The US Food and Drug Administration recommends that any freezer used to store food be set at 0 degrees Fahrenheit. The FDA recommendation is based on food safety guidelines that were developed to educate consumers and keep them safe from food-borne bacteria or pathogens.
Per the FDA, frozen food will last indefinitely when stored at 0 degrees. Storing food at that temperature will not kill bacteria but will prevent bacteria from growing, keeping the food edible. The FDA recommends purchasing and installing a low-cost freezer thermometer to monitor the temperature inside of the freezer to ensure that it remains at 0 degrees.