Biochemists investigating the problem of the vitamins in the early years of the twentieth century were working without an object, as such. Although they had developed a fairly elaborate idea of the character of the ‘vitamine’ and its role in metabolism, vitamins were not yet biochemical objects, but rather ‘functional ascriptions’ and ‘explanatory devices’. I suggest that an early instance of the changing status of the object of the ‘vitamins’ can be found in their stabilization, through the course of World (...) War I, as bio-political objects for the British and Allied war effort. Vitamins emerged as players, active agents, in Britain’s wartime bio-political problems of food distribution and population health and because of this they became increasingly real as bio-political objects, even prior to their isolation as bio-chemical molecules. I suggest that the materiality of our biology has agency in the development of political regimes and schemes. (shrink)