Developmental Stage-dependent Influence of Environmental Factors on Growth of Rural Sundanese Children in West Java, Indonesia Makiko Sekiyama, 1 * Katrin Roosita, 2 and Ryutaro Ohtsuka 3 1 Graduate Program in Sustainability Science (GPSS), Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa City 277-8563, Japan 2 Department of Community Nutrition, Faculty of Human Ecology, Bogor Agricultural University, Bogor, Indonesia 16680 3 Japan Wildlife Research Center, Tokyo 130-8606, Japan KEY WORDS child growth; IGF-I; IGFBP-3; dietary intake; anemia; helminthiasis; Indonesia ABSTRACT This study investigated the growth tra- jectories and the relative relevance levels of nutrition, disease, and hormonal status at various developmental stages among children in adverse environments to pro- vide population-based empirical evidence for the life his- tory theory. Three years of longitudinal anthropometric data in 1-year intervals were obtained from 418 boys and girls aged 0 to 12 years at recruitment. Following the final measurement, the main survey, which included blood and feces sampling, 3-h interval food consumption recall surveys for energy and nutrient intakes and anthropometry, was performed. Blood and feces were used for detecting, respectively, anemia and hormonal (IGF-I and IGFBP-3) levels as well as intestinal helmin- thiasis (Ascaris, Trichuris, and hookworm). The major findings of this study are summarized as follows: 1) the growth velocity of the subject children lagged behind international standards during childhood and juvenility but caught up during early adolescence; 2) diseases, both intestinal helminths and anemia, had significant effects on growth in childhood but not at older ages; and 3) hormonal status significantly affected growth in the children, with its highest significance in early adoles- cence. A larger growth than international standards in early adolescence likely follows programmed hormonal mechanisms after the onset of puberty. The onset of puberty might be associated with adequate amounts of nutrient intake and be mediated by hormonal function, because the IGF-IZ score was significantly correlated with energy and protein intakes at the transitional period from juvenility to adolescence, when puberty occurs. Am J Phys Anthropol 157:94–106, 2015. V C 2015 Wiley Periodicals, Inc. Human growth, compared with the growth of nonhu- man primates, is characterized by a prolonged growth period before adulthood with inserted periods of child- hood and adolescence and an extended period of juvenil- ity. According to Bogin’s definition of the stages in the human life cycle (1999), childhood is defined as the period from the end of lactation to the 7th year, followed by a juvenile period. Puberty occurs at the end of the juvenile period at approximately the 9th year for girls and 11th year for boys, and adolescence is the approxi- mately 5- to 8-year period after puberty. Insertion of the childhood phase allowed for shorter breastfeeding dura- tions and interbirth intervals, increasing human fertility relative to nonhuman primates (Bogin, 1999, 2009; Leigh, 2001; Gurven and Walker, 2006). Furthermore, during the childhood period, children experience a wide range of environmental changes and acquire immunity to various antigens, which improves the survival rate to reproductive age. These environmental changes include seasonal variations in temperature and rainfall, years of food abundance and shortage, and changes in types of disease (Bogin, 1999; McDade, 2003). The extended juve- nile and adolescent periods provide time to practice the complex social skills required for effective parenting (Bogin, 1999). Life history theory provides a comparative evolution- ary framework for understanding developmental and reproductive strategies, assuming that resources are lim- ited and that energy is allocated to three primary life functions: growth, reproduction, and maintenance (McDade, 2003). The immune system is an essential component of maintenance efforts, and from birth to the juvenile period, resources are allocated into either growth or maintenance because reproductive effort is negligible (McDade, 2003). Children in nutritionally and epidemiologically privileged environments would have sufficient fuel for growth as well as effective immune response to infection, whereas children in an adverse environment would exhibit high allocation competition, resulting in poor growth and impaired immunity (McDade et al., 2008). During adolescence, reproductive effort increases dramatically, and resources are allocated Grant sponsor: Japan Society for the Promotion of Science (JSPS) Core University Program between The University of Tokyo and Bogor Agricultural University. *Correspondence to: Makiko Sekiyama, Graduate Program in Sustainability Science (GPSS), Graduate School of Frontier Scien- ces, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa City, 277-8563, Japan. E-mail: sekiyama@k.u-tokyo.ac.jp Received 22 July 2014; revised 11 December 2014; accepted 12 December 2014 DOI: 10.1002/ajpa.22692 Published online 12 January 2015 in Wiley Online Library (wileyonlinelibrary.com). Ó 2015 WILEY PERIODICALS, INC. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 157:94–106 (2015)