Background: Interests in the role of micronutrients in obesity and its associated complications are recently increasing. Although zinc is an essential element for the function of many proteins including enzymes, hormones and transcription factors related to energy metabolism, the correlation between zinc and obesity is not clear in human. The aim of this study was to evaluate the association of zinc concentration in hair with metabolic risk factors in Korean women.
Method: Women's healthcare center of cheil general hospital in Seoul, Korea recruited 198 female outpatients as study participants. Hair zinc level and metabolic risk factors were assessed by blood test, hair mineral analysis (TEI, America), and anthropometric measurements. Statistical analyses were done with pearson correlation analysis and logistic regression analysis.
Results: The mean values of age (43.9 ± 12.1 years), body mass index (25.0 ± 4.5 kg/㎡), and hair zinc concentration (16.7 ± 7.2 mg%) were identified. Hair zinc concentration was inversely related to body mass index, percent body fat, waist circumference, systolic and diastolic blood pressure, fasting insulin and HOMA-IR (P < 0.05, tested by pearson correlation analysis). Logistic regression analysis showed that low hair zinc concentration (≤ 12 mg% ) was associated with obesity (BMI ≥ 25 kg/㎡, OR = 2.4, CI = 1.045-5.511, R² = 0.032), hypertension (≥ 130/85 mmHg, OR = 2.7, CI = 1.084-6.835, R² = 0.044), hyperinsulinemia (≥ 14 uU/mL, OR = 3.3 CI = 1.338-7.990, R² = 0.059), insulin resistance (HOMA-IR ≥ 3.7, OR = 2.8, CI = 1.141-6.836, R² = 0.041) and metabolic syndrome (OR = 3.2, CI = 1.120-8.954, R² = 0.055)
Conclusions: Low hair zinc is closely associated with increasing metabolic risk factors for Korean women.

Keywords: Obesity, Metabolic syndrome, Zinc, Hair