 SNPs and the risk of obesity in a case-control study composed of 307 obese (age = 15.0 +/- 1.1 years) and 339 normal-weight adolescents (age = 14.6 +/- 1.1 years). To validate the results, we assessed the relation between the same SNPs and percentage of body fat (BF%) and BMI in 1,151 European adolescents (age = 14.8 +/- 1.4 years). SNPs with a minor allele frequency >0.10 were selected to tag CD36. Genotyping was performed on an Illumina system. Four SNPs (rs3211867, rs3211883, rs3211908, and rs1527483) were associated with increased risk of obesity in the case-control study (odds ratio (OR) (95% confidence interval)): 1.96 (1.26-3.04], P = 0.003; 1.73 (1.16-2.59), P = 0.007; 2.42 (1.47-4.01), P = 0.0005 and 1.95 (1.25-3.05), P = 0.003, respectively). The same four SNPs were associated with higher BMI (P < 0.05) and BF% (P < 0.04) in the validation study. Further analyses identified a haplotype (frequency: 0.05) carrying the minor allele of these SNPs as being associated with obesity (OR: 2.28; P = 0.0008) in the case-control study and with excess adiposity (i.e., higher BF% (P = 0.03) and BMI (P = 0.04)) in the validation study. Our data suggest that genetic variability at the CD36 gene locus could be associated with body weight variability in European adolescents but these findings require replication.

Sedentary Patterns and Media Availability in European Adolescents: The HELENA Study

Preventive Medicine. Jul, 2010  |  Pubmed ID: 20359491

To describe sedentary behaviors in adolescents and to examine the influence of media availability on TV viewing.

Attenuation of the Effect of the FTO Rs9939609 Polymorphism on Total and Central Body Fat by Physical Activity in Adolescents: the HELENA Study

Archives of Pediatrics & Adolescent Medicine. Apr, 2010  |  Pubmed ID: 20368485

To examine whether physical activity attenuates the effect of the FTO rs9939609 polymorphism on body fat estimates in adolescents.

Association of Physical Activity with Muscular Strength and Fat-free Mass in Adolescents: the HELENA Study

European Journal of Applied Physiology. Aug, 2010  |  Pubmed ID: 20373108

The objective of this study is to analyse the association of objectively assessed physical activity (PA) with muscular strength and fat-free mass in adolescents, and to determine whether meeting the current PA recommendations is associated with higher levels of muscular strength and fat-free mass. The present cross-sectional study comprised 363 Spanish adolescents (180 females) aged 12.5-17.5 years. PA was assessed by accelerometry and expressed as average PA (counts/min), and min/day of inactive, light, moderate, vigorous and moderate to vigorous PA (MVPA). MVPA was dichotomized into < 60 min/day and > or = 60. Upper body muscular strength was measured with the handgrip strength test, and lower body muscular strength was measured with the standing broad jump, squat jump, counter movement jump and Abalakov tests. Fat-free mass was measured by DXA. We observed positive associations between vigorous PA and all the lower body muscular strength tests except for the counter movement jump in males. PA was not associated with fat-free mass in both males and females. Male adolescents engaged in at least 60 min/day MVPA performed better in the standing broad jump test. In conclusion, the findings of the present study suggest that only vigorous PA is associated with muscular strength, particularly lower-body muscular strength in male adolescents.

Evaluation of a Computer-tailored Physical Activity Intervention in Adolescents in Six European Countries: the Activ-O-Meter in the HELENA Intervention Study

The Journal of Adolescent Health : Official Publication of the Society for Adolescent Medicine. May, 2010  |  Pubmed ID: 20413082

The present study investigates the effect of the Activ-O-Meter, an internet-based computer-tailored physical activity intervention in adolescents in six European centers involved in the HELENA study.

Single Nucleotide Polymorphisms in the FADS Gene Cluster Are Associated with Delta-5 and Delta-6 Desaturase Activities Estimated by Serum Fatty Acid Ratios

Journal of Lipid Research. Aug, 2010  |  Pubmed ID: 20427696

Genetic variability in the FADS1-FADS2 gene cluster [encoding delta-5 (D5D) and delta-6 (D6D) desaturases] has been associated with plasma long-chain PUFA (LCPUFA) and lipid levels in adults. To better understand these relationships, we further characterized the association between FADS1-FADS2 genetic variability and D5D and D6D activities in adolescents. Thirteen single nucleotide polymorphisms (SNPs) were genotyped in 1,144 European adolescents (mean +/- SD age: 14.7 +/- 1.4 y). Serum phospholipid fatty acid levels were analyzed using gas chromatography. D5D and D6D activities were estimated from the C20:4n-6/C20:3n-6 and C20:3n-6/C18:2n-6 ratios, respectively. Minor alleles of nine SNPs were associated with higher 18:2n-6 levels (1.9E-18

No Association Between Polymorphisms in the INSIG1 Gene and the Risk of Type 2 Diabetes and Related Traits

The American Journal of Clinical Nutrition. Jul, 2010  |  Pubmed ID: 20444954

The insulin-induced gene 1 (INSIG1) encodes a protein that blocks proteolytic activation of sterol regulatory element binding proteins, which are transcription factors that activate genes that regulate cholesterol, fatty acid, and glucose metabolism.

Excessive TV Viewing and Cardiovascular Disease Risk Factors in Adolescents. The AVENA Cross-sectional Study

BMC Public Health. 2010  |  Pubmed ID: 20500845

Excessive television (TV) viewing might play an important role in the development of cardiovascular disease (CVD). The aim of this study was to examine the independent associations between TV viewing and CVD risk factors in adolescents.

Sleep Patterns in Spanish Adolescents: Associations with TV Watching and Leisure-time Physical Activity

European Journal of Applied Physiology. Oct, 2010  |  Pubmed ID: 20556419

We aimed to describe the sleep patterns in Spanish adolescents and to examine the relationships of sleep duration and morning tiredness with participation in leisure-time physical-sporting activities (LT-PA) and television (TV) watching. Sleep duration, morning tiredness, participation in LT-PA and time spent on watching TV were reported by 2,179 (1,139 females) Spanish adolescents (AVENA study). Data were analyzed by binary logistic regression. One-fifth of the adolescents reported insufficient night sleep (<8 h) on school days. The review of the literature (30 studies) showed that the Spanish adolescents sleep as long as adolescents from central Europe, and longer than those from other Mediterranean countries, South Africa, Asia and North America. Insufficient sleep duration doubled the odds of excessive TV watching (≥3 h/day) in males, regardless of morning tiredness (OR 2.15, 95% CI 1.42-3.27). Morning tiredness reduced the odds of participating in any LT-PA in both males and females (0.49, 0.34-0.70 and 0.49, 0.35-0.69, respectively), and increased the odds of excessive TV watching in females, regardless of sleep duration (2.49, 1.64-3.79). We conclude that non-participation in LT-PA is associated with morning tiredness in male and female adolescents, while excessive TV watching is more associated with short sleep or morning tiredness depending on gender.

