1) Ingredients are listed by weight. If corn is listed 1st or 2nd, you are essentially buying a big bag of corn.   

2) Stay away from by-products, corn, & gluten.  

3) A specific meat (chicken, beef, pork, etc.) should be listed as the first ingredient.  

ANIMAL BY-PRODUCTS are what's left of a slaughtered animal after the parts intended for human consumption have been removed. This meat processing scrap (known as offal) is considered inedible and includes waste material like beaks, feet. backs, etc. These ingredients are nothing more than inedible waste of inferior nutritional value. Furthermore, if the ingredient doesn't identify the source of the meat (chicken, beef, pork, etc.) and just says "meat" it could legally contain road kill, dead zoo animals, dead, dying, and diseased animals, and even euthanized pets from animal shelters.  

The FDA – the highest regulatory authority of pet food – openly allows diseased animals and animals that have died other than by slaughter to be processed into pet food (with no disclosure to the consumer). The FDA also approved poop, dust, plastic, breakfast cereal, candy, hair, & feathers in "feed" grade foods. The exception would be any Human Grade pet food. None of these ingredients would be allowed in a human-grade manufacturing facility.  

CORN not only has a very high glycemic index, it is not easily digestible, and offers no protein benefits. If the ingredient is not listed as whole corn, it is usually just the cob with no kernels included anyway.  

WHEAT GLUTEN is what's left over from certain grains after processing. Glutens raise the protein level on a food label but is nutritionally inferior to meat.  

MEAL is meat product with moisture removed. Not necessarily good or bad but it's definitely been processed.  

So why do some pet food companies include these ingredients in their foods? Because it's cheap and the FDA and AAFCO let them do it. So, what do you do? We recommend foods that are made in human grade facilities from brands that source their own ingredients (and don't let a co-packer find the cheapest ingredient available). Read the label as best you can by avoiding corn, gluten, and by-product which are red flags for an inferior product.  

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