Socio-demographic and cultural comparison of overweight and obesity risk and prevalence in adolescents in Southern California and Wuhan, China.

PURPOSE

This study performed parallel analyses on two large samples of seventh graders living in Los Angeles, California and in Wuhan, China to make direct comparisons of overweight and obesity risks in Western and Eastern cultural environments.

METHODS

Two representative samples of 1772 and 1896 seventh grade students were randomly selected from the public or parochial middle schools in the greater Los Angeles area of Southern California in the United States, and public schools in Wuhan city of China. Two body mass index (BMI) references recently established by the U.S. National Center for Health Statistics (NCHS) and the International Obesity Task Force (IOTF), respectively, were used to define overweight (85th < or = BMI < 95th percentile) and obesity (BMI > or = 95th percentile). Logistic regressions were conducted to examine relationships between socioeconomic status (SES) and obesity risk.

RESULTS

The prevalence rates of combined overweight and obesity in Los Angeles and in Wuhan were 43.1% and 12.1%, respectively, by the US-NCHS reference, and 45.8% and 11.9%, respectively, by the IOTF reference. Chinese-American adolescents had higher prevalence rates for overweight and obesity than those from China. SES was positively related to the risk of overweight and obesity in the Chinese sample, whereas a negative association was found in Southern California adolescents. Urbanicity was significantly positively related to higher overweight and obesity prevalence.

CONCLUSION

Different overweight and obesity prevalence estimates and SES effects were observed for American and Chinese adolescent samples. Research on the underlying mechanisms is needed to help us to set up a tailored program for obesity prevention in Eastern and Western cultural environments.