Passive Smoking Alters Circulating Naïve/memory Lymphocyte T-cell Subpopulations in Children

Pediatric Allergy and Immunology : Official Publication of the European Society of Pediatric Allergy and Immunology. Dec, 2010  |  Pubmed ID: 20561234

While it has been indicated that exposure to second-hand smoke (SHS) can cause a local in vivo response, limited evidence exists on its possible systemic effects from population-based levels of exposure. We investigated into a possible systemic response in the immune parameters and lymphocyte subsets, i.e. B cell (CD19+), T cell (CD4+CD45RO+, CD4+CD45RA+, CD3+CD45RO+, CD3+CD45RA+) and natural killer (CD3+CD16CD56+) lymphocyte subsets relative to exposure to SHS. Blood was drawn from healthy, verified non-smoker, adolescent subjects (n = 68, mean age 14.2) and analysed for cotinine, antioxidants and lymphocyte immunophenotyping. SHS exposure was assessed using serum cotinine. Biomarker quantified exposure to SHS was correlated with a linear dose-response reduction in the percentages of memory CD4+CD45RO+ (p = 0.005) and CD3+CD45RO+ T-cell subsets (p = 0.005 and p = 0.003, respectively) and a linear increase in the percentage of naïve CD4+CD45RA+ and CD3+CD45RA+ T-cell subsets (p = 0.006 and p = 0.003, respectively). Additionally, higher exposure to SHS was associated with a higher CD4+CD45RA+ count (532 vs. 409 cells/ml, p = 0.017). Moreover, after controlling for age, gender, body mass index and plasma antioxidants, SHS exposure was found to be associated with the percentage of circulating naïve and memory CD4+ and CD3+ T-cell subpopulations, as revealed through a linear regression analysis. These findings indicate a systemic immunological response in healthy adolescents exposed to population-based levels of SHS exposure and imply an additional biological pathway for the interaction between exposure to SHS and its adverse effects on human health.

Physical Activity, Fitness, Weight Status, and Cognitive Performance in Adolescents

The Journal of Pediatrics. Dec, 2010  |  Pubmed ID: 20673915

To examine the association of participation in physical sports activity during leisure time, sedentary behaviors, cardiorespiratory and muscular fitness, and weight status with cognitive performance in Spanish adolescents.

Recommended Levels of Physical Activity to Avoid an Excess of Body Fat in European Adolescents: the HELENA Study

American Journal of Preventive Medicine. Sep, 2010  |  Pubmed ID: 20709251

It is unclear how much physical activity is necessary to prevent obesity during adolescence.

Recommended Levels and Intensities of Physical Activity to Avoid Low-cardiorespiratory Fitness in European Adolescents: The HELENA Study

American Journal of Human Biology : the Official Journal of the Human Biology Council. Nov-Dec, 2010  |  Pubmed ID: 20721983

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).

Longer Breastfeeding is Associated with Increased Lower Body Explosive Strength During Adolescence

The Journal of Nutrition. Nov, 2010  |  Pubmed ID: 20861216

Our aim in this study was to examine the association between breastfeeding duration and cardiorespiratory fitness, isometric strength, and explosive strength during adolescence. A total of 2567 adolescents (1426 girls) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study aged 12.5-17.5 y were included. Information about duration of any and exclusive breastfeeding was obtained retrospectively by means of a parental questionnaire. The 20-m shuttle run, handgrip strength, and standing long jump tests were used to assess physical fitness. Significant differences among the categories of breastfeeding duration were tested using ANCOVA after adjusting for a set of potential confounders: gestational and current age, birth weight, sexual maturation, fat mass, fat-free mass, maternal education, parental weight status, country, smoking behavior, and days of vigorous physical activity. Longer breastfeeding (either any or exclusive) was associated with a higher performance in the standing long jump test in both boys and girls (P < 0.001), regardless of fat mass, fat-free mass, and the rest of potential confounders. In adolescents who were breastfed for 3-5 mo or ≥6 mo, the risk of having a standing long jump performance below the 5th percentile was reduced by half compared with those who were never breastfed [odds ratio (OR) = 0.54, 95% CI = 0.30-0.96, P < 0.05; and OR = 0.40, 95% CI = 0.22-0.74, P < 0.01, respectively). These findings suggest a role of breastfeeding in determining lower body explosive strength during adolescence.

Common Polymorphisms in Six Genes of the Methyl Group Metabolism Pathway and Obesity in European Adolescents

International Journal of Pediatric Obesity : IJPO : an Official Journal of the International Association for the Study of Obesity. Jun, 2011  |  Pubmed ID: 20883119

The goal of the present study was to assess the relationship between the genetic variability in six genes of methyl group (CH(3)) metabolism and the risk of obesity.

Adolescent's Physical Activity Levels and Relatives' Physical Activity Engagement and Encouragement: the HELENA Study

European Journal of Public Health. Dec, 2011  |  Pubmed ID: 20935036

The aim of this article is to examine the association between adolescents' physical activity (PA) levels and their relatives' (father, mother, brothers, sisters and best friend) PA engagement and encouragement.

Contribution of Bone Turnover Markers to Bone Mass in Pubertal Boys and Girls

Journal of Pediatric Endocrinology & Metabolism : JPEM. 2011  |  Pubmed ID: 22308850

The association between bone turnover markers and bone mass in adolescence is not clear. We aimed to evaluate the associations between bone turnover markers and bone mineral content (BMC), density (BMD) and area (BMA).

Comparison of Several Anthropometric Indices with Insulin Resistance Proxy Measures Among European Adolescents: The Helena Study

European Journal of Pediatrics. Jun, 2011  |  Pubmed ID: 21052739

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.

European Adolescents' Level of Perceived Stress and Its Relationship with Body Adiposity--The HELENA Study

European Journal of Public Health. Sep, 2011  |  Pubmed ID: 21908860

BACKGROUND: Since stress is hypothesized to be involved in the aetiology of obesity, the present study examined the current perception of stress in European adolescents and the association between adolescent perceived stress and their adiposity. METHODS: Observational data from 1121 adolescents aged 12.5-17.5 years from six European cities involved in the Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional study, was investigated. The adolescents completed the adolescent stress questionnaire, comprising 10 different stress dimensions. Anthropometric measurements (weight, height, skinfold thicknesses and circumferences) and bioelectrical impedance analysis were performed, and personal characteristics (age, pubertal stage and parental education) were collected. The measures of perceived stress were described for boys and girls separately and gender differences were investigated. Associations between the adolescents' perceived stress and indicators of general (body mass index z-score, sum of skinfold thicknesses and body fat%) and abdominal (waist and hip circumference, and waist/height ratio) adiposity were examined using hierarchical linear models. RESULTS: While girls reported systematically higher levels of stress compared with boys, their stress profiles were similar, with highest levels for school-related stress followed by future uncertainty. Only in girls, perceived stress was significantly associated with increased measures of general and abdominal adiposity. In boys, no relationship between perceived stress and adiposity measures was observed. CONCLUSIONS: School is reported to be an important source of adolescent stress and should be the focus of stress management campaigns. Only in girls, the hypothesis that stress might be involved in the aetiology of obesity during adolescence was supported.

