Adiposity rather than BMI determines metabolic risk

BACKGROUND AND AIM: There is increasing evidence suggesting that WHO body mass index (BMI) cut-off values are outdated and should not be applied to different population. To overcome misclassifications, direct measurements of percentage body fat (PBF) would be a better tool for preobesity and obesity diagnosis. The aim of this study was to analyze the body composition in a adult population in Centre-South of Italy, by age and gender, and to verify the accordance between BMI and PBF cut-off points for health status classification. METHODS: The total subject pool cover a total of 4408 participants adults. A completed screening of anthropometry and body composition by Dual X-ray Absorptiometry, (DXA) was assessed on 3.258 subjects. RESULTS: Distributions and quantitative reliable estimates of PBF, total body fat and lean, according to gender and age are provided. The prevalence of "at risk" subjects (preobese and obese) was 69% and 85%, for men and women respectively, according to PBF cut-off points. The agreement of BMI and PBF categories resulted low for the total and male population, even scarce for female population (all P≤0.001). The false negative classification of BMI was stronger for women than men and for younger than older subjects. CONCLUSIONS: Screening for adiposity in subjects with a normal BMI could better identify those at higher risk for cardiometabolic disturbances and cardiovascular mortality. The herein used cut-offs points of PBF, by age and gender, may provide a useful reference in clinical settings and public health services, in particular for the Italian Caucasian population.