Children spend a large portion of their day in school. Because many of the lifestyle and behavior choices associated with obesity develop during school-age years, a child's food intake and physical activity at school are important determinants of body weight.1 By providing meals, physical activity, and health education, school policies can help to prevent childhood obesity.
More than 25 million students use the National School Lunch Program (NSLP) daily, while approximately 7 million utilize the National School Breakfast Program (NSBP) daily.2 Meals from these programs may constitute more than half the daily caloric intake for children who participate in both programs, particularly for those from low-income families. Because such children have a higher prevalence of obesity during their adolescent years than do those with higher socioeconomic status,1 the provision of free or discounted meals through these programs may influence food intake among this group.3
Currently, however, total and saturated fat contents of meals provided by most schools exceed the limits required by the NSLP and NSBP programs.4 Training of food preparation staff may effectively address this problem without decreasing student participation rates.5 Many schools also have snack bars, student stores, and vending machines that offer foods high in fat and sugar content. Students at schools that offer such food sources in addition to the NSLP are less likely to consume fruits, juice, and vegetables than students who are only offered the NSLP.6 Recognizing this problem, the California State Senate passed a bill last year placing nutrition regulations on all foods sold in public schools.7
School programs that encourage physical activity are important for increasing children's energy expenditure, because children are less likely to participate in physical activity in the absence of adult supervision.8 These programs may also create expectations for regular physical activity that may persist into adulthood. In order to increase physical activity among children regardless of their athletic abilities, the CDC recommends daily physical education classes that emphasize health-related fitness activities over activities requiring specific athletic abilities.9 However, in 2001 only half of high school students participated in physical education classes and less than one third of students had physical education daily.10 In addition to requiring physical education, other opportunities for schools to increase energy expenditure include encouraging physical activity during recess and providing after-school sports and health-related fitness programs.9
Schools also have the potential to influence students' beliefs and attitudes regarding nutrition and weight control. A 2001 national survey documented poor eating behaviors among American youth. Only 21.4% of high school students had eaten more than five servings per day of fruits and vegetables; 13.5 % reported fasting for more than 24 hours to lose weight; 9.2% reported using diet pills that were not prescribed by a physician; and 5.4% reported using vomiting or laxatives as a weight control measure.10 In another national survey, fat comprised an average of 35% of total caloric intake in youth aged 2 to 19 years, and almost two-thirds of these youth did not eat recommended amounts of fruits and vegetables.11 Nutrition education could give students the tools they need to make healthy choices regarding eating and physical activity. More research is needed to examine the effects of such education programs on behaviors and body weight.
Although schools could potentially have a large impact on determinants of obesity, results of studies examining school-based obesity interventions have been variable.11 A review of these studies found that strategies aimed at younger children had better long-term results than those focused on adolescents, which may suggest that eating and physical activity behaviors are more difficult to change as children get older.12 The variability of results in studies examining school-based interventions underscores the fact that many influences outside schools are important determinants of children's body weight. While childhood obesity may not be overcome by the efforts of the education system alone, schools provide an important opportunity for prevention.
Carter RC. The Impact of Public Schools on Childhood Obesity. JAMA. 2002;288(17):2180. doi:10.1001/jama.288.17.2180-JMS1106-6-1