Body Size at Birth Modifies the Effect of Fat Mass and Obesity Associated (FTO) Rs9939609 Polymorphism on Adiposity in Adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study

The British Journal of Nutrition. Sep, 2011  |  Pubmed ID: 21917193

The present study was intended to examine whether ponderal index (PI) at birth modifies the effect of the fat mass and obesity associated (FTO) rs9939609 polymorphism on adiposity in European adolescents. A total of 628 adolescents aged 14·4 (se 1·3) years (56·8 % female) were recruited. PI was calculated from parental reports of birth weight and length (kg/m3), and the BMI (kg/m2), body fat percentage and fat mass index (FMI, kg/m2) were calculated. The rs9939609 polymorphism was genotyped and physical activity assessed by accelerometry. Sex, duration of pregnancy, pubertal status, centre and physical activity were used as confounders in all the analyses. The minor A allele of the FTO rs9939609 was significantly associated with higher BMI, body fat percentage and FMI (all P < 0·05) but not with PI. Significant interactions between PI and the rs9939609 polymorphism in terms of body fat percentage (P = 0·002) and FMI (P = 0·017) were detected. However, this polymorphism was only significantly associated with higher BMI, body fat percentage and FMI (all P < 0·05) in adolescents in the lower PI tertile. Indeed, both body fat percentage and FMI were higher in those adolescents in the lower PI tertile carrying the A allele of the FTO rs9939609 polymorphism than in those with the TT genotype (25·0 (se 0·8) v. 22·1 (se 1·0) %, adjusted P = 0·030 and 5·6 (se 0·3) v. 4·6 (se 0·4) kg/m2, P = 0·031, respectively). Our findings suggest that those adolescents born with lower PI could be more vulnerable to the influence of the A risk allele of the FTO polymorphism on total adiposity content.

Self-reported Physical Activity in European Adolescents: Results from the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Public Health Nutrition. Feb, 2011  |  Pubmed ID: 20236565

To describe self-reported physical activity (PA) patterns in the various domains (school, home, transport, leisure time) and intensity categories (walking, moderate PA, vigorous PA) in European adolescents. Furthermore, self-reported PA patterns were evaluated in relation to gender, age category, weight status category and socio-economic status (SES).

Sedentary Behaviours and Socio-economic Status in Spanish Adolescents: the AVENA Study

European Journal of Public Health. Apr, 2011  |  Pubmed ID: 20304869

This study aimed to describe the influence of socio-economic status (SES) on the prevalence sedentary behaviours among Spanish adolescents.

European Adolescents' Level of Perceived Stress is Inversely Related to Their Diet Quality: the Healthy Lifestyle in Europe by Nutrition in Adolescence Study

The British Journal of Nutrition. Nov, 2011  |  Pubmed ID: 22054044

As stress is hypothesised to influence dietary behaviour, the relationship between perceived stress and diet quality in European adolescents was investigated. Within the Healthy Lifestyle in Europe by Nutrition in Adolescence study, adolescents (n 704, aged 12-17 years) from schools in five European cities (Ghent, Stockholm, Zaragoza, Athens and Vienna) completed a 2 d 24 h dietary recall assessment and an Adolescent Stress Questionnaire. Measurements and information were taken on height, weight, pubertal stage, parental education level, the level of moderate-to-vigorous physical activity (MVPA) and sleep duration. The Diet Quality Index for Adolescents (DQI-A) was calculated from the dietary data, which comprised three components reflecting dietary diversity, quality and equilibrium. Hierarchical linear models were performed to investigate the relationship between the adolescents' level of perceived stress and the DQI-A and its components, adjusting for relevant covariates (age, BMI z-score, pubertal stage and parental education). These models were additionally adjusted for MVPA or sleep duration. In both boys and girls, perceived stress was a significant independent negative predictor for their overall DQI-A. This inverse relationship was observed for all dietary components, except for dietary diversity in boys, and it was unaltered when additionally adjusted for MVPA or sleep duration. The observed inverse relationship between stress and diet quality within these European adolescents supports the hypothesis that stress influences dietary behaviour, thus emphasising the need for preventive stress-coping strategies for adolescents.

Physical Activity, Fitness, and Serum Leptin Concentrations in Adolescents

The Journal of Pediatrics. Nov, 2011  |  Pubmed ID: 22082954

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.

What Do Parents Think About Parental Participation in School-based Interventions on Energy Balance-related Behaviours? a Qualitative Study in 4 Countries

BMC Public Health. 2011  |  Pubmed ID: 22112159

Overweight and obesity in youth has increased dramatically. Therefore, overweight prevention initiatives should start early in life and target modifiable energy balance-related behaviours. Parental participation is often advocated as important for school-based interventions, however, getting parents involved in school-based interventions appears to be challenging based on earlier intervention experiences. The purpose of this study was to get insight into the determinants of and perspectives on parental participation in school-interventions on energy balance-related behaviours (physical activity, healthy eating, sedentary behaviours) in parents of ten- to twelve-year olds in order to develop an effective parental module for school-based interventions concerning energy balance-related behaviours.

Health Effects Related to Low Vitamin D Concentrations: Beyond Bone Metabolism

Annals of Nutrition & Metabolism. 2011  |  Pubmed ID: 22123633

Vitamin D is essential for a vast number of physiologic processes, and thus adequate levels are necessary or advantageous for optimal health. During childhood and adolescence, an adequate vitamin D status is needed due to its important role in cell growth, skeletal structure, and development.

Antioxidant Vitamin Status (A, E, C, and Beta-carotene) in European Adolescents - the HELENA Study

International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift Für Vitamin- Und Ernährungsforschung. Journal International De Vitaminologie Et De Nutrition. Jul, 2011  |  Pubmed ID: 22237774

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.

Objectively-measured and Self-reported Physical Activity and Fitness in Relation to Inflammatory Markers in European Adolescents: The HELENA Study

Atherosclerosis. Dec, 2011  |  Pubmed ID: 22265274

OBJECTIVE: Atherogenesis involves an inflammatory process that occurs early in life even though clinical symptoms are not observed until adulthood. Two important protective factors for low-grade inflammation may be physical activity (PA) and fitness. We examined the independent associations of objective and subjective measurements of PA and fitness with low-grade inflammation in European adolescents. METHODS: A total of 1045 adolescents, aged from 12.5 to 17.5 years old from 10 European cities, were selected from the HELENA-Cross-Sectional Study. Objectively-measured and self-reported PA variables were obtained by accelerometry and the International PA Questionnaire for Adolescents, respectively. Overall, cardiorespiratory, muscular and motor fitness variables were assessed by standardized field-based fitness tests and the International Fitness Scale. C-reactive protein (CRP), complement factors 3 (C3) and 4 (C4), interleukin-6 and TNF-α inflammatory markers were measured. RESULTS: Objectively-measured vigorous PA was inversely associated with C3 (β=-0.094, P=0.021) but it did not remain significant after any objective fitness indicator was included in the model. Other objectively measured or self-reported assessments of PA were not significantly associated with inflammatory markers. All objective measures of fitness were inversely associated with CRP, C3 and C4, whereas only self-reported motor fitness remained significantly associated with C3, C4 and TNF-α. All these observations were independent of age, sex, city and body mass index or waist circumference. CONCLUSION: High PA in adolescence may play an indirect role on lessening low-grade inflammation through improvements in fitness.

Reliability and Validity of the Adolescent Stress Questionnaire in a Sample of European Adolescents--the HELENA Study

BMC Public Health. 2011  |  Pubmed ID: 21943341

Since stress is hypothesized to play a role in the etiology of obesity during adolescence, research on associations between adolescent stress and obesity-related parameters and behaviours is essential. Due to lack of a well-established recent stress checklist for use in European adolescents, the study investigated the reliability and validity of the Adolescent Stress Questionnaire (ASQ) for assessing perceived stress in European adolescents.

