Risk factors for overweight and obesity in Swiss primary school children: results from a representative national survey.

PURPOSE: Obesity is a global epidemic affecting around 10 % of 5- to 17-year olds. With the causes for obesity being multifactorial, a better understanding of the influencing factors is essential for effective treatment and prevention programs. The aim of this study was therefore to identify specific risk factors for overweight and obesity in children in Switzerland. METHODS: A nationally representative sample of children aged 6-12 years was recruited (n = 2724). Height and weight were measured to calculate BMI (kg/m(2)). In addition, a questionnaire was distributed to all children asking about their physical activity, media consumption, and dietary habits as well as some parental factors. RESULTS: The prevalence of overweight and obesity in boys was 11.8 and 7.5 %, respectively, and in girls, it was 11.9 and 5.7 %. In univariate analyses, a number of parental, dietary, and activity factors were shown to be associated with BMI category. Based on a multinomial logistic regression, parent nationality and media consumption were the most important factors predicting obesity in boys, while in girls it was parental education, nationality, and physical activity. CONCLUSION: We have demonstrated that parental nationality and education play an important role in the development of childhood obesity, together with media consumption and physical activity. However, risk factors are also different according to child gender. Thus, an important target group for the treatment and prevention of childhood obesity in Switzerland are immigrant families, and the problem needs to be tackled differently in boys and girls as their risk factors are not the same.

Antioxidant supplements reduced oxidative stress and stabilized liver function tests but did not reduce inflammation in a randomized controlled trial in obese children and adolescents.

Oxidative stress and low-grade systemic inflammation may contribute to the pathogenesis of obesity-induced comorbidities, including nonalcoholic fatty liver disease. Increasing intake of dietary antioxidants might be beneficial, but there are few data in obese children. To examine the effect of antioxidant supplementation on biomarkers of oxidative stress, inflammation, and liver function, we randomly assigned overweight or obese children and adolescents (n = 44; mean ± SD age: 12.7 ± 1.5 y) participating in a lifestyle modification program to a 4-mo intervention with daily antioxidants (vitamin E, 400 IU; vitamin C, 500 mg; selenium, 50 µg) or placebo. We measured anthropometrics, antioxidant status, oxidative stress (F(2)-isoprostanes, F(2)-isoprostane metabolites), inflammation, liver enzymes, fasting insulin and glucose, and lipid profile at baseline and endpoint. There was a significant treatment effect of antioxidant supplementation on antioxidant status [α-tocopherol, ß = 23.2 (95% CI: 18.0, 28.4); ascorbic acid, ß = 70.6 (95% CI: 51.7, 89.4); selenium, ß = 0.07 (95% CI: 0.01, 0.12)] and oxidative stress [8-iso-prostaglandin F2α, ß = -0.11 (95% CI: -0.19, -0.02)] but not on any of the inflammatory markers measured. There was a significant treatment effect on alanine aminotransferase [ß = -0.13 (95% CI: -0.23, -0.03)], a trend toward a significant effect on aspartate aminotransferase [ß = -0.04 (95% CI: -0.09, 0.01)], and no significant effect on γ-glutamyltransferase [ß = -0.03 (95% CI: -0.11, 0.06)]. In summary, antioxidant supplementation for 4 mo improved antioxidant-oxidant balance and modestly improved liver function tests; however, it did not reduce markers of systemic inflammation despite significant baseline correlations between oxidative stress and inflammation. The study was registered at clinicaltrials.gov as NCT01316081.

Pediatric adiposity stabilized in Switzerland between 1999 and 2012.

PURPOSE: Several countries have recently reported stabilization and/or a decrease in the prevalence of pediatric obesity. However, systematic, repeated national monitoring studies are scarce, and it is unclear whether this trend would be sustained. The objective was to present the latest overweight and obesity prevalence in Swiss children and to investigate trends in prevalence from 1999 to 2012. METHODS: Using probability-proportionate-to-size cluster sampling, nationally representative samples of children aged 6-12 years were recruited in 1999 (n = 594), 2002 (n = 2,493), 2004 (n = 328), 2007 (n = 2,218), 2009 (n = 907), and 2012 (n = 2,963). Height and weight were measured to calculate BMI (kg/m²). BMI cutoffs proposed by the Centers for Disease Control and Prevention (CDC) and by the International Obesity Task Force were used to determine the prevalence of overweight (excluding obesity) and obesity. Waist circumference was measured in 2007 and 2012, and multiple skinfold thicknesses assessed in 2002 and 2012. RESULTS: Using the CDC criteria, prevalences of overweight and obesity in 2012 were 11.9 % (95 % CI 10.7-13.1) and 7.1 % (95 % CI 6.2-8.0), respectively, and did not change between 1999 and 2012 (ß = -0.144, p = 0.293 and ß = -0.063, p = 0.552, respectively). Boys had significantly higher obesity prevalence than girls in 2007 (5.6 vs. 3.4 %) and 2012 (8.1 vs. 5.9 %). Percentage of children with excess waist circumference and body fat percentage did not differ between 2007 and 2012, and 2002 and 2012, respectively. CONCLUSION: Our data indicate the prevalence of childhood adiposity in Switzerland stabilized between 1999 and 2012, but ≈1 in 5 children remain overweight or obese and further efforts are needed to control the epidemic.

Moderate amounts of fructose consumption impair insulin sensitivity in healthy young men: a randomized controlled trial.

