Effect of an Environmental School‐Based Obesity Prevention Program on Changes in Body Fat and Body Weight: A Randomized Trial

Abstract

This study tested the efficacy of two school-based programs for prevention of body weight/fat gain in comparison to a control group, in all participants and in overweight children. The Louisiana (LA) Health study utilized a longitudinal, cluster randomized 3-arm controlled design, with 28 months of follow-up. Children (N=2060; M age = 10.5 years, SD = 1.2) from rural communities in Grades 4 to 6 participated in the study. 17 school clusters (M = 123 children/cluster) were randomly assigned to one of three prevention arms: 1) Primary Prevention (PP), an environmental modification program, 2) Primary + Secondary Prevention (PP+SP), the environmental program with an added classroom and internet education component, or 3) Control (C). Primary outcomes were changes in percent body fat and body mass index z scores. Secondary outcomes were changes in behaviors related to energy balance. Comparisons of PP, PP+SP, and C on changes in body fat and BMI z scores found no differences. PP and PP+SP study arms were combined to create an environmental modification arm (EM). Relative to C, EM decreased body fat for boys (−1.7% ± 0.38% versus −0.14% ± 0.69%) and attenuated fat gain for girls (2.9% ± 0.22% versus 3.93% ± 0.37%), but standardized effect sizes were relatively small (< 0.30). In conclusion, this school-based environmental modification programs had modest beneficial effects on changes in percent body fat. Addition of a classroom/internet program to the environmental program did not enhance weight/fat gain prevention, but did impact physical activity and social support in overweight children.

Measuring food intake with digital photography

“…For example, the effect of interventions or second servings on the food intake of elementary school children in school cafeterias has been demonstrated in a number of studies that relied on the Digital Photography of Foods Method (Martin et al, 2007, Williamson et al, 2012, Williamson et al, 2007) and the method has been used to quantify the food intake behavior of preschool-age children in HS and their homes (Nicklas et al, submitted for publication-b). Further, this method has been used to objectively determine if food provision and intake in school cafeterias (Martin et al, 2010) and HS Centers (Nicklas et al, submitted for publication-a) meets national guidelines, and this information can be used to inform policy decisions.…”

Beyond the “I” in the Obesity Epidemic: A Review of Social Relational and Network Interventions on Obesity

“…While intraindividual factors, including beliefs, knowledge, and skills, are important aspects in the behaviour change process, interventions which are limited to targeting change at an individual level fail to address the importance of broader social, physical, economic and political contexts. The breakdown of study types by social ecological level was shown to be pyramid-shaped with the vast majority of studies focused on the individual [22, 24–27, 33, 34, 36–45, 48, 49] and a few interventions that included components which spanned into the interpersonal [23, 28, 30, 31, 35, 46, 47] or organizational realms [21, 29, 50]. Within organizational realms, interventions tended to target making nutritional or physical activity resources available.…”

“…For example, in a school setting, playgrounds and school yards were made accessible for children to play after end of curricular program, and school canteens were obliged to have fresh fruit and freshly made juices [32]. Another study program modified the cafeteria food service program (the contents of vending machines), and physical education programs [50] and another intervention included implementing short PA breaks during lessons [21]. …”

Weighing the Evidence of Common Beliefs in Obesity Research

“…It was unclear whether the relationships seen in this age group would apply to older children. However, a recent follow-up re-evaluating outcomes when the children were in fifth grade identified a “relatively small” effect on body fat effect and only in boys 97,99-101 . Given the known decrease in body fat that occurs in boys with proximity to puberty an effect of PE on obesity is difficult to decipher.…”