Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

Challenging Myths of the Deficit Perspective: Honoring Children\u27s Literacy Resources

The article discusses the deficit perspective that often distorts teachers\u27 vision when interacting with children from marginalized communities. A deficit perspective attributes many children\u27s school failures to perceived deficits within the children, their families, and their cultures. In contrast, a transformational perspective identifies and values the rich cultural practices embedded in diverse communities. Also relevant is the concept of multiple literacies. As a practice affected by culture, literacy takes various forms, in and out of school: reading for pleasure, reading for information, reading silently or aloud with others, memorizing and reciting significant texts. Participating with families in their worlds and learning from them is key in understanding the wealth of knowledge in homes and communities. By reaching beyond taken-for-granted ways of teaching and learning in schools, deficit perspectives can be challenged. Schools can develop creative uses of time and energy so that teachers can be directly involved in children\u27s lives, attending religious or sports events, for example, or joining families for meals. These efforts can lead to broader visions of learning

Intentionality and Expertise: Learning from Observations of Children at Play in Multilingual, Multicultural Contexts

This article draws from three ethnographic studies of children playing sociodramatically in multilingual, multicultural contexts. Countering a deficit perspective that focuses on what children from nondominant cultures do not know, we use the concept of syncretism to illuminate children\u27s expertise and intentionality as they blend knowledge from multiple worlds to reinvent cultural practices and create new spaces for learning. Findings encourage educators to learn from the syncretic nature of children\u27s teaching and learning through play

Guest Editors’ Introduction: Syncretism and Syncretic Literacies

An introduction is presented in which the editors discuss various reports within the issue on topics including children\u27s syncretic interactions, bilingual, biliterate and bicultural abilities of children, and the use of the syncretic process in teaching

Guest Editors’ Introduction: Syncretism and Syncretic Literacies

An introduction is presented in which the editors discuss various reports within the issue on topics including children\u27s syncretic interactions, bilingual, biliterate and bicultural abilities of children, and the use of the syncretic process in teaching

We’ve Been Doing It Your Way Long Enough : Syncretism as a Critical Process

This article takes a new look at issues of marginalization and equity in literacy practice by focusing on the concept of syncretism and teachers’ creation of opportunities for young children to draw on knowledge from multiple worlds as, together, they construct new texts, contexts and practices. Recognizing that the strengths and needs of too many students from minoritized communities are not being met, this piece draws attention to the importance of teachers’ appreciation of syncretism as a powerful learning process for challenging discriminatory and exclusionary practices. Drawing on theories of syncretism, and critical and culturally relevant pedagogies, the authors introduce critical syncretism as a process in which teachers and children privilege traditions and practices typically marginalized in schools for the purpose of supporting achievement and broadening worldviews. The article provides examples from two primary-grade classrooms illustrating ways that the teachers made specific moves to change classroom power structures. Whereas White, middle-class, Standard English ways of knowing had been privileged by the school district’s choice of instructional materials and recommendations for teaching practice, the teachers’ new practices opened up possibilities for syncretism by embracing knowledge, languages, traditions and practices from students’ homes, communities and African heritage, as well as from school

We’ve Been Doing It Your Way Long Enough : Syncretism as a Critical Process

This article takes a new look at issues of marginalization and equity in literacy practice by focusing on the concept of syncretism and teachers’ creation of opportunities for young children to draw on knowledge from multiple worlds as, together, they construct new texts, contexts and practices. Recognizing that the strengths and needs of too many students from minoritized communities are not being met, this piece draws attention to the importance of teachers’ appreciation of syncretism as a powerful learning process for challenging discriminatory and exclusionary practices. Drawing on theories of syncretism, and critical and culturally relevant pedagogies, the authors introduce critical syncretism as a process in which teachers and children privilege traditions and practices typically marginalized in schools for the purpose of supporting achievement and broadening worldviews. The article provides examples from two primary-grade classrooms illustrating ways that the teachers made specific moves to change classroom power structures. Whereas White, middle-class, Standard English ways of knowing had been privileged by the school district’s choice of instructional materials and recommendations for teaching practice, the teachers’ new practices opened up possibilities for syncretism by embracing knowledge, languages, traditions and practices from students’ homes, communities and African heritage, as well as from school