Bone Related Health Status in Adolescent Cyclists

PloS One. 2011  |  Pubmed ID: 21980360

To describe bone status and analyse bone mass in adolescent cyclists.

Physical Activity Among Spanish Adolescents: Relationship with Their Relatives' Physical Activity - the AVENA Study

Journal of Sports Sciences. Feb, 2011  |  Pubmed ID: 21184343

Identifying factors related to physical activity levels in young people is important for a more efficient health promotion. The aims of this study were to assess physical activity levels in a national sample of urban Spanish adolescents, and to examine the association between significant others' physical activity (father, mother, brother, sister, and close friends) and that of the adolescents. The present study comprised 2260 adolescents (1157 boys, 1103 girls) aged 13.0-18.5 years participating in the AVENA Study. Both the adolescents' physical activity and that of their relatives and close friends was assessed by questionnaire. The odds of being active were higher in boys than girls (odds ratio = 2.79, 95% confidence interval = 2.34-3.33) and tended to decrease across age groups in both boys and girls. Father's and older brother's physical activity was associated with boys' physical activity, while that of any significant other was associated with girls' physical activity. When both parents reported being active, boys had nearly two times higher odds of being active and girls had nearly three times higher odds of being active. The physical activity levels of Spanish adolescents are in line with those previously reported. Physical activity levels in girls are strongly related to the physical activity of any significant other, whereas physical activity levels in boys are only related to their male relatives' physical activity.

Excessive Sedentary Time and Low Cardiorespiratory Fitness in European Adolescents: the HELENA Study

Archives of Disease in Childhood. Mar, 2011  |  Pubmed ID: 21220264

The aims of this study were to examine what amount of sedentary time is associated with low cardiorespiratory fitness (CRF) in adolescents and whether this association is independent of physical activity.

Evaluation of Iron Status in European Adolescents Through Biochemical Iron Indicators: the HELENA Study

European Journal of Clinical Nutrition. Mar, 2011  |  Pubmed ID: 21245877

To assess the iron status among European adolescents through selected biochemical parameters in a cross-sectional study performed in 10 European cities.

Breastfeeding in Infancy is Not Associated with Inflammatory Status in Healthy Adolescents

The Journal of Nutrition. Mar, 2011  |  Pubmed ID: 21248197

It has been suggested that breast-feeding (BF) may be associated with a decreased risk of cardiovascular disease in adulthood. A low-grade inflammation is associated with an increased risk of cardiovascular disease, even in apparently healthy children. The objective of this study was to assess the potential modulating effect of BF on the inflammatory status of healthy adolescents. Information on BF (duration) was obtained from parental records in 484 of 1040 healthy European urban adolescents (56.4% females) that had a blood sample obtained as part of the Healthy Lifestyle in Europe by Nutrition and Adolescence study. Blood serum inflammatory markers were measured, including high sensitivity C-reactive protein, complement factors 3 and 4, ceruloplasmin, adhesion molecules (L-selectin and soluble endothelial selectin, soluble vascular cell adhesion molecule 1, and intercellular adhesion molecule 1), cytokines, TGFβ1, and white blood cells. After univariate analysis, a propensity score, including the potential confounding factors, was computed and used to assess the association between BF and selected inflammatory markers. BF was not significantly associated with any of the selected inflammatory markers after adjustment for gender and propensity score. In our study, BF was not associated with low-grade inflammatory status in healthy adolescents, suggesting that the potential cardiovascular benefits of BF are related to other mechanisms than modulation of inflammation or might become relevant at a later age. Groups at high risk for cardiovascular disease should be a target for further research concerning the effects of BF.

Pilot Evaluation of the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Food-O-Meter, a Computer-tailored Nutrition Advice for Adolescents: a Study in Six European Cities

Public Health Nutrition. Jan, 2011  |  Pubmed ID: 21281542

OBJECTIVE: To investigate the feasibility and impact of the Food-O-Meter, an Internet-based computer-tailored nutrition intervention in adolescents. DESIGN: Participants in the intervention condition received the computer-tailored advice at baseline and at 1 month, those in the control condition received standardised advice. Effects were evaluated at 1 month (n 621) and at 3 months (n 558) using multi-level modelling. SETTING: Secondary schools in six European cities. Adolescents accessed the intervention in the school computer room under the supervision of teachers. SUBJECTS: Classes with students aged 12-17 years in the schools participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) cross-sectional study were randomised into intervention and control schools. RESULTS: In most participating centres the intervention was feasible and generally well appreciated, especially by girls. Technical problems and lack of motivation of the teachers hindered implementation in some centres. Overweight adolescents had higher scores for reading and using the advice than normal weight adolescents. After 1 month adolescents receiving the standardised advice reported an increase in fat intake, while fat intake in the intervention condition was stable (F = 4·82, P < 0·05). After 3 months, there was a trend in the total group for an intervention effect of the tailored advice on fat intake (F = 2·80, P < 0·10). In the overweight group there was a clear positive effect (F = 5·76, P < 0·05). CONCLUSIONS: The Food-O-Meter should be developed further. The results were modest but clear for percentage energy from fat, specifically in the overweight group. Adaptations based on new research are needed to enhance the reliability and effectiveness of the intervention.

Relationship Between Self-reported Dietary Intake and Physical Activity Levels Among Adolescents: the HELENA Study

The International Journal of Behavioral Nutrition and Physical Activity. 2011  |  Pubmed ID: 21294914

Evidence suggests possible synergetic effects of multiple lifestyle behaviors on health risks like obesity and other health outcomes. Therefore it is important to investigate associations between dietary and physical activity behavior, the two most important lifestyle behaviors influencing our energy balance and body composition. The objective of the present study is to describe the relationship between energy, nutrient and food intake and the physical activity level among a large group of European adolescents.

Associations Between Common Genetic Polymorphisms in the Liver X Receptor Alpha and Its Target Genes with the Serum HDL-cholesterol Concentration in Adolescents of the HELENA Study

Atherosclerosis. May, 2011  |  Pubmed ID: 21316679

Genetic variability in the NR1H3 gene (encoding LXRα) and in several of its target genes is associated with serum HDL-cholesterol (HDL-C) concentrations. We sought to assess if these associations could be detected in adolescents.

Food and Drink Intake During Television Viewing in Adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study

Public Health Nutrition. Sep, 2011  |  Pubmed ID: 21338558

To compare food consumption during television (TV) viewing among adolescents who watched >2 h/d v. ≤2 h/d; and to examine the association between sociodemographic variables (age, gender and socio-economic status (SES)) and the consumption of energy-dense foods and drinks during TV viewing.

