My research examines the relationship between commercial nutritional products and the production of nutritional knowledge. Nutritional products, I argue, were central to the emergence of nutrition science in the nineteenth and early twentieth centuries, and shaped many of its central questions, methods and theories. Through an analysis of physical objects, company records, medical and scientific literature, promotional material, as well as popular literature, I recover the changing cultural contexts of production and consumption, as well as the nutritional scientific discussions, within which products were embedded. Products aligned food and science with the economic rationales of the empire, the state, and the market. This alignment shaped the very technical and scientific concepts of nutrition science; it fundamentally transformed how food and the eating body could be known. Our relationship to food and the eating body was not only deeply influenced by the advent of nutritional products, but was reshaped in the image of ‘product.’