In 1877 the German physiologist and nutritionist Carl von Voit published diet parameters which included minimum intakes of carbohydrates, proteins and fats. As a minimum daily intake of protein Voit arrived at a figure of 118 g. This figure was questioned mainly by supporters of the so-called food reform, because the required protein intake would hardly be feasible without substantial meat consumption. To disprove this claim and to show that the vegetarian way of life was justified, reformers such as Mikkel Hindhede and Carl Röse conducted experiments demonstrating that the long-term adherence to diets with a daily protein intake of less than 30 g was possible without causing a negative protein balance. It was, however, only after the famines of the First World War that the concepts of the diet reformers met with greater interest. As they promised a better, from imports independent supply of food, the national socialist regime after 1933 made it the centre of a new food policy that aimed at autarky. Thus, the history of the "protein minimum" provides insights into effects and limits of nutrition research under the restrictions of economic requirements, moral considerations and prevailing traditions.