Lipoprotein metabolism, insulin resistance, and adipocytokine levels in Japanese female adolescents with a normal body mass index and high body fat mass.

Background: The prevalence of obesity is gradually increasing in Japan, but in women aged in their 20 s to 50 s it has been disproportionately decreasing. However, the exact body composition of this subset of the population has not been elucidated.
Methods and Results: Body composition was determined using whole-body dual energy X-ray absorptiometry and metabolic parameters in 157 Japanese female university students (21.1+/-1.9 years); 31 women had a normal body mass index (BMI), but an increased body fat mass (BFM). Only the 31 had significantly higher low-density lipoprotein-cholesterol levels (90.5 vs 99.0 mg/dl, P<0.01) and leptin concentration (7.0 vs 4.6 ng/ml, P<0.05) and lower high-density lipoprotein-cholesterol (80.4+/-15.1 vs 73.5+/-14.5 mg/dl, P<0.01) than females with normal BMI and normal BFM.
Conclusions: A considerable number of young Japanese women with a normal BMI have excess BFM and relatively higher lipid and leptin levels. These findings may provide an important basis for future epidemiological surveys and studies.