Breakfast Habits and Factors Influencing Food Choices at Breakfast in Relation to Socio-demographic and Family Factors Among European Adolescents. The HELENA Study

Appetite. Jun, 2011  |  Pubmed ID: 21376767

Breakfast consumption has been shown to be an important indicator of a healthy lifestyle. Little is known however about factors influencing breakfast consumption and food choices at breakfast in adolescents. The aim of the present study was therefore to describe breakfast habits, and factors influencing food choices at breakfast within the framework of the EU-funded HELENA Study, in 3528 adolescents from ten European cities. Additionally, socio-demographic differences in breakfast habits and in influencing factors were investigated. Half of the adolescents (and fewer girls than boys) indicated being regular breakfast consumers. Girls with mothers with a high level of education, boys from 'traditional' families and boys who perceived low family affluence were positively associated with breakfast consumption. Boys whose parents gave encouragement and girls whose peers ate healthily were more likely to be regular breakfast consumers. 'Hunger', 'taste', 'health concerns' and 'parents or guardian' were the most important influences on the adolescents' food choices at breakfast. Adolescents from southern Europe and girls reported to be more influenced by personal and socio-environmental factors. Socio-demographic differences, in particular regional and gender differences, need to be considered in discussions surrounding the development of nutritional intervention programs intended for adolescents.

Fat and Lean Masses in Youths with Down Syndrome: Gender Differences

Research in Developmental Disabilities. Sep-Oct, 2011  |  Pubmed ID: 21435834

The present study aimed at comparing fat and lean masses between children and adolescents with and without Down syndrome (DS) and evaluating the presence of sexual dimorphism. Total and regional fat and lean masses were assessed by dual energy X-ray absorptiometry (DXA) and the percentage of body fat (%BF) by air-displacement plethysmography (ADP) in 31 participants with DS and 32 controls. Waist circumference (WC) was also measured. Analysis of covariance and the Student's t-test were used to compare variables between groups and between sexes within the same group. There were no significant differences in %BF, WC or body mass index (BMI) between groups. Females with DS showed higher fat and lean masses in the trunk, and lower fat and lean masses in the lower limbs compared with females without DS (all p≤0.05). Males with DS showed higher fat masses in the whole body and upper limbs, and lower lean masses in the whole body and lower limbs compared with males without DS (all p≤0.05). Females in both groups showed higher levels of fat, and lower levels of lean than did their respective males (all p≤0.05). Youths with DS showed higher fat and lower lean than their non-DS peers. The increased truncal fat in females with DS might indicate a higher risk of metabolic syndrome in this group. Sexual dimorphism in youths with and without DS was very similar. BMI, WC and %BF were not effective indicators of increased risk in youths with DS.

The International Fitness Scale (IFIS): Usefulness of Self-reported Fitness in Youth

International Journal of Epidemiology. Jun, 2011  |  Pubmed ID: 21441238

We examined: (i) the usefulness of the International Fitness Scale (IFIS) to correctly rank adolescents into physical fitness levels; (ii) the capacity of the IFIS for predicting cardiovascular disease (CVD) risk; and (iii) the reliability of the IFIS in adolescents.

Comparison of the IPAQ-A and Actigraph in Relation to VO2max Among European Adolescents: the HELENA Study

Journal of Science and Medicine in Sport / Sports Medicine Australia. Jul, 2011  |  Pubmed ID: 21444243

The purpose was to compare data obtained from a modified, long, self-administered version of the International Physical Activity Questionnaire (IPAQ-A) with objective data obtained in parallel from Actigraph accelerometers, and VO(2)max in adolescents. The study comprised a total of 2018 adolescents (46% male) from ten European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. Physical activity was assessed over seven consecutive days by accelerometry and expressed as min/day of moderate, vigorous, and moderate to vigorous (MVPA) physical activity (PA). PA was also assessed with the IPAQ-A. VO(2)max was estimated from a 20-m shuttle run test. Poor to fair correlations between the two methodologies were found for the whole study sample and when stratified by age and gender (r(s) = 0.08-0.26, p < 0.01). On average, the self-reported time spent in moderate PA was higher compared to the time measured with the accelerometer, while the differences between both instruments were less clear for vigorous intensity. Adolescents reporting high levels of PA (3rd tertile IPAQ-A) also showed higher levels of PA (accelerometers) in all the study variables (moderate, vigorous and MVPA), compared to adolescents reporting low PA (1st tertile IPAQ-A) (all p < 0.001). Both methods were moderately correlated with estimated VO(2)max. Within the HELENA-study, the IPAQ-A showed the modest comparability with the accelerometer data for assessing PA in each intensity level and was the highest for vigorous intensity. Both instruments are able to detect the adolescents with the highest cardio respiratory fitness, which are the most active adolescents.

Objectively Measured Physical Activity and Sedentary Time in European Adolescents: the HELENA Study

American Journal of Epidemiology. Jul, 2011  |  Pubmed ID: 21467152

The authors' aim in this cross-sectional study was to characterize levels of objectively measured physical activity and sedentary time in adolescents from 9 European countries. The study comprised 2,200 European adolescents (1,184 girls) participating in the HELENA cross-sectional study (2006-2008). Physical activity was measured by accelerometry and was expressed as average intensity (counts/minute) and amount of time (minutes/day) spent engaging in moderate- to vigorous-intensity physical activity (MVPA). Time spent in sedentary behaviors was also objectively measured. Cardiorespiratory fitness was measured by means of the 20-m shuttle run test. Level of maternal education was reported by the adolescents. A higher proportion of boys (56.8% of boys vs. 27.5% of girls) met the physical activity recommendations of at least 60 minutes/day of MVPA. Adolescents spent most of the registered time in sedentary behaviors (9 hours/day, or 71% of the registered time). Both average intensity and MVPA were higher in adolescents with high cardiorespiratory fitness, and sedentary time was lower in the high-fitness group. There were no physical activity or sedentary time differences between maternal education categories. These data provide an objective measure of physical activity and amount of time spent in sedentary behaviors in a relatively large number of European adolescents.

Muscular and Cardiorespiratory Fitness Are Independently Associated with Metabolic Risk in Adolescents: the HELENA Study

Pediatric Diabetes. Dec, 2011  |  Pubmed ID: 21470352

To examine the independent associations of muscular and cardiorespiratory fitness with clustered metabolic risk in adolescents.

Reliability and Validity of a Screen Time-based Sedentary Behaviour Questionnaire for Adolescents: The HELENA Study

European Journal of Public Health. Apr, 2011  |  Pubmed ID: 21498560

BACKGROUND: Although there is a growing interest in the epidemiology of sedentary behaviours, it is unknown whether sedentary behaviour questionnaires are broad markers of sedentary time. The aims of this study were to determine the: (i) reliability of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) screen time-based sedentary behaviour questionnaire; and (ii) its validity, i.e. the ability of the questionnaire to correctly rank adolescents according to the objectively measured sedentary time. METHODS: A total of 183 adolescents (104 females aged 12.5-17.5 years) were involved in the reliability study. Participants completed the HELENA sedentary questionnaire twice (1 week apart). The validity study comprised 2048 (1212 females) adolescents (12.5-17.5 years of age) included in the HELENA cross-sectional study. Questions included television viewing, computer games, console games, Internet for study and non-study reasons and study during week and weekend days. We compared median values of sedentary time, using accelerometers, by tertiles of self-reported sedentary behaviours and their sum (composite sedentary score). RESULTS: Reliability study: κ-values showed a good agreement (>0.7), except for Internet for study reasons (0.46 weekdays, 0.33 weekend). The questionnaire correctly classified boys' sedentary time when analysed by specific behaviours and by a composite sedentary score. In girls, median values of objectively measured sedentary time were not different across tertiles of self-reported sedentary behaviours or the composite sedentary score. CONCLUSION: The HELENA sedentary questionnaire is reliable, yet only correctly classifies objectively measured sedentary time in boys.

