Introduction: the development and legacy of the INCAP Oriente Studies 1969-2009.

A symposium was organized at the request of the History of Nutrition Research Interest Section of the ASN to update the findings on the long-term effects of the nutrition intervention of the Institute of Nutrition of Central America and Panama (INCAP) Oriente Longitudinal Study (1969–77) since the previous syntheses (1–3). The symposium was also cosponsored by the International Nutrition Council of ASN. The original study was a community-randomized, food supplementation trial that contributed important and novel information about the effects of improved nutrition on maternal and newborn nutrition and on child growth and development. Several studies, both cross-sectional and longitudinal, have been undertaken to collect a variety of information on former participants of the study and their families. This unique collection of studies allows the tracing of long-term effects of the nutrition intervention in early childhood on human health and function decades later. The original 1969–77 study was a product of the vigorous and novel research program in human growth and development of the INCAP in the 1960s. In the first article, Nevin S. Scrimshaw, founding director of INCAP in 1949, gives an account of the establishment of this remarkable institution and of its mission, guiding principles, and scientific culture in its early years (4). Dr. Scrimshaw also provided the intellectual (5) and motivational leadership for what became the Oriente study. In addition, Dr. Scrimshaw reviews several studies that preceded and informed the design and methods of the Oriente study. He has remained, through all these years, a stalwart supporter and promoter of the Oriente study. Manuel Ramirez-Zea, Paul Melgar, and Juan Rivera summarize the design and methods of the 1969–77 study and the many studies that have followed, including one just completed that focused on 3 generations (parents in the 1969–77 study, former participants who were children in 1969–77, and their children) and that no doubt will yield important results when the analyses are completed (6). Two articles follow that review the evidence from past and continuing analyses of the original data for the more immediate effects on the nutrition of the pregnant mother, her newborn baby, and her young child. Kathleen Rasmussen and J-P. Habicht (7) summarize the findings about the maternal characteristics that predicted improvements in maternal status and birthweight as a result of the nutrition intervention. A well-known finding from the original study is that the dietary factor limiting birthweight was energy and not protein. The authors also summarize the evidence for differential partitioning of benefits to mother and newborn depending on the mother's nutritional status. Jean-Pierre Habicht and Reynaldo Martorell (8) follow with an article about the evidence and external validity that establishes that the effect of the intervention on child growth was causal, that it was due to improved nutrition from supplementation, and that it benefited some children more than others. This sets the stage for the next article by Reynaldo Martorell, Paul Melgar, John A. Maluccio, Aryeh D. Stein, and Juan A. Rivera (9) that presents evidence of the long-term impact of this nutrition intervention during early childhood on human capital and economic productivity, relying on findings from the 1988–89 and 2002–04 follow-up studies. Perhaps the most noteworthy recent result is a 46% increase in wages in men traced to exposure before 2 y of age to the nutritious drink, Atole, compared with exposure to the less nutritious drink, Fresco. Marie Ruel (10) closes the symposium with an analysis of the implications of the findings from the Oriente study and its subsequent studies for policies and programs worldwide. Perhaps the most profound implication of the Oriente collection of studies has been the identification of the intrauterine period and the first 2 y of life as critical windows of human development when nutrition improvements will have profound and long-lasting benefits on health and well-being. As part of the display at INCAP's booth accompanying the symposium at EB2009, Paul Melgar of INCAP created a historical flyer about INCAP (Supplemental Tables 1 and 2) and developed a list of scientists who were involved with the Oriente study from its inception until today (Supplemental Table 3). We also compiled a list of the many publications in journals and books, as well as theses, that used the data from the Oriente study (Supplemental Table 4).