Objectives: The aim of this study was to evaluate the differences of obesity rate among three ethnic groups in northern adults in IR Iran in 2010.

Methods: The present cross-sectional, analytical study was conducted on 2994 cases of the same age and sex in three ethnic proportions (Fars-native=1625, Turkman=977, and Sisstani=392). The subjects aged between 15 and 65 years old and were selected by multistage cluster sampling techniques including 150 clusters each containing 20 subjects in urban and rural areas in 11 districts in Golestan province (northern IR Iran). Obesity was defined after WHO classification by BMI (Body Mass Index) equal or over 30 kg/m2. SPSS 16.0 software was used for statistical analysis and P value<0.05 was considered as statistically significant.

Results: Mean±SD of BMI in Fars-native, Turkman, and Sisstanish ethnic groups was 26.72±5.56, 26.18±5.34, and 24.59±6.72 kg/m2, respectively. Averagely, obesity was common in 22.8% of the subjects and was significantly higher among the females compared to males (32.3% vs13.3%) (P=0.001). Also, its prevalence was estimated as 25%, 22.6%, and 14% in Fars-native, Turkman, and Sisstanish ethnic groups, respectively. Statistical differences were significant among the three ethnic groups (P=0.001). The risk of obesity was 2.041 [95% CI, 1.502-2.722] in Fars-native and 1.781 [95% CI, 1.298-2.472] in Turkman groups compared to Sisstanish ethnic group.

Conclusions: Over one out of five adults in northern IR Iran suffer from obesity and an alarming rate was shown among the women. Among the three ethnic groups, the highest and the lowest rates were seen in Fars-native and Sisstanish ethnic groups, respectively.