Abstract

There is a complex inter-relationship between nutrition and morbidity in human health. Many diseases reduce nutritional status, but on the other hand, having low nutritional status is also known to make individuals more susceptible to certain diseases and to experience more serious illness. Modern evidence on these relationships, determined after the introduction of antibiotics and vaccines, may not be applicable to historical settings before these medical technologies were available. Thus, this paper uses historical data from the London Foundling Hospital to determine the causal effect of nutritional status of children proxied by weight and height-for-age Z-scores on the odds of contracting five infectious diseases (measles, mumps, rubella, chicken pox and whooping cough) and on sickness duration from these diseases. I identify a causal effect by exploiting the randomisation of environmental conditions as foundling children were removed from their original home, then fostered with families in counties nearby London and later returned to the Foundling Hospital’s main site in London. I find no effect of nutritional status on the odds of contracting the five diseases, but I do find a historically important and statistically significant effect of nutritional status on sickness duration for measles and mumps but not for the other diseases. These findings confirm the importance of underlying nutritional status for measles morbidity, provide new evidence of an effect for mumps, but challenge earlier assertions that whooping cough morbidity was related to nutritional status. These results suggest that improving nutritional status in the late nineteenth and twentieth centuries would have reduced the severity (and perhaps case fatality rate) of measles and mumps infections, whereas the decline in pertussis mortality before vaccination was likely caused by other factors.