Height and calories in early childhood

- Model the formation of height using a production function approach.
- Estimate the model using a rich panel data set from Guatemala.
- Examine the importance of endogeneity, measurement error, parameter heterogeneity.
- Validate the model by comparing impacts with height gaps from a migration study.
- Predict gains in height from closing the calorie gap between Guatemala and the US.

This paper estimates a height production function using data from a randomized nutrition intervention conducted in rural Guatemala from 1969 to 1977. Using the experimental intervention as an instrument, the IV estimates of the effect of calories on height are an order of magnitude larger than the OLS estimates. Information from a unique measurement error process in the calorie data, counterfactuals results from the estimated model and external evidence from migration studies suggest that IV is not identifying a policy relevant average marginal impact of calories on height. The preferred, attenuation bias corrected OLS estimates from the height production function suggest that, averaging over ages, a 100 calorie increase in average daily calorie intake over the course of a year would increase height by 0.06 cm. Counterfactuals from the model imply that calories gaps in early childhood can explain at most 16% of the height gap between Guatemalan children and the US born children of Guatemalan immigrants.