The first decades of the 20 th century were marked by a crisis. The impact of the Great War, the rise of the workers’ revolutionary movement and the National Socialist expansion as well as the disaster of the 1929 crash and the great depression of the 1930s created a landscape of tension, radicalism and political instability. In this context, nutrition emerges as an excellent ground from which to explore the genesis of experimental knowledge, the social interests involved, and the transfer of knowledge and practices to public health, the economy, trade and politics. The exceptional confluence of all factors influencing the interwar period contributed to building the problem of nutrition. This book offers a wide perspective including international agencies committed to a global approach to define nutritional problems, agricultural reforms, surveys in different countries and rural areas, methodological agreements on nutritional standards, the main trends of experimental research, the dreadful impact of the war and some experiments developed in internment camps. The author examines nutrition as a cornerstone to show interactions between science, politics, economy and public health.