“The Hispanic Paradox” has long puzzled demographers and sociologists. It holds that foreign-born Hispanics in the United States live longer than their native-born counterparts despite having lower average income and education.

Andrew Fenelon, a joint Ph.D. student in demography and sociology in the School of Arts and Sciences, says he can explain the phenomenon in two words: cigarette smoking.  

Fenelon and his co-author, Laura Blue, a graduate student at Princeton University, found in their report—“Explaining Low Mortality Among US Immigrants Relative to Native-born Americans: The Role of Smoking,” published earlier this year in the American Journal of Epidemiology—that low death rates from smoking is the main reason that immigrants and Hispanics have a longer life expectancy in the United States.  

Fenelon says his study, funded by the National Institutes of Health, is the first to calculate the contribution of smoking to U.S. mortality disparities.

The study concludes that smoking explains more than half of the difference in life expectancy at 50 years of age between foreign-born U.S. residents and native-born Americans, and close to three-quarters of the difference in life expectancy between Hispanics and non-Hispanic whites.

Fenelon says prior research shows that Hispanic women on average live 83 years, compared to 80 years among non-Hispanic white women. Life expectancy for Hispanic men is nearly 80 years, two years longer than non-Hispanic white men. Hispanics also outlive African Americans by more than seven-and-a-half years.

“The factors that lead to poor health among those with low socioeconomic status do not seem to affect Hispanics in the U.S.,” Fenelon says. “Smoking may be key to understanding this unexpected finding.” He reports that Hispanic immigrants are less likely to smoke at all, and Hispanic smokers consume fewer cigarettes on average than native-born Americans.

“Smoking is rare and light among Mexican immigrants to the U.S. and Mexicans in Mexico,” he says. “Findings are similar for other large [immigrant] sending countries in Central and South America. Low rates of smoking reflect the societies where Hispanic immigrants originate, and is a behavior retained even after those migrants come to the U.S.”

Previous studies have documented a lower smoking prevalence among American immigrants compared with native-born Americans, and among Hispanics compared with non-Hispanic whites.