The Prevalence of Obesity in Iran in Recent Decade; a Systematic Review and Meta-Analysis Study

Background: There is a great deal of descriptive studies on obesity in Iran, mostly assessed the prevalence and its relationship with various risk factors and chronic diseases. In order to obtain/give a better insight into the epidemiology of obesity in Iran in recent years and assess its heterogeneity around the country, we reviewed systematically all available studies and analyzed their findings using Meta-analysis. Methods: All published papers in Iranian and international journals, final reports of research projects, papers in relevant congresses, proceeding books and dissertations of students were reviewed. Those findings, which published between 1997 and 2007 and met eligible criteria, were entered in meta-analysis (Random Model). Results: Fifty eight eligible papers (out of 219) including 132864 individuals were entered into analysis. The overall prevalence of obesity for adults (>18 yr) and children (<18y) was 21.5% (CI95% 17.4-25.6) and 5.5% (CI95% 4.5-6.4), respectively. The prevalence of obesity in boys and girls (<18y) was 5.3% (CI95% 4.1-6.4) and 4.8% (CI95% 4.0-5.7), respectively. It increased in both adult men and women to 13.7% (CI95% 10.9-16.7) and 27.3% (CI95% 21.3-33.4), respectively. Meta regression indicated that only age explained a considerable proportion of the observed heterogeneity among women. Conclusion: In overall, the risk of obesity was greater in women, but even in adults, the prevalence was less than that in developed countries. The percentage of obesity was increased by aging, especially in women. There were large variations in the reported prevalence of obesity in Iran; it is mainly because of the different in the distributions of age and sex among the subjects.