摘要：Objectives. We used nationally representative longitudinal data from the Mexican Family Life Survey to determine whether recent migrants from Mexico to the United States are healthier than other Mexicans. Previous research has provided little scientific evidence that tests the “healthy migrant” hypothesis. Methods. Estimates were derived from logistic regressions of whether respondents moved to the United States between surveys in 2002 and 2005, by gender and urban versus rural residence. Covariates included physical health measurements, self-reported health, and education measured in 2002. Our primary sample comprised 6446 respondents aged 15 to 29 years. Results. Health significantly predicted subsequent migration among females and rural males. However, the associations were weak, few health indicators were statistically significant, and there was substantial variation in the estimates between males and females and between urban and rural dwellers. Conclusions. On the basis of recent data for Mexico, the largest source of migrants to the United States, we found generally weak support for the healthy migrant hypothesis. Questions about who does and who does not migrate to the United States remain fundamental and unresolved issues in immigration research. There is evidence that international migrants are not a random sample from their home countries. 1 – 3 Moreover, research suggests that most prime-aged migrants move in search of better labor market opportunities and, because they have the motivation and resources to undertake a move, they are “positively selected”—that is, they are more educated and in better psychological and physical health than are nonmigrants. 2 , 4 We used newly collected data to examine evidence for this “healthy migrant” hypothesis in the United States. The topic is of particular interest in the United States because studies have appealed to this type of selection process as a plausible explanation for the widely documented “Hispanic paradox.” The paradox refers to the mortality advantage of Hispanic adults relative to non-Hispanic Whites despite the lower socioeconomic status of Hispanics. 2 , 5 , 6 In spite of the popularity of the healthy migrant hypothesis, evidence for it is weak and conclusions about its importance in the United States are premature, at best. Because few studies of international migration contain information about migrants before they arrived in the United States or information about comparable nonmigrants, most have relied on comparisons between the native born and foreign born; in some cases, the latter group was restricted to legal immigrants. 7 – 10 These studies, which generally demonstrated that the foreign born were in better health than were natives, did not provide scientific evidence about the healthy migrant hypothesis for at least 3 reasons. 11 First, the appropriate comparison group to test the hypothesis is nonmigrants from the home country rather than natives in the United States. Second, previous studies have typically examined the health of migrants after they moved to the United States rather than prior to migrating. Third, most existing research relied on self-reports of health, information that has been shown to depend upon cultural factors, ethnicity, and access to health care. 12 Our study focused on recent migration from Mexico to the United States, a migration stream that accounts for about 30% of all immigrants to the United States and more than half of undocumented immigrants. 13 Our analysis was based on survey data collected in Mexico that were well suited to test the healthy migrant hypothesis.
