My cat is healthy and fine on dry food
Lisa Pierson DVM makes a very good point on her website catinfo.org. She decries dry cat food for several reasons, the most important of which is that it “does not come close to resembling a bird or a mouse”. It is contaminated with all kinds of nasties: bacteria, fungal mycotoxins, storage mites and their feces etc.. It is stored for long periods unrefrigerated yet is coated with fats. It can be dangerous but looks benign.

My cat is fine eating dry cat food
We know that if we were buying food for ourselves we would not contemplate buying it. We don’t live off crappy biscuits so why should our cat companions?
The point she makes is that cat owners who decide to feed their cat exclusively dry cat food proclaim that their cat is doing fine on it. They say their cat has no outward signs of illness so what is all the fuss about?
The supporters of dry cat food continue to use it until their cat falls ill and they find out that the underlying reason is quite possibly dry cat food. One problem is that some vets won’t tell them that because they sell dry cat food at a commission.
Lisa Pierson writes that cats with cystitis were fine on dry cat food until they developed cystitis (feral cats have a much lower incidence of cystitis than domestic cats). Cats who develop urinary tract diseases such as a blocked urinary tract are fine until the cat struggles to pee or at worst dies due to a ruptured bladder. Cats who spent their lives feeding on dry cat food are fine until their owners see the signs of Type II feline diabetes.
Cats look fine even when they are constantly mildly dehydrated and hypoglycemic because many cat owners can’t see the signs of the development of a full-blown illness. Outwardly they are difficult to spot but the high carbohydrate levels and lack of moisture in dry food can cause “havoc” with a cat’s blood sugar levels and urinary tract health.
Cats have evolved to drink water in their food (mice are 70% water) rather than drink water from a bowl. They don’t have the hard-wired drive to drink more water if their dry food diet is dramatically low on moisture content.
So the point she makes is that it is not good enough to say a cat is fine on dry cat food. She believes in preventative nutrition as all concerned cat caretakers should.
Good nutrition promotes good health. There is a ton of information for humans, by humans on good nutrition and how it can benefit long term health. Why isn’t there the equivalent for our cats?
The reason is clear: in general the cat is undervalued. That is not to say all people undervalue the cat but enough people do including the pet food manufacturers.