What caused ingredients to be listed on food labels?

There are legal requirements to provide the ingredients on food labels.

In 1990, the Nutrition Labeling and Education Actrequires all packaged foods to bear nutrition labeling and all health claims for foods to be consistent with terms defined by the Secretary of Health and Human Services. The food ingredient panel, serving sizes, and terms such as "low fat" and "light" were standardized.

In 1992, the Nutrition Labeling and Education Act of 1990 was amended to require the Nutrition facts, basic per-serving nutritional information, are required on foods. Food labels were recreated by the FDA and the Food Safety and Inspection Service of the Department of Agriculture to list the most important nutrients in an easy-to-follow format.

In 2003, the Nutrition Labeling and Education Act of 1990 was amended again to provide basic per-serving nutritional information for foods.

In 2004, the Food Allergy Labeling and Consumer Protection Act was passed. It requires the labeling of any food that contains a protein derived from a group of foods that account for the majority of food Allergies, these include: peanuts, soybeans, cow's milk, eggs, fish, crustacean shellfish, tree nuts, and wheat.