Given the uncertainty surrounding the safety of genetically modified organisms (GMOs), the precautionary principle and constitution provide that consumers should have the right to access adequate information on the presence of transgenics through food labelling. This article discusses the implications of proposed modifications to GM food labelling in Brazil. Current labelling legislation and the government agencies involved in labelling do not guarantee that food products not bearing GMO labels are free of transgenics. The approval of Chamber of Deputies Bill No. 34/2015 goes against the Consumer Protection Code by undermining consumer autonomy and choice. In addition, it is likely to weaken the country’s biosurveillance capabilities to identify and seize products that have a harmful effect on the health of humans, animals and the environment. The proposed changes constitute a retrograde step in the regulation of food labelling in Brazil and violate the individual and collective rights enshrined in the Federal Constitution, Consumer Protection Code, and international agreements signed by Brazil.