Grocery and pet store shelves abound with a dizzying array of cat food.   For decades, dry kibble has been the preferred choice for most cat owners.  After all, the bags say it's "complete and balanced," it's easy to feed, and most cats seem to like it.  Unfortunately, dry pet foods, even the high-priced premium and veterinary brands, are the equivalent of junk food for pets.  Feeding dry food to cats is no different than feeding sugared cereals to kids.

Cats are obligate carnivores.  This means they need meat to survive.  They cannot get enough nutritional support from plant-based proteins such as grains and vegetables, because, unlike humans and dogs, they lack the specific enzyme that processes plant-based proteins metabolically.   They need little or no carbohydrates in their diet.  Feeding foods high in carbohydrates leads to any number of degenerative diseases, including diabetes, kidney disease, and inflammatory bowel disease.

Many pet owners feed dry food because it can be left out during the day without spoiling while the cat is left at home alone.  This method of free choice feeding is one of the leading contributors to obesity in cats.  Cats, by nature, are hunters, and it does not make sense that they should need access to food 24 hours a day.  Meal feeding twice a day mimicks their natural hunting behavior much closer, and by feeding controlled portion sizes twice  a day rather than leaving food out all day long, calorie intake, and weight, can be controlled without the cat going hungry.

Dry food is the leading cause behind most urinary tract problems in cats.  While cats who eat only dry food will generally drink more water, they still don't get enough moisture to support all their bodily functions and essentially live in a constant state of low level dehydration, which can lead to bladder and kindey problems.

Due to the high carbohydrate content, dry food dumps unnaturally high levels of sugar into the cat's bloodstream, which can lead to an imbalance of its natural metabolic process.  In extreme cases, this can, and often does, lead to diabetes.

Dry food does not clean pet's teeth.  Most cats don't chew their kibble long enough for any of the scraping action that is the theory behind this myth to kick in.  What little they do chew shatters into small pieces.  Some pet food manufacturers offer a "dental diet" that is made up of larger than normal sized kibble to encourage chewing, but in my years at veterinary practices, I've seen many cats swallow even those larger size pieces whole.  Additionally, dry food leaves a carbohydrate residue in the cat's mouth that actually encourages growth of tartar and plaque.

The one best thing you can do for your cat is eliminate all dry food from his diet and feed a meat based, grain-free canned or raw diet which is consistent with the needs of a carnivore.

You may find that some cats are very difficult to switch from their dry food, further supporting the junk food analogy.  They're literally addicted to the carbs and additives used in these diets - not much different from a sugar or carb addiction in humans.  During the manufacturing process, substances called "digests" (fermented by-products of meat processing with no nutritional value) are sprayed on the outside of the kibble to make it more palatable to the cat.  Most cats wouldn't touch dry food if it wasn't for these flavor enhancers.  For these hard-core addicts, you will need to transition them to a healthier diet somewhat slowly.  Never let a cat go without food for more than 24 hours.