OBJECTIVE: Adverse effects of hypercaloric, high-fructose diets on insulin sensitivity and lipids in human subjects have been shown repeatedly. The implications of fructose in amounts close to usual daily consumption, however, have not been well studied. This study assessed the effect of moderate amounts of fructose and sucrose compared with glucose on glucose and lipid metabolism. RESEARCH DESIGN AND METHODS: Nine healthy, normal-weight male volunteers (aged 21-25 years) were studied in this double-blind, randomized, cross-over trial. All subjects consumed four different sweetened beverages (600 mL/day) for 3 weeks each: medium fructose (MF) at 40 g/day, and high fructose (HF), high glucose (HG), and high sucrose (HS) each at 80 g/day. Euglycemic-hyperinsulinemic clamps with [6,6]-(2)H(2) glucose labeling were used to measure endogenous glucose production. Lipid profile, glucose, and insulin were measured in fasting samples. RESULTS: Hepatic suppression of glucose production during the clamp was significantly lower after HF (59.4 ± 11.0%) than HG (70.3 ± 10.5%, P < 0.05), whereas fasting glucose, insulin, and C-peptide did not differ between the interventions. Compared with HG, LDL cholesterol and total cholesterol were significantly higher after MF, HF, and HS, and free fatty acids were significantly increased after MF, but not after the two other interventions (P < 0.05). Subjects' energy intake during the interventions did not differ significantly from baseline intake. CONCLUSIONS: This study clearly shows that moderate amounts of fructose and sucrose significantly alter hepatic insulin sensitivity and lipid metabolism compared with similar amounts of glucose.

Baseline leptin and leptin reduction predict improvements in metabolic variables and long-term fat loss in obese children and adolescents: a prospective study of an inpatient weight-loss program.

BACKGROUND: It is unclear whether high plasma leptin in obese individuals represents leptin resistance or whether individuals with marked reductions in leptin concentrations in response to weight loss may be at greater risk of regaining weight. Moreover, whether changes in leptin predict metabolic improvements during weight loss is uncertain. OBJECTIVE: The objective was to prospectively examine associations between plasma leptin, body fat, and weight and metabolic risk factors in obese children during weight loss. DESIGN: In obese children and adolescents [n = 203; mean age: 14.1 y, >98th body mass index (BMI) percentile for age and sex] participating in a 2-mo inpatient weight-loss program, we measured changes in body composition (by dual-energy X-ray absorptiometry), plasma leptin, insulin, and lipids. After discharge, anthropometric measures and plasma leptin were remeasured at 6 (n = 139) and 12 (n = 100) mo. RESULTS: During the 2-mo program, mean (±SD) weight and fat loss were 13.9 ± 4.0 kg and 9.2 ± 2.5 kg, respectively; and mean plasma leptin decreased by 76%. Weight and fat loss were sustained, and no significant differences in BMI-SD score (SDS) or body composition were found between 12 and 2 mo. Baseline leptin was a negative predictor for percentage fat loss at 2, 6, and 12 mo (P < 0.05). The percentage change in leptin during the 2-mo intervention positively correlated with the relative change in fasting insulin, the relative change in LDL cholesterol at 2 mo, percentage fat loss, and change in BMI-SDS at 2 and 6 mo (P < 0.02). CONCLUSIONS: Even in obese children with strongly elevated baseline leptin, large leptin reductions that predict short- and long-term loss of body fat and improvements in lipids and insulin sensitivity can be achieved. Thus, increased plasma leptin in obese children may not necessarily reflect leptin resistance; many children appear to remain leptin sensitive at this age.

During rapid weight loss in obese children, reductions in TSH predict improvements in insulin sensitivity independent of changes in body weight or fat.

BACKGROUND: Although serum TSH is often elevated in obesity and may be linked to disorders of lipid and glucose metabolism, the clinical relevance of these relationships remains unclear. SUBJECTS: Subjects were obese children and adolescents (n=206; mean age 14 yr) undergoing rapid weight and fat loss in a standardized, multidisciplinary, 2-month, in-patient weight loss program. DESIGN: This was a prospective study that determined thyroid function, glucose and lipid parameters, leptin, anthropometric measures, and body composition measured by dual-energy x-ray absorption at baseline and at the end of the intervention. RESULTS: At baseline, 52% of children had TSH concentrations in the high normal range (>2.5 mU/liter), but TSH was not correlated with body weight, body mass index sd scores, lean body mass, or body fat percentage. At baseline, independent of adiposity, TSH significantly correlated with total cholesterol (P=0.008), low-density lipoprotein cholesterol (P=0.013), fasting insulin (P=0.010), homeostatic model assessment (HOMA) (P=0.004), and leptin (P=0.006). During the intervention, mean body fat, TSH, HOMA, and fasting insulin decreased by 21, 11, 53, and 54%, respectively. Change (Δ) in TSH did not correlate with Δbody weight or Δbody composition, but ΔTSH significantly correlated with, Δfasting insulin and ΔHOMA, independent of Δbody weight or Δbody composition (P<0.05). CONCLUSION: TSH concentrations are elevated in obese children but are not correlated with the amount of excess body weight or fat. During weight loss, independent of changes in body weight or composition, decreases in elevated serum TSH predict decreases in fasting insulin and HOMA. These findings suggest interventions that target high TSH concentrations during weight loss in obese subjects may improve insulin sensitivity.