Interrater Reliability and Time Measurement Validity of Speed-agility Field Tests in Adolescents

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jul, 2011  |  Pubmed ID: 21499136

The aim of this study was to examine the interrater reliability (trained vs. untrained raters) and criterion-related validity (manual vs. automatic timing) of the 4 × 10-m shuttle run and 30-m running speed tests (times measured). The study comprised 85 adolescents (38 girls) aged 13.0-16.9 years from the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The time required to complete the 4 × 10-m shuttle run and 30-m running tests was simultaneously measured (a) manually with a stopwatch by both trained and untrained raters (for interrater reliability analysis), and (b) by using photoelectric cells (for validity analysis). Systematic error, random error, and heteroscedasticity were studied with repeated-measured analysis of variance and Bland-Altman plots. The systematic error for untrained vs. trained raters and the untrained raters vs. photoelectric cells were in all cases ∼0.1 seconds (p < 0.01), that is, untrained raters recorded higher times. No systematic error was found between trained raters and photoelectric cells (p > 0.05). No heteroscedasticity was shown in any case (p > 0.05). The findings indicate that manual measurements by a trained rater, using a stopwatch, seem to be a valid method to assess speed and agility fitness testing in adolescents. Researchers must be trained to minimize the measurement error.

The Effect of Ponderal Index at Birth on the Relationships Between Common LEP and LEPR Polymorphisms and Adiposity in Adolescents

Obesity (Silver Spring, Md.). Oct, 2011  |  Pubmed ID: 21512510

This study examined the effect of ponderal index (PI) at birth on the relationships between eight common polymorphisms of the leptin (LEP) and leptin receptor (LEPR) genes and adiposity in adolescents. A total of 823 European adolescents (45.4% girls) aged 14.8 ± 1.4 years were genotyped for the LEP (rs2167270, rs12706832, rs10244329, rs2071045, and rs3828942) and LEPR (rs1137100, rs1137101, and rs8179183) polymorphisms. The PI was calculated from parental reports of birth weight and length. Fat mass index (FMI) was calculated. Analyses were adjusted for relevant confounders. An "adiposity-risk-allele score" based on genotypes at the three single-nucleotide polymorphisms (SNPs) associated with adolescents' FMI in adolescents within the lower tertile of PI was calculated. The LEP rs10244329 and rs3828942 polymorphisms were associated with higher FMI only in adolescents within the lower PI tertile (+0.55 kg/m(2) per minor T allele, P = 0.040, and +0.58 kg/m(2) per major G allele, P = 0.028, respectively). The LEPR rs8179183 polymorphism was significantly associated with higher FMI in adolescents within the lower PI tertile (+0.87 kg/m(2) per minor C allele, P = 0.006). After correction for multiple comparisons, only the association between the LEPR rs8179183 and FMI persisted. However, each additional risk allele conferred 0.53 kg/m(2) greater FMI in adolescents within the lower tertile of PI (P = 0.008). In conclusion, our results suggest that those adolescents born with lower PI could be more vulnerable to the influence of the LEP rs10244329 and rs3828942 polymorphisms and LEPR rs8179183 polymorphism on total adiposity content. Due to the relatively small sample size, these findings should be replicated in further larger population samples.

Factors That Influence Weekday Sleep Duration in European Children

Sleep. May, 2011  |  Pubmed ID: 21532957

To compare nocturnal sleep duration in children from 8 European countries and identify its determinants.

Associations of Birth Weight with Serum Long Chain Polyunsaturated Fatty Acids in Adolescents; the HELENA Study

Atherosclerosis. Jul, 2011  |  Pubmed ID: 21550607

Nutritional factors in early life may have long-term physiologic effects in humans. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) play important roles in protecting against cardiovascular disease (CVD) risk. Our aim was to examine the association of birth weight (BW) with serum long chain polyunsaturated fatty acids (LCPUFA) profile in adolescents.

Levels of Physical Activity That Predict Optimal Bone Mass in Adolescents: the HELENA Study

American Journal of Preventive Medicine. Jun, 2011  |  Pubmed ID: 21565650

Physical activity is necessary for bone mass development in adolescence. There are few studies quantifying the associations between physical activity and bone mass in adolescents.

Combined Influence of Lifestyle Risk Factors on Body Fat in Spanish Adolescents--the Avena Study

Obesity Facts. 2011  |  Pubmed ID: 21577017

To examine the combined influence of four lifestyle risk factors related to physical activity, television viewing, sleep duration, and meal frequency on body fat (BF) in adolescents.

Clustering Patterns of Physical Activity, Sedentary and Dietary Behavior Among European Adolescents: The HELENA Study

BMC Public Health. 2011  |  Pubmed ID: 21586158

Evidence suggests possible synergetic effects of multiple lifestyle behaviors on health risks like obesity and other health outcomes. A better insight in the clustering of those behaviors, could help to identify groups who are at risk in developing chronic diseases. This study examines the prevalence and clustering of physical activity, sedentary and dietary patterns among European adolescents and investigates if the identified clusters could be characterized by socio-demographic factors.

FADS1 Genetic Variability Interacts with Dietary α-linolenic Acid Intake to Affect Serum Non-HDL-cholesterol Concentrations in European Adolescents

The Journal of Nutrition. Jul, 2011  |  Pubmed ID: 21593353

Two rate-limiting enzymes in PUFA biosynthesis, Δ5- and Δ6-desaturases, are encoded by the FADS1 and FADS2 genes, respectively. Genetic variants in the FADS1-FADS2 gene cluster are associated with changes in plasma concentrations of PUFA, HDL- and LDL-cholesterol, and TG. However, little is known about whether dietary PUFA intake modulates these associations, especially in adolescents. We assessed whether dietary linoleic acid (LA) or α-linolenic acid (ALA) modulate the association between the FADS1 rs174546 polymorphism and concentrations of PUFA, other lipids, and lipoproteins in adolescents. Dietary intakes of LA and ALA, FADS1 rs174546 genotypes, PUFA levels in serum phospholipids, and serum concentrations of TG, cholesterol, and lipoproteins were determined in 573 European adolescents from the HELENA study. The sample was stratified according to the median dietary LA (≤9.4 and >9.4 g/d) and ALA (≤1.4 and >1.4 g/d) intakes. The associations between FADS1 rs174546 and concentrations of PUFA, TG, cholesterol, and lipoproteins were not affected by dietary LA intake (all P-interaction > 0.05). Similarly, the association between the FADS1 rs174546 polymorphism and serum phospholipid concentrations of ALA or EPA was not modified by dietary ALA intake (all P-interaction > 0.05). In contrast, the rs174546 minor allele was associated with lower total cholesterol concentrations (P = 0.01 under the dominant model) and non-HDL-cholesterol concentrations (P = 0.02 under the dominant model) in the high-ALA-intake group but not in the low-ALA-intake group (P-interaction = 0.01). These results suggest that dietary ALA intake modulates the association between FADS1 rs174546 and serum total and non-HDL-cholesterol concentrations at a young age.

