Waist-To-Height Ratio, Lean Mass and Fat Mass in Preschool Children

Introduction: Abdominal fat and the proportion of lean body mass have both been independently considered as risk factors leading to insulin resistance and to an increased risk of developing chronic diseases later in life. Objective: To analyse the relationship between the waist-to-height ratio (WHtR) and other body composition indicators in children aged 2-6 years at public childcare centres. Methods: This study consisted of a random, probabilistic cluster sampling of 9 of the 59 existing childcare centres (Taubate-SP, Brazil), resulting in the evaluation of 950 preschool children. The body mass index z-score (zBMI) and internationally accepted cut-off points were used to evaluate their nutritional status. The z-score for the arm muscle area (zAMA) and arm fat area (zAFA) and the WHtR were used to evaluate their body composition. Analyses were performed using the parameters of central tendency, dispersion, proportions and correlations, adopting a significance level of 5%. Results: The data indicated a direct correlation between the WHtR and zBMI (r P = 0.78), zAMA (r P = 0.52), zAFA (r P = 0.66) and the percentage of AFA (r P =0.54), with p <0.0001. There was an inverse correlation between the WHtR and the percentage of AMA (r P = -0.54), with p <0.0001. Conclusion: In preschool children, as the WHtR increases, the amounts of both lean body mass and body fat mass also increase. However, an increase in the waist circumference is accompanied by a disproportionately greater increase in fat mass compared to lean mass, which could indicate an additional risk factor for future chronic diseases.