NATURAL: Nutrients obtained from whole food sources
SYNTHETIC: Isolated nutrients that are made artificially
Although our bodies and digestive systems are far different than those of our dogs, this same concept applies. When we eat real, whole foods, we're not just consuming individual nutrients. Instead, we're consuming a large range of vitamins, minerals, fatty acids, enzymes, and other co-factors. This allows all of the nutrients to be used optimally by the body.
Synthetic nutrients (the vitamins and minerals you see in most commercial dog foods and treats) are missing the transporters and co-factors associated with natural nutrients because they have been "isolated" during the manufacturing process. This means that they can not be recognized or used by the body as effectively as the natural version.
Natural nutrients found in whole foods, such as bison liver, contain the optimal, natural combination of vitamins and minerals that work with each other to make sure your dog is absorbing all of these vital nutrients.