Race/Ethnicity, Nativity, and Trends in Body Mass Index among U.S. Adults

OBJECTIVE: The average body mass index (BMI) is rising even as the U.S. population grows increasingly diverse. We extend prior research by examining BMI trends in diverse groups including whites, blacks, Chinese, Filipinos, Asian Indians, Mexicans, Puerto Ricans, and Cubans who are U.S. born, recent immigrants, or long-term immigrants. METHODS: We pool cross-sectional data from the 1989 to 2011 waves of the National Health Interview Survey (N=989,273) and use linear regression models to examine trends in BMI among U.S. adults. RESULTS: Annual increases in BMI are greatest among U.S. born Puerto Ricans and Mexicans and slowest among foreign born Chinese. Among the U.S. born in 2011, Chinese adults have an average BMI below the threshold for overweight, whereas blacks, Mexicans, and Puerto Ricans have average BMIs in the obese range. Foreign born adults average lower BMIs than U.S. born adults in most race/ethnic groups, and nativity disparities generally widen over time. BMI increases across calendar periods rather than birth cohorts. CONCLUSION: Our results suggest that calendar period interventions may be particularly useful in reversing rising BMIs in the U.S. However, interventions must be tailored to different race/ethnic and nativity groups in order to reduce disparities in body mass.