Growth, IQ, Diseases, and the Great Demographic Transition

Using a large sample of cross-country data and very long historical data, this project investigates whether the large burden of parasitic and infectious diseases, protein-energy malnutrition, and iron and iodine deficiency (PID-MIID) among children accounts for the low cognitive ability found in developing countries today and in the West, before and during industrialisation. The marked variations in PID-MIID over time and across countries are hypothesised to be the major force behind the large income differences across nations and income growth in the West since industrialisation, through the channel of cognitive ability. Furthermore, it is proposed that PID-MIID may have been the key driver behind the Great Demographic Transition.