Iranian Journal of

Background: A unique subset of Individuals with normal body mass index (BMI= 18.5-24.9 kg/m2) and high body fat percentage (above 30% in women and 23% in men) that are termed as normal weight obese, are at increased risk for development of the metabolic syndrome and chronic diseases because the adipose mass and the excess of fat mass are an important source of proinflammatory cytokines. The aim of the present study was based on this hypothesis that women with high body fat percentage and normal body mass index are at increased risk for the metabolic syndrome in compared to healthy non obese women. Methods: This was as case-control study in which 40 obese women with normal weight (BMI= 18.5-24.9 kg/m2) and body fat percentage above 30% (FM> 30%) and 30 non-normal weight obese women (BMI= 18.5-24.9 kg/m2) and fat percentage less than 25% (FM <25%) who were matched for age (mean age = 28 years) recruited for this study. The components of metabolic syndrome including Anthropometric variables, blood pressure and fasting plasma concentrations of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, glucose and insulin were measured. Results: The anthropometric measurements including waist and hip circumferences in NWO was higher than non-NWO (respectively 74.78±4.81 vs. 70.76±2.91 and 99.12±4.32 versus 93.16±2/91, Pvalue<0.001), while the waist-to-hip ratio did not differ between the two groups (p=0.448).Also no significant differences were observed in concentrations of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, fasting plasma glucose, systolic and diastolic pressure between groups. Fasting serum insulin and insulin resistance was higher in NOW compared to non NWO (Pvalue<0.05) and insulin sensitivity in NWO was lower than non NWO (0.357 versus 0.374, pvalue = 0.043). Conclusion: Because of the higher serum insulin concentration and the lower insulin sensitivity, obese women with normal body mass index but high body fat percentage can be associated with a higher risk for metabolic dysregulation and metabolic syndrome compared to healthy women with the same body mass index and normal body fat percentage