Genetically modified organisms, or GMO, labeling alerts consumers to the presence of genetically modified microorganisms or plants that are part of the food products that they buy. Even if the GMOs are not present, but were used in production, this must be indicated on the label. Certain products are exempt from GMO labeling, such as certain processing aids and additives.
As of 2014, the United States and Canada are two of the countries that do not require food producers label genetically modified food, and the U.S. Food and Drug Administration does not require any distinction between GMO and non-GMO foods. Despite this, there is an agency within the U.S. Department of Agriculture, the Animal and Plant Health Inspection Service, that does regulate GMOs.