When T. S. Ashton wrote his essay ‘The treatment of capitalism by historians’ in Hayek's Capitalism and the Historians, he regarded the ‘hungry thirties’ as a novel and unwelcome epithet for the years before the Second World War. Ashton's fears that the 1930s would become labelled in this way were borne out when Branson and Heinemann chose ‘Eating or not Eating’ as one of their themes and later when the History Workshop Journal took up the question in the 1980s. However, this social concern about the diet of the 1930s has eluded close analysis. The purpose of this chapter is to attempt a quantitative evaluation using contemporary data, even though this raises problems of a conceptual nature. It is difficult today, let alone in the 1930s, to agree upon a standard by which health might be measured; in consequence, the use of the term ‘malnutrition’ is fraught with difficulties, since it may mean over-nutrition as well as under-nutrition, for which it is commonly used. When used in place of under-nutriton, it may mean a diet that failed to provide people with sufficient amounts of various foods to maintain normal levels of physical activity and, in addition, failed to provide normal patterns of development in children and young persons or the maintenance and repair of tissue in adults. This is not necessarily an extreme condition characterized by starvation or sterility or overt signs of ill-health. However, diets restricted in variety, as when the percentage of energy from carbohydrate sources such as starchy foods rises above 60 to 70 per cent of the total energy value, may be defective – even if only marginally so. Any search for malnutrition in interwar Britain has to be done against the background that the food supply appeared to provide adequate resources for the population in aggregate terms.