Natural everything has become quite a trend lately. As with most trends, it’s not a bad thing at all; I’d even venture to say it’s a good thing. Unfortunately, anything trendy gives some of the less ethical corporations an opening to take advantage of people. The Association of Animal Feed Control Officials (AAFCO) is the group in charge of writing definitions for ingredients in animal food. They are not a regulating agency, but most states have adopted their guidelines.  AAFCO’s definition for “natural” is actually pretty permissive. It includes anything that was derived from a natural product and allows for some chemically synthetic additives “in amounts as might occur in good manufacturing practices.”  In other words, natural can still be highly processed.
Also, if the package says “natural with added vitamins and minerals”, this actually means that the product would fit the definition of natural until they added the possibly artificial vitamins and minerals. 
The term “human grade” isn’t regulated in the pet food industry at all. Neither AAFCO nor the FDA has a definition for “human grade” pet food.  Even if they did, fit for a human does not equal fit for a pet. Our bodies are designed differently and do not have the same nutritional needs. For instance, dogs and humans can generally make sufficient amounts of taurine from plant based sources. Cats, however, cannot manufacture their own taurine and need to eat animal proteins to get what they need.  Every species of animal has unique nutritional needs, so be sure to find foods that are designed for your pet.
No Animal Byproducts
Another common label on pet foods is “no animal byproducts.” There are a lot of rumors flying around about byproducts. The claims that animal byproducts might be euthanized dogs and cats are simply untrue. By AAFCO definition, any meat byproduct that is not specifically listed by the species it came from must be from cattle, swine, sheep or goats. 
Also, animal byproducts are frequently nutrient dense. Simply put, byproducts are anything left over after the original product was processed.  This is usually the parts that us picky Americans don’t want to eat. For example, organ meats are extremely nutritious but not nearly so appetizing, and certain parts (i.e. lungs) that are not considered edible for humans would be part of a dog’s natural diet. These are common meat byproducts. Some things byproducts cannot be are “hair, horns, teeth and hoofs.” 
One last trend I need to discuss is the “grain-free” diet. The first problem is that grains are not the most common pet allergy. The usual allergy triggers in animals are proteins. Beef, chicken, fish, and dairy are among the top.  Of course, grains do have protein too, and wheat is included with these as a common dog food allergen.  However, grains can’t all be lumped together as one thing. Most grains do not make it into the top 10 list of pet food allergies. Why leave out barley, rice, rye, oats, etc? With all the benefits of eating whole grains, I’d hesitate to throw it all out the window.
So, as you can see, a lot of advertising money goes into making you believe the food you’re buying is the best. I’m not trying to discourage you or make you feel like you can’t trust anyone. I just want to make you aware. In short, don’t judge a food by its package.
If you want to learn more about what you SHOULD be looking for in your pet’s food, keep watching for Part 2 of How to Pick a Pet Food.