What is the difference between a supplement and a “complete and balanced” pet food?

A product represented as complete and balanced is intended to provide total daily nutrition for a stated life stage and must be supported through an accepted nutritional-adequacy pathway in the relevant market. Treats, snacks and supplements are generally not designed to be the sole diet. Buyers should avoid copying complete-diet language onto a complementary product and should make feeding directions clear. The distinction affects formulation, substantiation, label language and how customers understand the product.