Physical growth of the shuar: Height, Weight, and BMI references for an indigenous amazonian population

Abstract

Objectives Information concerning physical growth among small-scale populations remains limited, yet such data are critical to local health efforts and to foster basic understandings of human life history and variation in childhood development. Using a large dataset and robust modeling methods, this study aims to describe growth from birth to adulthood among the indigenous Shuar of Amazonian Ecuador. Methods Mixed-longitudinal measures of height, weight, and BMI were collected from Shuar participants (n = 2,463; age 0–29 years). Centile growth curves and tables were created for each anthropometric variable of interest using GAMLSS. Pseudo-velocity and LMS curves were generated to further investigate Shuar patterns of growth and to facilitate comparison with U.S. CDC and multinational WHO growth references. Results The Shuar are small throughout life and exhibit complex patterns of growth that differ substantially from those of international references. Similar to other Amazonians, Shuar growth in weight compares more favorably to references than growth in height, resulting in BMI curves that approximate international medians. Several additional characteristics of Shuar development are noteworthy, including large observed variation in body size early in life, significant infant growth faltering, extended male growth into adulthood, and a markedly early female pubertal growth spurt in height. Phenotypic plasticity and genetic selection in response to local environmental factors may explain many of these patterns. Conclusions Providing a detailed reference of growth for the Shuar and other Amazonian populations, this study possesses direct clinical application and affords valuable insight into childhood health and the ecology of human growth.

Immune function in Amazonian horticulturalists

“…Protein synthesis increases during an immune response, from about 3.5g to 6g of protein per day per kilogram of body weight, an estimated expense of 285 kcal/day (McDade, 2003). Tsimane and other Amazonians are of small stature relative to international standards and are relatively lean but not underweight (Gurven et al, 2012a; Urlacher et al, 2015). Past studies of Tsimane and of Shuar, an Ecuadorian forager-horticultural population, have shown trade-offs between immune response and growth rates in children (McDade et al, 2008; Blackwell et al, 2010), and associations between IgE and the height of adolescents and adults (Blackwell et al, 2010).…”

“…During growth, Amazonians also appear to prioritise weight gain over skeletal growth and height attainment (Blackwell et al, 2009; Stieglitz et al, 2015a), and they also seem to accumulate fat in central locations where it may be particularly important for fueling immune defenses (Urlacher et al, 2015). Tsimane also have high resting metabolic rates and total daily energy expenditures, as measured by doubly labeled water and respirometry (Gurven et al, 2016).…”

Heterogeneous effects of market integration on sub-adult body size and nutritional status among the Shuar of Amazonian Ecuador

“…Anthropometric measures of body size and nutritional status were obtained for all study participants from two previously described SHLHP sources (Blackwell et al, 2009; Urlacher et al, 2016). Data from 1,196 participants ( N = 587 females; age 2.5-16.5 years) were collected during a health diagnostic study conducted by FICSH and the hospital Pio XII in collaboration with the SHLHP between October 2005 and August 2006.…”

Weight, height and body mass index of children and adolescents living at moderate altitude in Colombia

“…19 Hence, the results observed underscore the diversity and difficulty of physical growth in challenging environments. 20 This highlights the importance of obtaining new descriptions of PG variables and BMI values among populations, particularly in school populations at moderate and high altitudes.…”