More Evidence Supporting The Fit Immigrant Hypothesis

I don't think that it is original to me, although I have a hard time sourcing it, but the "Fit Immigrant Hypothesis" a.k.a. the "Healthy Immigrant Effect" is that immigrants are, in almost all respects, more socio-economically and physically fit individuals than non-immigrants, relative to the source population and frequently, relative to the destination population. 

This is basically because you don't immigrate unless you are confident that you will succeed if you do so and have the drive to make a big change, which most people don't. Not everyone is accurate in evaluating their fitness, even in this high stakes context, but on average, they are more right than wrong.

The beginning of a new paper on the topic and its citation are as follows:

Hispanics in the United States tend to have lower household income, education, and health insurance coverage when compared to non-Hispanic Whites. Despite these economic disadvantages, paradoxically, Hispanics have displayed an equality with or even advantages over other minority groups and non-Hispanic Whites across a wide range of health outcomes. 

For example, in 2019, the Hispanic population had a life expectancy advantage of 3.0 years over the non-Hispanic White population and 7.1 years relative to the non-Hispanic Black population, despite having real household income that was 26 percent lower than non-Hispanic White households (Wilson 2020). Hispanic immigrants have also shown lower infant mortality rates and prevalence of mental illnesses. 

These stylized facts are collectively known as the “Hispanic health paradox.” This essay will provide an overview of the Hispanic health paradox literature. We will document different instances of the Hispanic health paradox across various measures: life expectancy at birth, infant mortality rate, death rates, causes of death, and morbidity. 

We will discuss the leading explanations of the Hispanic health paradox and possible ways for economists to contribute to this discussion. The origin of the Hispanic health paradox is often traced to the seminal paper by Markides and Hazuda (1980), in which the outperformance of Hispanics was deemed an “epidemiological paradox.” The authors found that Mexican Americans in southwest Texas had a lower infant mortality rate relative to other groups, including non-Hispanic Whites. Markides and Coreil (1986) reported the same phenomenon for life expectancy, mortality, disease-related health outcomes, and mental and functional health. In fact, the first 

Hispanic health advantage reported was observed for mental health among Mexican Americans (Karno and Edgerton 1969). Markides and Eschbach (2005) renamed these advantages the Hispanic paradox. In their discussion, they highlight the role of immigration in explaining the paradox, with the initial assumption that immigrants need to be healthy enough to endure the cost associated with immigration: travel, adaptation to new customs, new laws, and potentially with few resources or support available. 

The Hispanic health paradox is closely tied to the “healthy immigrant effect” (also known as the “healthy immigrant paradox”). The healthy immigrant effect is an observed time path in which the health of immigrants just after the migration is substantially better than that of comparable native-born people, but worsens with additional years in the new country. 

Stephen et al. (1994) were the first to identify this effect using the 1989 National Health Interview Survey, because this was the first time the survey incorporated the number of years lived in the country. Since then, various authors have identified this effect across numerous health outcomes.

José Fernandez, Mónica García-Pérez, and Sandra Orozco-Aleman, "Unraveling the Hispanic Health Paradox" 37(1) Journal of Economic Perspectives 145-168 (Winter 2023).