Feeding Your Cat

Why are our cats fat?  More and more, science is pointing to what we are feeding cats as the culprit causing obesity rather then how we are feeding cats.  Cats are obligate carnivores.  Simply put that means they must eat meat or they die or they get sick, or at best they do not thrive.   They have evolved metabolically to utilize meat protein and for all their needs, therefore they do not utilize carbohydrates well; in fact, they do not need to consume them as they can produce glucose directly from protein.  Cats either lack enzymes used in digesting and metabolizing carbohydrates, or are poor producers of them.   Millions of years ago in a quirk of reverse evolution ancestral cats turned off the genes that manufacture some of those enzymes, and until they domesticated themselves and moved into our homes, this genetic streamlining had not been a problem.  Cats fed high protein, low carbohydrate diets tend to lose fatty weight if they are obese, maintain good muscular weight if they are not, and are less likely to experience other problems associated with eating high fiber, high carbohydrate diets.   It is the carbohydrates in dry foods that make cats fat because the cat is unable to readily utilize the carbohydrate, but preferentially stores them as fat.  To make matters worse, we “free feed” kibble allowing cats to munch whenever, whether out of boredom or protein hunger.  Dry food is over-eaten junk food (“Cracker Jacks”) for many cats.


If your cat licks the air or a part of his body when you scratch his back, this is a sign that he has become too fat to clean himself in that area.


 Forget the television commercial that talks about “the grains and greens your cat craves.”  Any preference for food can be a learned response…but an instinctive craving for meat exists in kittens as young as three weeks.  As young as three weeks, a kitten will growl and hiss when presented with raw meat.  Cereals have yet to produce that response!  As for the claim for greens, the only vegetable matter the feline can utilize are those predigested in the gut of a prey animal or those grasses it eats to help it regurgitate a fur ball!  Since the majority of us are unable or disinclined to provide a balanced raw meat diet for our resident carnivore, we need to find the next best substitute.

 Cats need to eat a high quality canned diet rather then dry formulations.  Why not convenient, less expensive kibble?  Because the only way to make dry food is to add grain to meat protein…. lots of grain in fact.  Kibble is approximately 35% carbohydrate.  We compound the problem by free feeding, allowing the cat to nibble out of boredom or from protein hunger.

 Another big benefit in feeding canned food is water.  As descendants of felis lybica, a North African desert cat, the house cat retains those adaptations for living in a dry climate…they do not feel thirst until they are already physiologically dehydrated; this in an animal who already concentrates its urine, depending primarily on food as a water source.  Male cats walking around in a state of dehydration who crunch down on kibble as their daily fare will concentrate urine even more, which may cause crystals to form in the urine and cause cystitis (inflammation of the bladder wall), thus potentiating urethral blocking.

Cats’ kidneys are already concentrating urine as they eliminate toxins from the bloodstream.   Dehydration overworks the kidneys and can only shorten the life of these precious organs.  Renal failure is a leading cause of death in older cats.  Consider the damage a lifetime of kibble may do to a cat’s kidneys.


Fat Cats:

fat bob

Who... me?


Nationally cats, like their human counterparts, are experiencing an obesity epidemic.  Besides all the health risks they share with humans from being overweight, they are also at risk from a feline disorder called hepatic lipidosis or fatty liver disease.  Cats are not efficient at mobilizing body fat and converting it to energy, so when obese cats stop eating for any reason, fat called out of their tissues and into their livers for metabolism, sits there awaiting manufacture of the enzyme to convert it to glucose.  The process is too slow and most of it ends up replacing liver cells.  Unchecked, this disease destroys the liver.

 In fact, the cat’s metabolism will preferentially cannibalize its own muscle mass for glucose conversion before it will convert its body fat.   Thus we see cats that are both obese AND poorly muscled.  They have cannibalized their muscle, but their fatty tissue is still intact.  Many such cat also have very flaky skin. Anorexic cats may be actually jaundiced, or yellow, from hepatic lipidosis.

 Additionally fat cats are much more prone to diseases such as diabetes, heart stress and cystitis.

Variety In Food Is Important:

 Kittens learn what ‘food’ is by what mother teaches them to eat.  Experiments have been done with kittens where they were taught that mashed bananas were proper food and they happily accepted them as their fare.  To avoid problems throughout life, teach a kitten to enjoy a wide variety of foods…fish, poultry, beef, pork, liver, etc.   (Avoid bananas.)  Creatures of habit, it is very difficult to retrain a cat to a different diet as an adult, so continue variety throughout life.