Central Fat Accumulation Associated with Metabolic Risks beyond Total Fat in Normal BMI Chinese Adults

OBJECTIVE: To investigate the association of central fat with metabolic risks in normal BMI Chinese people. METHODS: Normal BMI subjects (18.5 ≤ BMI < 24, n = 520) aged 18-82 years were included. Blood pressure, triglycerides, high-density lipoprotein cholesterol and fasting plasma glucose were collected as metabolic risk factors. Dual-energy X-ray absorptiometry was used to measure total and central fat. Central fat was indicated as percent trunk fat (%TF) and android/gynoid fat ratio. Multiple adjusted regression models were applied to investigate the association of total and central fat with metabolic risk factors. The assessment values of these fat measures were further compared by receiver-operating characteristic (ROC) curves. RESULTS: Both total and central fat were correlated with metabolic risk factors. After adjusting for BMI, the significant association of percent body fat (%BF) with metabolic risks diminished, whereas %TF and android/gynoid fat ratio were still correlated. When BMI was replaced with %BF in the models, the results remained unchanged. ROC analysis showed the areas under the curve (AUCs) of total and central fat for at least two metabolic risk factors were comparable in men. However, in women, the AUCs of %TF and android/gynoid fat ratio were significantly greater than those of BMI, %BF and waist circumference. CONCLUSIONS: Central fat accumulation had a stronger association with metabolic risks than total fat in normal BMI Chinese adults, particularly in women. Central fat had more important implications in assessing 'metabolically obese' individuals among normal BMI subjects.