Relevance of measuring body fat in children

Abstract

EDITORIALST he adverse health consequences associated with obesity are related to increase in body fat rather than body weight per se. Thus, it stands to logic that measuring body fat would be a better tool for identifying risk as compared to any indirect measures of adiposity. Accurate measurement of body fat can be done by various techniques like under-water weighing, dual energy X-ray absorptiometry (DEXA), bioelectric impedance, etc. In recent times, DEXA has emerged as a tool of choice for body composition studies. However, use of these methods is largely restricted to research settings because of their complexity and cost. In clinical setting, anthropometric measurements such as skin fold thickness, waist circumference, waist-stature or waist-hip ratio and various height and weight-based indices like body mass index (BMI) are the common tools used to assess adiposity and its related complications.Body mass index has been validated as a simple, low cost tool to assess body fatness for routine clinical evaluation in children and adolescents [1], and is found to be strongly correlated with adiposity [2]. Increasing BMI is also shown to be associated with higher risk of metabolic complications [3]. However, BMI criteria for obesity may not identify differences in body fat or their distribution [4]. Thus, BMI is an appropriate screening test to identify children requiring further evaluation and follow-up, though it may not be diagnostic of the level of adiposity. Attempts have been made to link percentage body fat (PBF) estimates derived by DEXA with BMI and describe PBF values associated with BMI classification of over-weight and obesity [1]. There are age-related and sex-related variations in PBF and thus a single PBF value may not be suitable for classifying children as over-weight or obese.As an ethnic group, Asians tend to have a smaller body size and a relative deficit of lean body mass as compared to Europeans/Americans. Thus, at an equivalent body mass index (BMI), there is a relative excess of body fat in Asians. They also tend to have a more central rather than peripheral distribution of fat. These differences in body composition are evident from childhood and become more pronounced during adolescence. Shaw, et al. [4] from UK demonstrated that from age of 5 years onwards, South Asian girls and boys have higher PBF as compared to the White or African Caribbean ethnic groups, the difference increasing with age. This relative excess of adipose tissue at a given BMI makes Asians more predisposed to metabolic complications like type 2 diabetes (T2DM), hypertension and dyslipidemia [5]. These disorders also tend to occur a lower BMI in Asians as compared to their Western counterparts [6]. Like the increase in body fat, the risk of metabolic complications also starts becoming evident from adolescence itself. In UK, the relative risk of developing T2DM in childhood is reported to be 14 times greater in South Asian than in White European children [7]. In another study from UK, children of South Asian origin ...

Obesity measured as percent body fat, relationship with body mass index, and percentile curves for Mexican pediatric population

“…The BMI obesity misclassification has been reported in Mexican and Asian populations, which presents lower mean heights than European population. Mexicans or Asians have higher body fat values for a given BMI when they are compared with Europeans [10,11]. Hence, directly measuring body fat becomes relevant to determine obesity.…”

Determining Skinfold Thickness through Artificial Neural Networks

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