|Effects of Improved Nutrition in Early Childhood : The institute of Nutrition of Central America and Panama (INCAP) Follow-up Study; Proceedings of an IDECG workshop, July 1990, Bellagio, Italy, Supplement of The Journal of Nutrition (International Dietary Energy Consultative Group - IDECG, 1994, 198 pages)|
|Nutritional supplementation during early childhood and bone mineralization during adolescence(¹,²)|
LAURA E. CAULFIELD,*3 JOHN H. HlMES AND JUAN A. RIVERA
*Division of Human Nutrition, The Johns Hopkins School of Hygiene and Public Health, Baltimore, MD 21205, Division of Epidemiology, University of Minnesota School of Public Health, Minneapolis, MN 55 454, Centro de Inuestigaciones en Salud Pública, Instituto Nacional de Salud Pública, 62508 Cuernavaca, Morelos, México¹ Presented in part at the Annual Meeting of the American Public Health Association, October 1990, New York, NY. Caulfield, L. E. & Himes, J. H. (1990) Nutritional supplementation during early childhood and bone mineralization during adolescence. Published as a supplement to The Journal of Nutrition. Guest editors for this supplemental publication were Reynaldo Martorell, The Rollins School of Public Health of Emory University, Atlanta, GA, and Nevin Scrimshaw, The United Nations University, Boston, MA.
² Supported partially by grants HD - 24684 and HD-22440 from the National Institutes of Health, Bethesda, MD, USA.
³ To whom correspondence should be addressed. Division of Human Nutrition, The Johns Hopkins School of Hygiene and Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205-2179. matic and maturational responses to supplementation (Himes 1978, Himes et al. 1990), a secondary objective was to determine if there is evidence of a long-term, bonespecific response to supplementation, beyond what may be expected from concurrent somatic responses in body size.
To assess the long-term impact of nutritional supplementation on bone mineralization during adolescence, we studied 356 Guatemalan adolescents who participated from birth to 7 y of age in a controlled supplementation trial. Bone mineralization of the distal radius was assessed using single photon absorptiometry. Children who consumed more cumulative energy from the supplement during childhood had greater bone mineral content, bone width and bone mineral density during adolescence than those who consumed less energy. The associations remained after controlling for each subject's age and gender, and for the type of supplement consumed, but became statistically nonsignificant after adjusting for weight and stature. Because intake of supplement also was associated positively with weight and stature during adolescence, it is concluded that supplementing malnourished children can have a demonstrable long-term impact on bone mineralization, but that the effects are probably not beyond those due to improvements in overall somatic growth associated with supplementation. J. Nutr. 125: 1104S-1110S, 1995.
INDEXING KEY WORDS:
· bone mineralization
Adult levels of bone mineralization are largely achieved during the first two decades of life (Garn and Wagner 1969, Newton-John and Morgan 1971). Consequently, there is considerable interest in identifying determinants of this process in childhood and adolescence. Malnutrition is associated with low levels of bone density, diminished cortical bone and delays in skeletal maturation (Himes 1978, Himes et al. 1975, Martorell et al. 1979). Dietary interventions can enhance bone mineralization and skeletal maturation in infants and children who are undernourished in the short-term (Gunmán et al. 1965, Himes et al. 1990,Martorell et al. 1979), but the long-term permanency of such improvements is unknown.
From 1969 to 1977, the Institute of Nutrition of Central America and Panama (INCAP) conducted a longitudinal study of child growth and development in four rural communities in Guatemala (Martorell et al. 1995a). As part of this study, free food supplements were provided on demand to all inhabitants in the four communities. Findings from this study showed that early nutritional intervention can improve significantly the physical growth and development, bone growth and skeletal maturation of mild to moderately malnourished infants and children (Himes et al. 1990, Martorell et al. 1979, Schroeder et al. 1995).
In 1988-89, the former participants of the INCAP longitudinal study, by then adolescents and young adults, were the subjects of a follow-up study. This has provided a unique opportunity to assess the long-term impact of an intervention designed to improve the growth and development of malnourished children.
Specifically, the objective of the analyses presented here was to determine whether there is an effect of early nutritional supplementation on bone mineralization during adolescence. Further, because some evidence indicates that enhancement in bone mineralization may be independent of other more general so