Inescapable hunger? Energy cost accounting and the costs of digestion, pregnancy, and lactation

Abstract

This paper adjusts reconstructions of per capita food consumption in England from the eighteenth to twentieth centuries by factoring in the energy costs of digestion, pregnancy, and lactation. Digestion costs arise because the body has difficulty digesting certain components of food. Incorporating digestion costs reduced the calories available per capita by 12.7 per cent in 1700 but only by 4.9 per cent in 1909 because of changes in diet. The energy costs of pregnancy and lactation were lower only reducing calorie consumption by 2.5 per cent. These adjustments suggest a more pessimistic level of calorie availability before the twentieth century.