Background: The coexistence of micronutrient deficiencies and obesity and their adverse effect on children's development is understudied. Aims: The aims of this dissertation were to: 1) describe the link between economic changes and child nutritional outcomes by linking indicators related to immediate and underlying determinants; 2) assess neurocognitive outcomes of response inhibition and accuracy to adolescents exposed to 'iron deficiency/iron deficiency anemia (ID/IDA) in infancy', 'overweight/obesity (OW/OB) in adolescence', or 'both' compared to those without these conditions; and 3) assess the adverse outcome of youth externalizing behavior problem exposed to 'ID/IDA in infancy', 'OW/OB in adolescence', or 'both' compared to those without these conditions. Methods: Study 1 focuses on the economic growth and nutrition profiles of Brazil, Chile, and Mexico from 1990 to 2010. Estimates for all indicators were retrieved and reconstructed from data sources including the Ministry of Health of each country, the Organization of Economic, and Co-operation and Development and Food Agriculture Organization of the United Nations. Study 2 and 3 uses data from a longitudinal cohort study of Chilean infants who participated in a randomized controlled trial of iron to prevent iron deficiency anemia were used. The Stroop computerized task was used to assess individual's reaction times and accuracy. The Achenbach's Youth Self Report was used to assess clinically meaningful externalizing behavior problem. Results: Study 1, presents evidence indicating that economic growth affects child nutritional outcomes through several pathways. Study 2 found that the combination of poorer brain-circuit development during infancy due to ID/IDA and the inflammation of fat due to adolescent OW/OB may have additive effects on reaction times. Study 3 found that adolescents who experienced a two-hit insult of ID/IDA and OW/OB had a positive deviation from additivity (RERI=1.4; S=2.9; AP=40%) and multiplicativity (OR=1.7; 95% CI: 1.1, 2.7) on youth externalizing behavior problem. Conclusion: The dual burden of nutritional disorders among children are closely linked to their economic growth and nutritional transition. The two-hit insult concept proved useful in understanding the additive and multiplicative effects of two independent nutritional insults and warrants further application.