Ethnic differences in obesity among immigrants from developing countries, in Oslo, Norway

Objectives: To compare ethnic and gender differences in generalized and central obesity and to investigate whether these differences persisted after adjusting for socio-demographic and lifestyle factors. Design: In 2002, the population-based cross-sectional, Oslo Immigrant Health study was conducted. Subjects: A total of 7890 Oslo residents, born between 1942 and 1971 in Turkey, Iran, Pakistan, Sri Lanka and Vietnam, were invited and 3019 attended. Measurements: Participants completed a health questionnaire and attended a clinical screening that included height, weight, waist and hip measurements. Results: Generalized obesity (BMI >= 30kg/m(2)) was greatest among women from Turkey (51.0%) and least among men from Vietnam (2.7%). The highest proportions of central obesity (waist hip ratio (WHR)>= 0.85) were observed among women from Sri Lanka (54.3%) and Pakistan (52.4%). For any given value of BMI, Sri Lankans and Pakistanis had higher WHR compared to the other groups. Despite a high mean BMI, Turkish men (27.9kg/m(2)) and women (30.7kg/m(2)) did not have a corresponding high WHR. Ethnic differences in BMI, waist circumference and WHR persisted despite adjusting for socio-demographic and lifestyle factors. Conclusion: We found large differences in generalized and central obesity between immigrant groups from developing countries. Our data find high proportions of overweight and obese subjects from Pakistan and Turkey, but low proportions among those from Vietnam. Subjects from Sri Lanka and Pakistan had the highest WHR for any given value of BMI. Our findings, in light of the burgeoning obesity epidemic, warrant close monitoring of these groups.