Role of Dietary Factors and Food Habits in the Development of Childhood Obesity: a Commentary by the ESPGHAN Committee on Nutrition

Journal of Pediatric Gastroenterology and Nutrition. Jun, 2011  |  Pubmed ID: 21593641

This Comment by the Committee on Nutrition of the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition aims to provide a summary of the role of nutrition-related factors on obesity prevention in children ages 2 to 18 years. This Comment emphasizes that dietary interventions should be incorporated into a multidisciplinary strategy for obesity prevention. No single nutrient has been unequivocally associated with the development of obesity. Methodological limitations in study design and the complex nature of obesity must be taken into account when interpreting the association with reported dietary factors. Energy intake should be individually determined, taking into account energy expenditure and growth. Preferential intake of slowly absorbed carbohydrates and limiting the ingestion of rapidly absorbed carbohydrates and simple sugars should be promoted. No specific recommendations for macronutrient intakes to prevent obesity can be made. Plant foods can be used as the main food contributors to a well-balanced diet with adequate monitoring of nutrient intake. Plain water should be promoted as the main source of fluids for children instead of sugar-sweetened beverages. Children should eat at least 4 meals, including breakfast, every day. Regular family meals should be encouraged. Regular consumption of fast food with large portion sizes and high energy density should be avoided. Healthy food options should be promoted for snacking. Food portion sizes should be appropriate for age and body size. Nutrition and lifestyle education aimed at the prevention of obesity should be included in the routine care of children by health care professionals.

Changes in Cardiometabolic Risk Factors, Appetite-controlling Hormones and Cytokines After a Treatment Program in Overweight Adolescents: Preliminary Findings from the EVASYON Study

Pediatric Diabetes. Jun, 2011  |  Pubmed ID: 21615652

We investigated the effects of the EVASYON program on body fatness, cardiometabolic risk factors, gut appetite-controlling hormones and serum levels of cytokines in adolescents with overweight or obesity (OW/OB).

Fitness and Fatness Are Independently Associated with Markers of Insulin Resistance in European Adolescents; the HELENA Study

International Journal of Pediatric Obesity : IJPO : an Official Journal of the International Association for the Study of Obesity. Aug, 2011  |  Pubmed ID: 21623681

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.

Active Commuting and Physical Activity in Adolescents from Europe: Results from the HELENA Study

Pediatric Exercise Science. May, 2011  |  Pubmed ID: 21633133

We assessed commuting patterns in adolescents from 10 European cities and examined associations with physical activity (PA). A total of 3112 adolescents were included. PA was objectively measured with accelerometry. Commuting patterns and overall PA were self-reported using questions from the International Physical Activity Questionnaire modified for adolescents (IPAQ-A). Adolescents reported to spend 30 min (15,60) [expressed as median (25th, 75th percentiles)] walking. In boys, associations between active commuting (walking and biking) and PA levels were observed for moderate, moderate-to-vigorous and overall PA. In girls, these associations were observed for moderate and moderate-to-vigorous PA (walking). Similar results were found with the IPAQ-A. We observed positive associations between overall commuting and PA levels in European adolescents, yet due to the cross-sectional study design we cannot state the direction of these. Future studies should address the causation between active commuting and PA levels.

Supplementation of N-3 LCPUFA to the Diet of Children Older Than 2 Years: a Commentary by the ESPGHAN Committee on Nutrition

Journal of Pediatric Gastroenterology and Nutrition. Jul, 2011  |  Pubmed ID: 21694531

The aim of this commentary is to review data on the effect of supplementation of paediatric patients ages 2 years or older with n-3 long-chain polyunsaturated fatty acids (LCPUFA). Some evidence for a positive effect on functional outcome in children with attention-deficit/hyperactivity disorder (ADHD) was found; however, benefit was seen in only about half of the randomised controlled trials (RCT), and studies varied widely not only in dose and form of supplementation but also in the functional outcome parameter tested. The committee concludes that there are insufficient data to recommend n-3 LCPUFA supplementation in the treatment of children with ADHD, but further research on n-3 LCPUFA supplementation in ADHD may be worthwhile. The committee was unable to find evidence of a favourable effect of n-3 LCPUFA supplementation on cognitive function in children. Although no benefit of n-3 LCPUFA supplementation was seen for major clinical outcome parameters in children with cystic fibrosis, a potentially beneficial shift towards less-inflammatory eicosanoid profiles seen in 2 studies provides grounds for further investigation; it is possible that earlier and longer supplementation periods may be needed to demonstrate clinical effect. For children with phenylketonuria, the limited data available suggest that supplementation of n-3 LCPUFA to the diet is both feasible and safe, but offers only transient benefit in visual function. For children with bronchial asthma there are insufficient data to suggest that LCPUFA supplementation has a beneficial effect. The committee advises paediatricians that most health claims about supplementation of n-3 LCPUFA in various diseases in children and adolescents are not supported by convincing scientific data.

Sexual Dimorphism in the Early Life Programming of Serum Leptin Levels in European Adolescents: the HELENA Study

The Journal of Clinical Endocrinology and Metabolism. Aug, 2011  |  Pubmed ID: 21697251

The aim of this study was to test the hypothesis that a lower birth weight, as an indicator of adverse intrauterine environment, is associated with higher serum leptin levels in European adolescents. We also examined the possible sexual dimorphism in this relationship.

Sleep Duration and Overweight in European Children: is the Association Modified by Geographic Region?

Sleep. Jul, 2011  |  Pubmed ID: 21731138

To investigate differences and a possible effect modification by geographical region in the association between sleep duration and overweight.

Physical Activity Attenuates the Effect of Low Birth Weight on Insulin Resistance in Adolescents: Findings from Two Observational Studies

Diabetes. Sep, 2011  |  Pubmed ID: 21752955

To examine whether physical activity influences the association between birth weight and insulin resistance in adolescents.

Associations Between Parental Educational/occupational Levels and Cognitive Performance in Spanish Adolescents: the AVENA Study

Psicothema. Aug, 2011  |  Pubmed ID: 21774884

We examined the associations between parental educational/occupational levels and cognitive performance in Spanish adolescents. Cognitive performance was measured by a validated Scholar Aptitudes test in 2,162 participants. Parental educational and occupational levels were positively associated with all specific cognitive abilities and the overall score (p<001 to .04). The odds ratios of having a high cognitive performance (top quartile) in adolescents with high parental educational level were 1.6 to 1.7 times higher than for those with a low parental educational level. Similarly, the odds ratios were 1.9 to 2.4 times higher for adolescents with high parental occupational level. These findings suggest an association between parental educational/occupational levels and cognitive performance in Spanish adolescents and support the parents' role in the creation of a stimulating intellectual environment.

Using the Intervention Mapping Protocol to Develop a Community-based Intervention for the Prevention of Childhood Obesity in a Multi-centre European Project: the IDEFICS Intervention

The International Journal of Behavioral Nutrition and Physical Activity. 2011  |  Pubmed ID: 21806806

The prevalence of childhood obesity has increased during the past decades and is now considered an urgent public health problem. Although stabilizing trends in obesity prevalence have been identified in parts of Europe, preventive efforts in children are still needed. Using the socio-ecological approach as the underlying theoretical perspective, the IDEFICS project aimed to develop, implement and evaluate a community-based intervention for the prevention of childhood obesity in eight European countries. The aim of the present manuscript was to describe the content and developmental process of the IDEFICS intervention.

