With just a few words, they summed up cat nutrition really well. As someone who has been feeding pets for 11 years, this statement made me happy:
Ten thousand years ago, humans domesticated cats. We became farmers and started storing grains. Storing grains brought mice and vermin, and we used cats to kill the mice. They ate the mice, not the grain.
But wait! Cut to commercial, and I see nothing but Purina commercials. Dog Chow, Cat Chow, Pro Plan, etc.
A company famous for using grains grains grains in their food.
Nowadays, nutritionists vets and pet owners know cats are obligate carnivores. This means they need meat to live. Meat = nutrition, grain = waste.
Non-meat ingredients do serve a purpose, however. Cranberries are great for raising pH and eliminating UTIs and other bladder-related issues. Some roughage (rice, vegetables, etc) is needed for fiber, but very little. Essentially, since cats are natural predators, any bits of grain or fruits/veggies you'd normally find in a bird's or mouse's gut will do.
But wait! Let's look at the first few ingredients in Purina Cat Chow:
Poultry by-product meal, corn meal, corn gluten meal (so corny it's in there twice!), ground whole wheat, brewers rice, soy flour, animal fat. The list goes on, click the link above to read the rest.
Sounds yummy, doesn't it? Now, when you hear by-products there are many types: The by-products you'd find in hot dogs, and carcass waste. Guess which one is often used for pets, since the other one is used for people?
(Translating their ingredients into people food, Cat Chow is nothing but Tortilla Chips, Bread, Tofu, and bits of 'meat' you yourself would never eat. This is my opinion, but the ingredients speak for themselves.)
My mom used to feed Cat Chow to our pets when I was a child. They all had radioactive-orange poop that would make the litterbox REEK. Now that I know nutrition, I don't let my friends and family do this to their pets.
Long story short, don't let commercials and flashy ads fool you. Odds are, if you see it on TV it's probably not a good brand to feed your pet. Now back to our regularly scheduled programming.