Reject #3 - Any Grains

Next, I reject any product containing grains, especially genetically modified grains, (wheat, oats, barley, quinoa, rice, flax (linseed), corn (corn starch, corn gluten meal). Less costly than meat, grains are often used to boost the crude protein numbers in place of adding more meat to the product.

See Ms. Thixton's article 'What you should know about Grains in your pet's food.'

To repeat, cats are obligate carnivores and get their protein from animal sources, not plants. Grains, fruits and starchy vegetables are ‘fillers’, none of which have any nutritional value for cats, and all of which have questionable effects on a cat's digestive system.

And how about by-products?  - Reject them. Obviously cats in the wild eat nearly anything and everything from their prey. (Cats in the wild do reject various parts of their prey and leave the parts strewn about the kill site.) Examples are below. No... I reject by-products because it's a category ripe for manipulation by unscrupulous manufacturers. 

According to AAFCO, meat by-products are "non-rendered, clean parts, other than meat, derived from slaughtered mammals. Includes, but not limited to lungs, spleen, kidneys, brains, livers, blood, bone, partially defatted low temperature fatty tissue, and stomachs and intestines freed of their contents. It does not include hair, horns, teeth, and hoofs."

( I wonder… how do pet food manufacturers separate the fecal matter contaminants from the ‘by-products?’ How much chicken or cow poop is in ‘by-products'?) 

Here’s an article title that makes me laugh out loud (who are they trying to con), again by Susan Thixton, TruthAboutPetFood.com -  "Purina Says By-Products are “Nutrient Rich.”

I put the can back on the store shelf if the description contains the words 'meal' or 'bone meal', like in Chicken Meal. 'Meal' is the rendered product from animal tissues, excluding the things noted above under 'By-Products.'  Rendering is a process wherein meat is first over-cooked to remove the water. It is then baked until it becomes a residue. It becomes a highly concentrated powder - or meat meal. Low quality meat meals can come from slaughterhouse waste, spoiled meat, and/or dead/dying or diseased animals.

"This is one of those rendered products that could contain anything from euthanized pets to zoo animals to roadkill to expired meat and the styrofoam wrapper it comes in." - Emily Parker - Catological.com.

"There is a very suspicious reason as to why the pet food ingredient 'chicken' is not required to be sourced from a slaughtered animal. That reason is the common practice of culling baby male chickens and spent layer hens by a macerator. The birds are ground alive (they are not slaughtered). As explained to me, the end product is sold to pet food as 'chicken' and/or 'chicken meal'." - Susan Thixton, TruthAboutPetFood.com - Inexcusable Pet Food Ingredient Definitions

Throw out artificial colorants and flavorings too. Coloring is added to cat food to make it more appealing to the human eye. It is a potential allergen and completely unnecessary for a cat.

Why would a cat food manufacturer be so obsessed with food color? Adding color is a 100% marketing gimmick. It's a subtle example of hype. Here's a list of the color additives just one company uses to influence your visual, aesthetic sensibility: Titanium Dioxide, Beta Carotene, Sodium Nitrite, Canthazantin, Caramel Color, Iron Oxide, Red 3. Read about these color additives below.

‘Natural flavor’ (as contrasted with unnatural flavor?)  I'm very suspicious of something called 'natural flavor.' That term could mean anything at all. Old car tires could be used to flavor something. Ground up roofing shingles could be used to flavor something else. The term is just too broad to not be a catch-all, blanket phrase for anything manufacturers want to put into the food. Worst of all, 'natural flavor' usually occurs high up on the ingredients list. I simply do not trust the term - or the ingredient -at all.

• caramel* (produced from caramelized sugar, caramel is a brown colorant in pet food that is designed to 'produce appeal' by making the color 'richer.' One might ask - "Who's appeal?" "My cats?" I suspect that my cat doesn't give a hoot about his food's color. lol 
• sodium nitrite (promotes color retention and can be carcinogenic)
• red 3 (artificial colorant)
• beta carotene (color enhancer)
• canthaxanthin (color enhancer)
• carmine (red colorant)
• annatto extract (color enhancer)
• iron oxide (unnecessary coloring additive which is derived from rust! - 100% marketing gimmick, and usually the sign of a cheap cat food.))
• titanium dioxide (potentially carcinogenic artificial colorant which may cause DNA damage, inflammation, cancer, and genetic disorders. Used to provide whitening to offset the natural, normal gray appearance in canned poultry and fish cat food to make the product more visually appealing to the consumer (and I don't mean the cats). It is indigestible.)
• sometimes the label just says "added color"
• sodium acid pyrophosphates (SAPP) (used as a palatability additive, a flavor enhancer)

* for more about caramel read this article, again by Susan Thixton, TruthAboutPetFood.com: Coke, Pepsi and Pet Food

I also reject any product where the metal can contains BPA - a commonly used chemical in the plastic lining of canned foods. BPA is an “endocrine disruptor chemical”, and as such may interfere with the body’s endocrine system and produce adverts developmental, reproductive, neurological, and immune effects.” - from the National Institute of Environmental Health Sciences.