Preventing Childhood Overweight and Obesity

The longer-term benefits of limiting obesity rates in children are likely to be particularly important if the obesity persists into adult life. The persistence of excess weight in childhood into adult obesity appears to increase linearly with age from around 6 years and is particularly strong in adolescents (39). Parsons et al. (105) in their systematic review of childhood predictors of adult obesity found a range of factors including higher birth weight and earlier pubertal maturation consistently related to a greater risk of adult obesity. The issue of birth weights has already been addressed, but the causes of earlier pubertal maturation are more difficult to establish. Rapid early growth induced by high-protein and high energy-dense diets rich in fats and sugars may promote earlier maturation, but individual genetically related susceptibility to early puberty may also be involved. The review did not find a consistent relationship between physical activity or diet and childhood or adult obesity, but measures of habitual diet and activity are difficult to obtain accurately. The Amsterdam Growth and Health Longitudinal Study has suggested that high physical activities and lower protein intakes in adolescence were associated with lower fat masses and lower BMIs (106), but there are no known analyses of preventive initiatives that have focused specifically on reducing either total energy or protein intakes as a means of reducing adolescent obesity.

A recent Cochrane systematic review examined studies relating to the prevention of obesity in children and could only find seven trials that met their requirements (107). The review had intended originally to include only studies which lasted at least a year, but only three longer-term trials were found, and thus four short-term studies with a follow-up of at least 3 months were also included. Of these seven studies, two assessed physical activity interventions, one assessed reduction in sedentary behaviors, three assessed combined diet and physical activity interventions, and one involved a dietary intervention only. Although many of these studies produced promising results, the reviewers concluded that there are limited quality data on the effectiveness of obesity prevention programs, and no generalizable conclusion could be drawn.

A recent systematic review sponsored by CDC examined community interventions in a range of different settings that aimed to increase physical activity (108). This review screened 6238 potential titles, assessed 849 abstracts and specialist reports, and reviewed 253 trials in detail and found firm evidence to recommend only six interventions, although many other approaches showed potential. The recommended list included a mix of educational, behavioral, and social approaches and environmental and policy change (see Table 4).

School-based physical education was one of the approaches strongly recommended by the review, and although the focus of the review was not weight control, nine of the 14 studies reviewed in this area examined markers of body weight/fatness as outcomes. These studies are presented in Table 5. The interventions involved changes in the way physical education classes were taught within a school setting, but additional policies involving comprehensive daily physical education were also assessed. The comparison groups usually received simply standard health education or changes in the physical education curriculum. The reviewers noted that physical education classes in schools usually

Table 4 Recommendations from the CDC Review of Interventions to Increase Physical Activity



Informational approaches to increasing physical activity Communitywide campaigns

''Point-of-decision'' prompts to encourage stair use Classroom-based health education focused on providing information Mass media campaigns Behavioral and social approaches to increasing physical activity School-based physical education (PE) Social support interventions in community settings Individually adapted health behavior change programs Classroom-based health education focused on reducing television viewing and video game playing College-age health education and PE Family-based social support Environmental and policy approaches to increasing physical activity Creation of or enhanced access to places for physical activity combined with informational outreach activities

Strongly recommended Recommended Insufficient evidencea Insufficient evidencea

Strongly recommended Strongly recommended Strongly recommended Insufficient evidencea

Insufficient evidencea Insufficient evidencea

Strongly recommended a A determination that evidence is insufficient should not be confused with evidence of ineffectiveness. A determination of insufficient evidence assists in identifying (1) areas of uncertainty regarding an intervention's effectiveness, and (2) gaps in the evidence where future prevention research is needed. In contrast, evidence of ineffectiveness leads to a recommendation that the intervention not be used. Source: Ref. 105.

Table 5 Controlled Trials of School-Based Physical Education BMI (10 arms; 10 measures)

Net intervention

Net intervention

Table 5 Controlled Trials of School-Based Physical Education BMI (10 arms; 10 measures)

Study (Ref.)








CATCH, 1996

Diet Tweak System

Diet Tweak System

Trying To Lose Weight Can Be Tough. But... Not Losing Weight and Gaining What You Lost Back, Sucks. If you've ever felt that no matter what you do to lose weight nothing seems to work. If you've ever felt that there has got to be some kind of a system or way to lose weight...but just have not found it yet.

Get My Free Ebook

Post a comment