Nutrition, Cognition and Economic Outcomes in Tanzania.

Website Link:


Institution Affiliation:  Harvard University


Principal Investigators:  Plamen Nikolov (Harvard), David Cutler (Harvard)


Short Project Description (150 words):

Large estimated market returns to education in developing countries have stimulated policy interest in improving investments in schooling. Though many factors influence individual schooling decisions, an important and unstudied alternative mechanism influences learning and educational attainment — poor in utero environment biologically constrains cognitive development, learning capacity and therefore subsequent demand for schooling.


Using a field experiment, this project examines (1) the causal impact of micronutrient deficiency (specifically for folic acid, B6 and B12) in utero on cognition and children’s schooling, and (2) whether parents allocate resources so as to compensate for or to reinforce inequalities in initial endowments across children. To address these two questions, the research team has collected follow-up data on an individual-level randomized trial of nutritional supplements offered to HIV-pregnant women in Dar es Salaam, Tanzania initially conducted between 2001 and 2004.

Neuroscientists have identified that deficiency in four micronutrients — B6, B9 and B12, and iodine — results in irreversible and continuous damage to individuals’ cognitive capacity. This project focuses on these nutrients because only they exert persistent and continuous effect on learning over the lifespan of individuals. Individual level randomization and a large sample size enable the research team to detect causal effects vis-à-vis previous studies.

The research team uses biomarker data and has collected cognitive tests with children to proxy respectively individuals’ health status and cognitive development. Of particular interest is the possible role of micronutrient deficiency in explaining gender differences in schooling outcomes in Tanzania.