Dogs can survive for a time on inadequate food, just like us. What may be bad for dogs is certainly a matter of degree. Our dogs get into things sometimes that is said to be bad for them and they suffer no ill effects. That says nothing about a long term diet of chocolate chip cookies though. Because there is so much information out there, much of it just plain wrong, common sense, personal research, and being aware of who is providing the information and why is your best approach to sorting through all the hubbub.
We have to look at what can be shown to be true and go from there. For example, we know that a dog has a different digestive system than we do or sheep do and that means they can digest what that system was designed for. We can feed other things and the body may be able to extract some nutrient from it but the system is then stressed and will fail long before its time. We know that a dog has a relatively short digestive tract and so can best benefit from food that is more easily and quickly broken down. Raw vegetable matter is not quickly or easily broken down.
Here is another opportunity to use our common sense. When we examine what comes out our dogs and find clumps of grass it is apparent they were not meant to digest it. I never find clumps of grass coming out of our sheep or geese and they consume much more of it than do the dogs. If we are not scrutinizing what comes out of our dogs as much as what goes into them then we will not have enough information to make rational decisions about what to feed our dogs or what to believe about what other people tell us we should be feeding them. An analysis of what our dog leaves behind will upset the claims of many dog food manufactures. If you have not yet proven to yourself that a commercial dry grained based food will produce much larger quantities of waste than a meat diet and what that means, then that is where you need to begin your research. One of the first things you will notice when feeding raw meat is the change in appearance and quantity of your dog’s waste.
When we examine our dog’s mouth it is plain that it is not the same design that we have or other animals that chew their food. Dogs do not chew they crush and tear so they need food that can be digested without first grinding it with flat teeth. It is not merely a coincident that canine predators eat animals that do have teeth that grind their food; this is how they receive the nutrients of those things that their prey has eaten. While it is true that domesticated canines (dogs) have adapted over the centuries to live with us they are still canines, they remain physically the same animal with the same biology.