Dietary and physical activity patterns in French children are related to overweight and socioeconomic status

Clustering of dietary intake and sedentary behavior in 2-year-old children

OBJECTIVE

To examine clustering of energy balance-related behaviors (EBRBs) in young children. This is crucial because lifestyle habits are formed at an early age and track in later life. This study is the first to examine EBRB clustering in children as young as 2 years.

STUDY DESIGN

Cross-sectional data originated from the Child, Parent and Health: Lifestyle and Genetic Constitution (KOALA) Birth Cohort Study. Parents of 2578 2-year-old children completed a questionnaire. Correlation analyses, principal component analyses, and linear regression analyses were performed to examine clustering of EBRBs.

RESULTS

We found modest but consistent correlations in EBRBs. Two clusters emerged: a "sedentary-snacking cluster" and a "fiber cluster." Television viewing clustered with computer use and unhealthy dietary behaviors. Children who frequently consumed vegetables also consumed fruit and brown bread more often and white bread less often. Lower maternal education and maternal obesity were associated with high scores on the sedentary-snacking cluster, whereas higher educational level was associated with high fiber cluster scores.

CONCLUSIONS

Obesity-prone behavioral clusters are already visible in 2-year-old children and are related to maternal characteristics. The findings suggest that obesity prevention should apply an integrated approach to physical activity and dietary intake in early childhood.

Relation between socioeconomic status and body mass index: evidence of an indirect path via television use

OBJECTIVE

To test the hypothesis that media use mediates the relation between socioeconomic status (SES) and body mass index (BMI).

DESIGN

Analysis of 2 large cross-sectional surveys, 1 from Germany and 1 from the United States.

SETTING

Twenty-seven public schools in northern Germany; telephone interviews in the United States.

PARTICIPANTS

A total of 4810 German children and adolescents aged 10 to 17 years (mean age, 12.8 years); 4473 US children and adolescents aged 12 to 16 years (mean age, 14.0 years) recruited using random-digit-dial methods. Main Exposures Media exposure was assessed via survey questions about the presence of a television in the bedroom, television screen time, computer and video game screen time, and movie viewing. The SES was derived from type of school (German sample) or parental reports of their own education and family income (US sample).

MAIN OUTCOME MEASURES

The BMI was assessed by the use of self-reports in both samples, supplemented by parental reports (US sample) for height and weight.

RESULTS

In both samples, SES was inversely associated with BMI, and media use was directly associated with BMI. The effect of SES on overweight was partially mediated by media exposure, which explained 35% of the SES-BMI association in the German sample and 16% in the US sample. In both groups, television in the bedroom and television screen time had statistically significant indirect paths, whereas video game use and movie viewing did not.

CONCLUSIONS

Students from low-SES backgrounds are at higher risk for overweight in part because of higher levels of television viewing. The change of media use habits could modify this health disparity.

School meals in French secondary state schools with regard to the national recommendations

In 2001, a circular addressing both the composition of school meals and food safety issues was introduced in France to improve the nutrient composition of school meals and provided food-frequency guidelines to guarantee dietary balanced meals. The present study assesses the extent to which secondary state schools are familiar with and implement this circular. In 2005, a nationally representative sample of 1440 secondary state schools received a questionnaire on their catering service and the implementation of the circular's recommendations, and were requested to enclose all menus (lunches and dinners) served over 1 month. Menu analysis shows that progress is still required to achieve a meal composition in accordance with the food-group frequency guidelines appended to the circular. Some recommendations are followed by most of the schools, such as limiting high-fat products and providing plenty of raw fruits and vegetables, cooked vegetables and starchy foods. Other guidelines should be implemented further, especially with regard to the nutritional quality of main courses and dairy products, which are met by less than a third and a half of schools, respectively. Specific efforts are necessary for evening meals to ensure that the nutritional requirements of boarders are covered. Some recommendations, such as the food purchasing manager being trained in nutrition (38 % of schools) and the involvement of dietetic expertise when designing meals (6 %), seem to be linked to better dietary balance of meals. Implementation of the circular must therefore be promoted in schools and may require stronger regulatory nutrition standards and better cooperation between schools.

Are eating occasions and their energy content related to child overweight and socioeconomic status?

The objectives of this study were: (i) to assess the relationships between childhood overweight (OW) and four eating behaviors: daily eating frequency, and the relative contribution of breakfast, main meals (lunch and dinner), and snacks to total daily energy intake (EI); (ii) to explore whether these eating behaviors are involved in the negative association between socioeconomic status (SES) and OW. A representative sample of French children aged 3-11 years (n = 748) was taken from the 1998-1999 cross-sectional French INCA1 (Enquête Individuelle et Nationale sur les Consommations Alimentaires) food consumption survey. Food intake was reported in a 7-day food record, and SES, physical activity, sedentary behavior (SED), weight, and height were reported by answering face-to-face questionnaires. After adjusting for EI, physical activity, and SED, OW was positively associated with the contribution of the main meals to EI (P = 0.03), not significantly associated with the contribution of breakfast to EI, and inversely correlated to the number of eating episodes (P = 0.009) and to the contribution of snacking episodes to EI (P = 0.007). Our data suggest that a combination of more frequent intake occasions and lower contribution of the main meals to total daily EI is associated with a smaller risk of OW in children. However, eating frequency was the only eating behavior that played a slight mediation role (contributing approximately 8%) in the inverse relationship between SES and OW.

Physical activity, sedentary behaviour and energy balance in the preschool child: opportunities for early obesity prevention

Prevalence of obesity in preschool children has increased dramatically in recent years. The preschool years (age 3–6 years) have been regarded as critical for the programming of energy balance, via the concept of early ‘adiposity rebound’. Children who undergo early adiposity rebound are at increased risk of later obesity. Recent evidence suggests that associations between timing of adiposity rebound and later obesity may not reflect programming, but might denote that ‘obesogenic’ growth trajectories are often established by the preschool period. Studies of objectively-measured physical activity and sedentary behaviour in preschool children show that levels of physical activity are typically low and sedentary behaviour high. The review of evidence presented here is supportive of the hypothesis that physical activity is protective against obesity in the preschool period, and that sedentary behaviour, particularly television viewing, is obesogenic. Definitive evidence on dose–response relationships between physical activity, sedentary behaviour and obesity remain unclear. Dose–response evidence could be obtained fairly readily by intervention and longitudinal observational studies that use accelerometry in preschool children. The generalisability of much of the evidence base is limited and there is a need for research on the influence of physical activity and sedentary behaviour in the preschool years in the aetiology of obesity in the developing world.