摘要：Objectives. We examined the relationship between fast-food restaurants near schools and obesity among middle and high school students in California. Methods. We used geocoded data (obtained from the 2002–2005 California Healthy Kids Survey) on over 500 000 youths and multivariate regression models to estimate associations between adolescent obesity and proximity of fast-food restaurants to schools. Results. We found that students with fast-food restaurants near (within one half mile of) their schools (1) consumed fewer servings of fruits and vegetables, (2) consumed more servings of soda, and (3) were more likely to be overweight (odds ratio [OR] = 1.06; 95% confidence interval [CI] = 1.02, 1.10) or obese (OR = 1.07; 95% CI = 1.02, 1.12) than were youths whose schools were not near fast-food restaurants, after we controlled for student- and school-level characteristics. The result was unique to eating at fast-food restaurants (compared with other nearby establishments) and was not observed for another risky behavior (smoking). Conclusions. Exposure to poor-quality food environments has important effects on adolescent eating patterns and overweight. Policy interventions limiting the proximity of fast-food restaurants to schools could help reduce adolescent obesity. The marketing of food to children is in the national spotlight as rates of childhood obesity rise in the United States. More than 9 million US children and adolescents are obese, and just as many are at risk of becoming obese. 1 The consequential health risks include asthma, hypertension, type 2 diabetes, cardiovascular disease, and depression. 2 Fast food consumption by 2- to 18-year-olds increased 5-fold from 1977 to 1995; by the latter year, fast food was consumed at 9% of eating occasions and comprised 12% of daily caloric intake. 3 Almost one third of all youths now eat at fast-food restaurants on any given day. 4 One study reports that weekly consumption of fast food by young adults is directly associated with a 0.2-unit increase in body mass index (BMI). 5 Despite the possibility that proximity of fast-food restaurants to schools affects children's health, research has not yielded consensus on this issue. Multiple studies have found that fast-food restaurants are systematically concentrated within a short walking distance of schools, giving children greater access to low-quality food, but these studies do not make an explicit connection between proximity to fast-food restaurants and diet-related outcomes. 6 , 7 Studies that have examined possible associations between the density of fast-food outlets and outcomes such as food consumption and weight status among youths have not found a relationship. 8 , 9 Our study revisits these questions using new detailed data on youths in California.
