The facts are that dog food and food for human consumption go by two different standards. For example, if you see on the dog food package that it is chemical free, the simply means that there were no chemicals added to the product after it reached the factory for processing. Before the product got there it could be pumped full of all kinds of chemicals, steroids, and even meat from other dogs and cats. They do not need to disclose this on the dog food packages.
Another thing that most people don't know is that, when fed properly a dog will live twice as long as the average life span of our pets. This is because the food that we are feeding them, the quality food from the pet store, is actually killing our dogs. It's a sad situation, but one that can be corrected if you take positive action and really dig for the facts.