Potatoes and population growth

“The traditional explanation for the [dramatic] rise in population [in the 18th and 19th centuries] is that medical advances, such as the understanding of the germ theory or the innovation of vaccinations, and improvements in public sanitation greatly decreased infant and child mortality , which in turn led to an increase in population. However, in recent years, scholars such as Thomas McKeown and Robert Fogel have argued that the increase in population was mostly due to an improvement in nutrition rather than the advances in medicine or sanitation. McKeown argued that the decline in mortality began to occur well before the most important innovations such as antibiotics or vaccinations, which did not become prevalent until the 20th century, and therefore, there is scope for other factors to contribute to the rise in population. Fogel argued that since height is positively correlated with nutritional investment during childhood as well as lower mortality rates, then the observation that heights in America and the UK were increasing is evidence that nutrition was improving during this period. ....

[W]e argue that [a] ... main contributor [to nutrition] was ... the potato. Potatoes are extremely nutritious and a very "cheap" source of calories. They produced much higher yields per acre relative to pre-existing Old World staple crops. Historical survey data from England show that if a family of four were to subsist on only one crop, it would require 66% less land if it were to plant potatoes rather than staples such as barley, wheat, or oats. Potatoes are also easy to store and were popular as fodder for livestock through the winter. Therefore, cultivating potatoes also indirectly improved protein intake. ....

Our results suggest that the availability of this high-yielding crop dramatically increased population and urbanisation. The introduction of potatoes can explain 22% of the rise in population and 47% of the rise in urbanisation during the 18th and 19th centuries.”

Nathan Nunn and Nancy Qian, "Potatoes, the fruit of the earth", Vox EU, 5 August 2009.

www.voxeu.org/index.php?q=node/3845

Economists Nathan Nunn and Nancy Qian teach at the University of British Columbia and Brown University, respectively.

Larry Willmore notes:

Adam Smith, a Scot, in 1776 judged potato-eaters from Ireland to be "the strongest men and the most beautiful women perhaps in the British dominions" whereas the Scots, "who are fed with oatmeal, are in general neither so strong nor so handsome". The English, "who are fed with wheaten bread", rank between these two groups.

Thanks to Larry for the Tdj.