I read an article about the ingredients in commercial dog food. It is so terrible. It is hard to say, but I will say it, to warn you. It has the the remains of dead animals, many of whom died of diseases, such as cancer. That is why it is so cheap.
If you switch your dog to people food, it will take a time of acclimation in which your dog may have loose bowel movements. It may take up to a week. Many vets will discourage you from doing this. It is a controversial topic, as are ALL topics in natural health. However, in my experience, you will notice that your animal becomes much healthier. You should notice the changes in the animals coat and general behavior. This will help you to know that you made a good decision.
I am going a step further and switching my Yorkie to raw foods, after consulting with the owner of the raw foods store, near me. He assured me that dogs do wonderfully on raw food, just as people do. His dog thrived beautifully on a total raw food diet.
I add raw meat to my dog’s diet, though, as that seems to be a good idea. It does not seem like dogs were meant to be total vegetarians. I know that informed people will disagree on this. As with all things, do your own research and do what seems right to you.