Immigrants who have lived in the United States for at least 15 years are nearly as obese as U.S.-born adults, according to an article in the Dec. 15 issue of The Journal of the American Medical Association.
Immigrants generally originate from countries where the prevalence of obesity is lower than that of the United States, but acculturation to U.S. norms over time may lead to an increasing prevalence of obesity among this population, said the study’s lead author Mita Sanghavi Goel, M.D., a researcher in general internal medicine at Northwestern University Feinberg School of Medicine.
Immigrants also face more barriers to quality health care and are less likely to receive preventive health care than persons born in the United States, Goel said.
Goel and co-researchers from Harvard University also found that immigrants are less likely than U.S.-born people to discuss diet and exercise with their doctors.
Over 127 million American adults are overweight and almost 70 million are obese or severely obese. The high prevalence of obesity in the U.S. population has produced a major burden of obesity-related illness and death.
Immigrants are the fastest growing segment of Americans, comprising more than 11 percent of the total U.S. population.
The investigators surveyed almost 32,400 eligible people. About 14 percent were foreign born and generally older and had lower annual household incomes; less education; lower illness burden; and less access to good health care than U.S.-born respondents.
Fewer of the foreign-born respondents were obese compared with respondents born in the United States, but they were more sedentary than U.S.-born respondents.
The proportion of overweight and obese foreign-born individuals increased with longer residence in the United States.
After less than a year in the United States, the prevalence of obesity among foreign-born persons was 8 percent. In contrast, the body mass index of foreign-born respondents living in the United States for at least 15 years approached that of U.S.-born respondents, with 41 percent at normal weight, 38 percent overweight and 19 percent obese – compared with 41 percent, 35 percent and 22 percent of the U.S.-born, respectively.
The researchers found that body mass index did not increase substantially until after the foreign-born respondents had lived in the United States for at least 10 years, suggesting a threshold effect.
About 18 percent of foreign-born respondents reported discussing diet and eating habits with a health care provider compared with 24 percent of U.S.-born respondents.
This finding suggests that clinicians may be paying less attention to diet and exercise among some immigrant groups, Goel said.
With the growing immigrant population in the United States, early clinical intervention on diet and physical activity may represent an important opportunity to prevent weight gain, obesity and obesity-related chronic illnesses, the authors said.
Worldwide, obesity (or “globesity,” as described by the World Health Organization) has become an epidemic, affecting over 300 million people, with a threefold increase since 1980 in some areas of Europe, the Middle East, Pacific Islands and China. Yet, the prevalence of obesity in most parts of the world is lower than that in the United States.
Goel’s co-authors were Ellen P. McCarthy, Russell S. Phillips, M.D., and Christina C. Wee, M.D., Harvard Medical School, Boston.
This research was supported by awards from the National Research Service; the Ryoichi Sasakawa Fund; the National Institute of Diabetes and Digestive and Kidney Diseases; the National Cancer Institute; and the National Institutes of Health.