second- and third-generation adolescents of U.S. immigrant families, especially Asian-American and Hispanic/Latino adolescents born in the United States, are twice as likely to be obese than the first-generation residents (Popkin and Udry, 1998). In another study, acculturation to the United States was identified as a risk factor for obesity-related behaviors, such as increased television viewing and higher levels of consumption of energy-dense and low-nutrient foods among Asian-American and Hispanic/Latino adolescents (Unger et al., 2004).
The disparities in the rates of obesity for Hispanic/Latino adolescents have been attributed to environmental, contextual, biological, and sociocultural factors, in addition to differences in income and education (NRC, 2006a,b). The families of foreign-born immigrant youth are more likely to have both lower family incomes and mothers with lower levels of education. They are also more likely than their American-born counterparts to live in communities with higher densities of immigrants and greater linguistic isolation (Gordon-Larsen et al., 2003). Additionally, children from immigrant families have more compromised physical health than children from nonimmigrant families and use health care services less frequently (Huang et al., 2006).
The deleterious effects of acculturation among Hispanic/Latino youth suggests that this ethnic population will be increasingly burdened by the complications of obesity, and the U.S. health care system will be faced with larger numbers of Hispanics/Latinos experiencing chronic diseases and their complications (NRC, 2006a).
These trends for immigrant youth parallel the observations for immigrant adults. Among the different immigrant subgroups, the number of years of residence in the United States is associated with higher BMI levels after 10 years, and the prevalence of obesity among immigrants who have lived in the United States for at least 15 years has been found to approach that of American-born adults (Goel et al., 2004).
Health disparities are commonly defined as the population-specific differences in the presence of disease, health outcomes, or access to health care among racial, ethnic, and SES groups (Chen et al., 2006; Lavizzo-Mourey et al., 2005; Yancy et al., 2005). Because of the complexity of identifying, measuring, and monitoring health status and health determinants, it is challenging to reach a consensus about the dimensions of health disparities. Complicated relationships and interactions among race, ethnicity, gender, income, education, degree of acculturation, immigrant status, and place of residence have an impact on health disparities and health outcomes (IOM, 2006). Additionally, the lack of complete and accurate data examining