Salivary Leptin Level in Young Adult Males and its Association with Anthropometric Measurements, Fat Distribution and Muscle Mass

Aims: 1) To assess salivary leptin levels in normal-underweight versus overweight and obese healthy adult males aged 18-25 years old. 2) The relative contribution of anthropometric measurements, fat percentage, fat distribution (visceral versus subcutaneous) and total as well as regional muscle mass in arms, trunk and legs respectively in predicting salivary leptin levels. Methods: A total of 92 adult males were classified into two groups based on their body mass index (BMI): normal-underweight, BMI <24.9 kg/m2 (n=51); overweight-obese, BMI >25 kg/m2 (n=41). Anthropometric measurements such as BMI, waist circumference (WC), hip circumference (HC) and waist-hip ratio (WHR) were measured through standardised methods. Fat percentage, visceral fat level, subcutaneous fat and muscle mass (total and regional) were measured using Karada scan bioelectrical impedance method. Fasting saliva samples were collected and used for assessing salivary leptin concentrations using enzyme-linked immunosorbent assay. Results: Statistical analysis of the data showed a significant difference between the two groups in all of the parameters measured except height and salivary leptin levels. Multiple regression analysis showed that HC, WC and WHR were good predictors for salivary leptin levels in normal-underweight group. However, in the overweight-obese group, height was the most important independent variable that could predict salivary leptin levels as a dependent variable. Conclusions: Predictors for salivary leptin levels in adult healthy males are different in normal-underweight subjects from overweight-obese subjects. The most important predictor for salivary leptin levels is HC in normal weight subjects, while it is height in overweight and obese healthy adult males.