The prevalence of overweight among young people has increased dramatically. Between 1980 and 1994, children and adolescents considered to be overweight (BMI-for-age > 95th percentile) increased by 100% in the United States. Thirteen percent of children age 6-11 and 14 percent of adolescents age 12-19 are estimated to be overweight (National Center for Health Statistics, 2001). Previous data showed that approximately 11 percent of children and adolescents aged 6-17 were overweight (Troiano and Flegal, 1998). Overweight youth are more likely to be overweight as adults, and they are more likely to have medical risks associated with cardiovascular disease than are other children and adolescents (Whitaker et al., 1997; Freedman et al., 1999).