Nutritional Knowledge in European Adolescents: Results from the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Public Health Nutrition. Aug, 2011  |  Pubmed ID: 21810282

OBJECTIVE: To build up sufficient knowledge of a 'healthy diet'. Here, we report on the assessment of nutritional knowledge using a uniform method in a large sample of adolescents across Europe. DESIGN: A cross-sectional study. SETTING: The European multicentre HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study conducted in 2006-2007 in ten cities in Austria, Belgium, France, Germany, Greece (one inland and one island city), Hungary, Italy, Spain and Sweden. SUBJECTS: A total of 3546 adolescents (aged 12·5-17·5 years) completed a validated nutritional knowledge test (NKT). Socio-economic variables and anthropometric data were considered as potential confounders. RESULTS: NKT scores increased with age and girls had higher scores compared with boys (62 % v. 59 %; P < 0·0001). Scores were approximately 10 % lower in 'immigrant' adolescents or in adolescents with 'immigrant' mothers. Misconceptions with respect to the sugar content in food or in beverages were found. Overall, there was no correlation between BMI values and NKT scores. After categorization according to BMI, scores increased significantly with BMI group only in boys. These differences disappeared after controlling for socio-economic status (SES). Smoking status and educational level of the mother influenced the NKT scores significantly in boys, as well as the educational levels of both parents in girls. CONCLUSIONS: Nutritional knowledge was modest in our sample. Interventions should be focused on the lower SES segments of the population. They should be initiated at a younger age and should be combined with environmental prevention (e.g. healthy meals in school canteens).

A Combined Training Intervention Programme Increases Lean Mass in Youths with Down Syndrome

Research in Developmental Disabilities. Nov, 2011  |  Pubmed ID: 21820861

The present study aimed to determine whether youths with Down syndrome (DS) are able to increase lean mass and decrease fat mass, after 21 weeks of conditioning combined with a plyometric jumps training program.

Vitamin D Status Among Adolescents in Europe: the Healthy Lifestyle in Europe by Nutrition in Adolescence Study

The British Journal of Nutrition. Mar, 2012  |  Pubmed ID: 21846429

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.

Reliability and Intermethod Agreement for Body Fat Assessment Among Two Field and Two Laboratory Methods in Adolescents

Obesity (Silver Spring, Md.). Jan, 2012  |  Pubmed ID: 21869760

To increase knowledge about reliability and intermethods agreement for body fat (BF) is of interest for assessment, interpretation, and comparison purposes. It was aimed to examine intra- and inter-rater reliability, interday variability, and degree of agreement for BF using air-displacement plethysmography (Bod-Pod), dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), and skinfold measurements in European adolescents. Fifty-four adolescents (25 females) from Zaragoza and 30 (14 females) from Stockholm, aged 13-17 years participated in this study. Two trained raters in each center assessed BF with Bod-Pod, DXA, BIA, and anthropometry (DXA only in Zaragoza). Intermethod agreement and reliability were studied using a 4-way ANOVA for the same rater on the first day and two additional measurements on a second day, one each rater. Technical error of measurement (TEM) and percentage coefficient of reliability (%R) were also reported. No significant intrarater, inter-rater, or interday effect was observed for %BF for any method in either of the cities. In Zaragoza, %BF was significantly different when measured by Bod-Pod and BIA in comparison with anthropometry and DXA (all P < 0.001). The same result was observed in Stockholm (P < 0.001), except that DXA was not measured. Bod-Pod, DXA, BIA, and anthropometry are reliable for %BF repeated assessment within the same day by the same or different raters or in consecutive days by the same rater. Bod-Pod showed close agreement with BIA as did DXA with anthropometry; however, Bod-Pod and BIA presented higher values of %BF than anthropometry and DXA.

Critical Systematic Review of the Level of Evidence for Routine Use of Probiotics for Reduction of Mortality and Prevention of Necrotizing Enterocolitis and Sepsis in Preterm Infants

Clinical Nutrition (Edinburgh, Scotland). Feb, 2012  |  Pubmed ID: 21996513

Probiotics have been suggested to prevent severe necrotizing enterocolitis (NEC) and decrease mortality in preterm infants. The aim of this paper was to systematically analyze the level of evidence (LoE) of published controlled randomized trials (RCTs) on probiotics in preterm infants.

Blood Cells As a Source of Transcriptional Biomarkers of Childhood Obesity and Its Related Metabolic Alterations: Results of the IDEFICS Study

The Journal of Clinical Endocrinology and Metabolism. Jan, 2012  |  Pubmed ID: 22278432

Background:IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants Project) is a European multicenter study on childhood obesity. One of its goals is to define early biomarkers of risk associated with obesity and its comorbid conditions.Objective:We considered blood cells as a new potential source of transcriptional biomarkers for these metabolic disorders and examined whether blood cell mRNA levels of some selected genes (LEPR, INSR, CPT1A, SLC27A2, UCP2, FASN, and PPARα) were altered in overweight children and whether their expression levels could be defined as markers of the insulin-resistant or dyslipidemic state associated with overweight.Design:Blood samples were obtained from 306 normal-weight and overweight children, aged 2-9 yr, from eight different European countries. Whole-blood mRNA levels were assessed by quantitative RT-PCR.Results:LEPR, INSR, and CPT1A mRNA levels were higher in overweight compared with normal-weight children (the two latter only in males), whereas SLC27A2 mRNA levels were lower in overweight children. Significant associations were also found between expression levels of LEPR, INSR, CPT1A, SLC27A2, FASN, PPARα, and different parameters, including body mass index, homeostasis model assessment index, and plasma triglycerides and cholesterol levels. These associations showed that high expression levels of CPT1A, SLC27A2, INSR, FASN, or PPARα may be indicative of a lower risk for the insulin-resistant or dyslipidemic state associated with obesity, whereas low LEPR mRNA levels appear as a marker of high low-density lipoprotein cholesterol, independently of body mass index.Conclusions:These findings point toward the possibility of using the expression levels of these genes in blood cells as markers of metabolic status and can potentially provide an early warning of a future disorder.

Food Intake of European Adolescents in the Light of Different Food-based Dietary Guidelines: Results of the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Public Health Nutrition. Mar, 2012  |  Pubmed ID: 21936969

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.

A Genome-wide Association Meta-analysis Identifies New Childhood Obesity Loci

Nature Genetics. Apr, 2012  |  Pubmed ID: 22484627

Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made in establishing genetic influences on common early-onset obesity. We performed a North American, Australian and European collaborative meta-analysis of 14 studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight newly discovered signals yielding association with P < 5 × 10(-6) in nine independent data sets (2,818 cases and 4,083 controls), we observed two loci that yielded genome-wide significant combined P values near OLFM4 at 13q14 (rs9568856; P = 1.82 × 10(-9); odds ratio (OR) = 1.22) and within HOXB5 at 17q21 (rs9299; P = 3.54 × 10(-9); OR = 1.14). Both loci continued to show association when two extreme childhood obesity cohorts were included (2,214 cases and 2,674 controls). These two loci also yielded directionally consistent associations in a previous meta-analysis of adult BMI(1).