Development and Tracking of Body Mass Index from Preschool Age into Adolescence in Rural South African Children: Ellisras Longitudinal Growth and Health Study

The purpose of this observational prospective cohort study was to investigate the development and tracking of body mass index (BMI) of Ellisras rural children from preschool age into late adolescence from the Ellisras Longitudinal Growth and Health Study. Heights and weights of children were measured according to the standard procedures recommended by the International Society for the Advancement of Kinanthropometry twice a year from 1996 to 2003. In total, 2,225 children—550 preschool and 1,675 primary school—aged 3-10 years (birth cohorts 1993 to 1986) were enrolled at baseline in 1996 and followed through out the eight-year periodic surveys. In 2003, 1,771 children—489 preschool and 1,282 primary school—were still in the study. The prevalence of overweight was significantly higher among girls (range 1.6-15.5%) compared to boys (range 0.3-4.9%) from age 9.1 years to 14.9 years. The prevalence of thinness (severe, moderate, and mild) ranged from 7.1% to 53.7% for preschool children and from 8.0% to 47.6% for primary school children. Both preschool and primary school children showed a significant association between the first measurements of BMI and the subsequent measurement which ranged from B=0.2 (95% confidence interval [CI] 0.1-0.4) to B=0.8 (95% CI 0.6-0.9) for preschool and B=0.2 (95% CI 0.1-0.3) to B=0.7 (95% CI 0.6-0.8) for primary children. A significant tracking of BMI during 4-12 years of life was more consistent for preschool children (B=0.6 (95% CI 0.6-0.7) and for primary school children (B=0.6 (95%CI 0.5-0.6). Investigation of nutritional intake and physical activity patterns will shed light on how healthy these children are and their lifestyle

Development and Tracking of Body Mass Index from Preschool Age into Adolescence in Rural South African Children: Ellisras Longitudinal Growth and Health Study

The purpose of this observational prospective cohort study was to investigate the development and tracking of body mass index (BMI) of Ellisras rural children from preschool age into late adolescence from the Ellisras Longitudinal Growth and Health Study. Heights and weights of children were measured according to the standard procedures recommended by the International Society for the Advancement of Kinanthropometry twice a year from 1996 to 2003. In total, 2,225 children-550 preschool and 1,675 primary school-aged 3-10 years (birth cohorts 1993 to 1986) were enrolled at baseline in 1996 and followed through out the eight-year periodic surveys. In 2003, 1,771 children-489 preschool and 1,282 pri- mary school-were still in the study. The prevalence of overweight was significantly higher among girls (range 1.6-15.5%) compared to boys (range 0.3-4.9%) from age 9.1 years to 14.9 years. The prevalence of thinness (severe, moderate, and mild) ranged from 7.1% to 53.7% for preschool children and from 8.0% to 47.6% for primary school children. Both preschool and primary school children showed a significant association between the first measurements of BMI and the subsequent measurement which ranged from B=0.2 (95% confidence interval [CI] 0.1-0.4) to B=0.8 (95% CI 0.6-0.9) for preschool and B=0.2 (95% CI 0.1-0.3) to B=0.7 (95% CI 0.6-0.8) for primary children. A significant tracking of BMI during 4-12 years of life was more consistent for preschool children (B=0.6 (95% CI 0.6-0.7) and for primary school children (B=0.6 (95%CI 0.5-0.6). Investigation of nutritional intake and physical activity patterns will shed light on how healthy these children are and their lifestyle

A century of trends in adult human height

Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5-22.7) and 16.5 cm (13.3-19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8-144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries

Prevalence of abdominal obesity among rural South African children over time: Ellisras Longitudinal Study

Early detection for increased abdominal fat may be crucial in early prevention of cardiovascular diseases. The purpose of the current study was to explore the development of abdominal obesity of Ellisras rural children aged 6 to 14 years over time. Height, waist and hip circumferences were measured twice, yearly from 1996 to 2003. In total, 2,225 children aged 3-10 years enrolled in 1996 at baseline and were followed up to the eighth year in periodic surveys. In 2003, 1,701 children were still in the study. General estimated equation was used to assess tracking of abdominal obesity in these children. The prevalence of abdominal obesity, based on waist-to-height ratio, was not statistically different among boys (0 – 6.2%) as compared to girls (0 – 5.0%) throughout the period of measurements. Waist-to-height ratio showed a significant (p < 0.05) tracking coefficient between the baseline measurements and the follow-up measurements with ß = 0.30 95%CI 0.51 – 0.55 for unadjusted and ß = 0.27 (95%CI 0.26 – 0.28) adjusted for age and sex. The prevalence of abdominal obesity showed a decreasing trend among Ellisras girls as they grew older. There was a significant tracking of abdominal obesity among Ellisras children. Investigations of dietary and physical activity habits can shed light on the lifestyles and health status of these children.Keywords: Abdominal obesity, African children, Waist-to-height ratio

Which anthropometric indices can best estimate obesity amongst Ellisras population from childhood to young adulthood? Ellisras Longitudinal Study

