American Pie: The Imperialism of the Calorie
Nick Cullather explains how the scientific discovery of the calorie meant food values could be quantified – and the US could make food an instrument of foreign policy.
In Super Size Me, his 2004 documentary on the fast-food industry, Morgan Spurlock asks Americans if they know what a calorie is. A few shake their heads, but most gamely guess that it has something to do with fat. ‘It’s on the side of the cereal box’, one explains. ‘Calories are not good’, another knows for sure. Even a specialist had difficulty recalling that a calorie is a measure of the energy content of food, an amount sufficient to raise the temperature of one litre of water one degree.
In the first half of the twentieth century, figures of all kinds, from gross national products to birth rates, became the language of statecraft, yet the original meaning of the numbers melted away, leaving behind distinctive patterns on thought and policy. The calorie is one such measure. Its initial purpose was to inventory the food supplies and appetites of whole populations, but it grew instead into a measure of inspanidual self-control. Along the way it altered the logic of international affairs, placing food at the centre of trade controversies, humanitarian crises, and development schemes.