Before I begin, I want to affirm that the title of this research report will also be the title of my dissertation. During the aftermath of the Great Depression, images of poverty and disease characterized descriptions of life in Puerto Rico. The island was particularly infamous for its malnutrition situation, especially among children. Public health experts associated this problem with the deficiencies of the island's traditional diet, ignorance of "basic" nutrition principles, and the difficult economic situation. The Rockefeller Foundation (RF) had an important role in the creation of knowledge about the public health and nutrition situation in Puerto Rico by sponsoring various research programs at the Puerto Rico School of Tropical Medicine (STM). The RF also played an important part in the implementations of public health interventions and its representatives on the island contributed to debates about the nature and magnitude of Puerto Rico's malnutrition problem.