My situation before the long-winded response: Lemon eats canned food currently, until I’m able to wean her onto a cat-specific raw food diet.
My big beef (ha, I went there) with Purina is the amount of by-products and gluten in their formulas. Before I continue, I have to stress that I know nothing of doggie nutrition, so this is coming from a cat-lover’s POV. Gluten should never be one of the top ingredients in a cat’s food, which you’ll find is the case with a lot of Purina’s dry formulas. No amount of vitamin supplements could possibly justify feeding a cat a dry food diet. Without even touching on the whole “not getting enough hydration” thing: Cat’s thrive on a low carb, moderate fat and high protein mixture. It is nearly impossible to find a dry food diet that matches this description. After months of research, I finally gave up trying and went with wet food (which can still be god-awful for them, if it’s from certain brands like Friskies, just as @blueroses said).
Even if you can manage to find a wet cat food that doesn’t have soy or gluten in it, be mindful that many (including Purina, I’m sorry to say) have carrageenan, which is bad juju all around. If you don’t want the scientific analysis, all you need to take from the internet is:
There is evidence from studies performed on rats, guinea pigs, and monkeys that indicates that degraded carrageenan (poligeenan) may cause ulcerations in the gastro-intestinal tract and gastro-intestinal cancer.[18] Poligeenan is produced from carrageenan when subjected to high temperatures and acidity.
For some, this is just hippie silliness, and maybe they’re right. You can get cancer from anything, as the old saying goes. But if you’re on the safe/neurotic side, it feels like you’re feeding your pet a ticking time-bomb. As for the heavy amount of byproducts, that’s more of an ambiguous point that is up to the consumer to decide the final verdict on. While I don’t personally believe it’s okay for my cat, I understand that while our pets are eating diseased animals (which is the definition of “by-product”), their stomachs can in most cases tolerate low doses of salmonella and e. coli (much unlike ours).
While I don’t believe vets get a huge cut from selling these products (if any cut at all), I do believe it’s more and more common to find a vet that has been around products such as Purina throughout their entire medical history, and this can be troublesome if the bigger picture is not considered.
Admittedly, it’s hard to consider the other half of the coin when you’ve endured years of learning otherwise. Imagine if your local veterinarian touted a homemade raw food diet for your pet, with additional vitamin supplements for optimal health. A good portion of their patients would think they were crazy, and complain that all they wanted to do was feed their pet something easy. It makes sense that vet clinics sell the products they do. Most customers want convenience, and that is their choice. I do wish the raw food movement would speak out more frequently as a viable alternative (and not come off as crazy kooks so much), but progress is being made, nonetheless. If anyone’s curious on this, here’s a great place to start.
To bring this ‘round full circle, the short answer is: feeding your pet “people food” can’t be any worse than feeding them dry food (or some wet foods), as long as you stay away from the no-no foods that the brilliant minds of Fluther have already suggested above.
At the end of this response, I’m still just a white-collar worker, with no professional medical background to speak of. What I do have is an insane love for my kitty and too much time on my hands that allows me to research all of this extensively.
This was a GQ, and I’ve enjoyed reading all the responses here!