The study by the Institute for Health Metrics and Evaluation (IHME) found that life expectancy in the U.S. varies significantly from county to county. In the case of Los Angeles County in California, that area has one of the highest life expectancies in the country despite a poverty rate above the national average. Researchers believe that the reason for this could be the “Hispanic paradox”, a phenomena found in previous studies over the past several decades including a 2010 Centers for Disease Control report. The idea is that Latinos live longer than those in other ethnic categories despite facing adverse socioeconomic factors (e.g. lower education, high indices of diabetes and obesity).
According to the Los Angeles Times there are several possibilities explaining how the paradox can be seen in the IHME study:
Nearly half of Los Angeles County's 10 million residents are Latino, and more than a third are foreign born, according to census data. By contrast, less than a sixth of the population nationally is Latino, and less than an eighth is foreign born.People in several developing countries have more longevity than some U.S. counties based on the report. Women in five Mississippi counties have life expectancies below 74.5 years, which is lower than Honduras, El Salvador, and Peru.
One explanation of that phenomenon is that the people who become immigrants tend to be healthy. "These are not random people. They are the healthiest people who could get here," said Carmen Nevarez, former president of the American Public Health Assn.
But David Hayes-Bautista, who heads the Center for the Study of Latino Health and Culture at UCLA, said other factors, including social support networks, diet and even physical labor, may play a role as well, because not all immigrants have such good health outcomes as Latinos.
Online Sources- Los Angeles Times, ABC News, Wikipedia, HispanicBusiness.com, Institute for Health Metrics and Evaluation