There has been a growing interest in biofuel production to reduce oil dependence in the transportation sector. However, this has also sparked a debate on how the introduction of biofuels may jeopardize food security. In this paper we evaluate the effects of biofuel production on food security using system dynamics. First, we developed a system dynamics model to understand the long-term interaction between food production, biofuel production and livestock farming. Then, we calibrated and applied the model to the Colombian case.