Abdominal and general obesity are considered to be predisposing factors for several cardiovascular diseases such as hypertension. This study examined the most appropriate anthropometric tool for estimating obesity among Ellisras population from childhood to young adulthood. Using a crosssectional design, the study measured the anthropometric characteristics of 10,811 (aged 3 -9 years) and 14,311 children (aged 10-16 years) as well as 770 young adults (aged 18- 29 years). Accuracy of the various obesity measures (general and abdominal obesity) was evaluated using Receiver Operating Characteristic (ROC) analysis. Females showed higher (51.3%) significant (p<0.05) prevalence of abdominal obesity compared to males (4.3%) at an older age. ROC analysis revealed waist circumference (WC) (Area under the ROC curve: AUC= 0.974) and waist to height ratio (WHtR) (AUC=1.000) as the most appropriate tools to classify abdominally obese subjects at an older age. All the central obesity indices significantly (p<0.001) predicted the risk of overall obesity, the best being WC and WHtR followed by waist-hip ratio (WHR) both when unadjusted (B=0.431-63.417) and adjusted (0.350-2.818) for age and gender. Appropriate anthropometric tools for measuring general and abdominal obesity among the population in this setting for children are WC and body mass index (BMI) and WHtR and WC for young adults.Keywords: Obesity, prevalence, children, young adults, anthropometry

Physical activity level in pediatric population: A comprehensive review

Physical activity (PA) is a key component in the maintenance and attainment of healthy, active, well-nourished and psycho-social well-being of a society. Hence, the reduction of sedentary lifestyle has featured in many countries as an important arm of policy designed to address childhood chronic diseases of lifestyle risk factors. The purpose of this study was to review childhood (aged 1-22 years) PA variation in six different continents using individual studies published in English during the first decade of the 21st century. A computerized literature search was carried out and sometimes individuals in the pediatric PA area were requested to send some of their recently published reports in the field. The results of different studies were often difficult to interpret and compare due to different methods of measuring PA, differences in the analysis, reporting of insufficient data and lack of consensus on the appropriate cut-offs. Boys were physically more active than girls in all the five continents. South America and Oceania showed a high level of physical activity among both boys and girls compared to other continents. Social intervention to improve safety, rebuilding of physical environment may help to build a healthy and active society. An alternative route would be to incorporate physical education in both public and private school curricula as a compulsory monitored subject.Keywords: Physical activity, Physical education, children, adolescents, chronic diseases of lifestyle, built environment

Body composition of normal and malnourished rural South African children aged 6-13 years: Ellisras Longitudinal Study

The aim of this study was to investigate the body composition of normal and malnourished children aged 3 to 11 years. A total of 2198 children aged 3 to 11 years who are part of the Ellisras Longitudinal Study were grouped into 2066 normal and 132 stunted and 2070 normal and 128 wasted children using –2 SD of NHANES cut off point. Body composition was evaluated using anthropometric variables (weight, height, triceps, subscapular, suprailiac, biceps skinfolds). The anthropometric variables were measured according to the protocol of the International Society for the Advancement of Kinanthropometry. Children were categorized by the age groups as defined by Deitz (1999) for the development of obesity in children. The study showed that percentage body fat was high for the stunted children in the infancy and adipose rebound period (16.8% and 15.3% of stunted children compare to 15.6 and 14.9% normal children respectively), while the normal children had high significant percentage body fat at the adolescence spurt (14.6% compared to 15.5%). Inversely, normal children had high percentage body fat compared to wasting children throughout the age category. The fact that stunted children exhibit high percentage body fat at an early stage may clearly depict that stunting at an early stage of this population may be associated with overweight. Further studies are required to look into the development of obesity among children in this rural population so as to combat this health epidemic at an early stage. Key words: Percentage body fat, malnutrition, obesity, rural South African children. (Af. J. Physical, Health Education, Recreation and Dance: 2003 9(2): 224-237

The relationship between BMI and dietary intake of primary school children from a rural area of South Africa: The Ellisras longitudinal study

Objectives: To investigate the relationship between dietary intake and BMI of primary school children from a rural area of South Africa cross-sectionally. Both under and over nutrition remain major health problems in South Africa. In rural areas, where especially undernutrition leads to child morbidity and mortality, determinants should be detected. Methods: Data was used from 825 children (421 boys, 404 girls), aged 6-12 years, participating in the Ellisras Longitudinal Growth study. Height and weight were measured in accordance with the protocol of the International Society for the Advancement of Kinanthropometry. Internationally recommended cut-off points for body mass index (BMI) were used. Dietary intake was measured using the 24 h recall method. In general, boys and girls from Ellisras had dietary intake levels lower than or according to dietary guidelines. Results: A singular linear regression model showed a significant association between monounsaturated fat and BMI. The multiple model demonstrated that total fat (B=0.05, CI: 0.019-0.082), monounsaturated fat (B=-0.093, CI: -0.160 to -0.026) and polyunsaturated fat (B=0.056, CI: 0.09-0.02) predict BMI. Conclusion: This study supports previous findings about BMI and dietary trends in rural areas of South Africa. Despite low fat intake of the subjects, this macronutrient appeared to predict BMI most strongly. More research is needed; however, to further examine how healthy their lifestyle is nowadays with respect to diet and into what extent the nutrition transition has reached this area. Am. J. Hum. Biol. 26:701-706, 2014. © 2014 Wiley Periodicals, Inc