What Should I Feed My Cat?

by Amanda L. Maus DVM
Catalina Pet Hospital
Tucson, AZ

A common question asked by cat parents is what food should they be feeding their cat.  There is no one brand or type that is perfect or the best for all cats.  Certain cats may have trouble with hairballs or have a sensitive stomach and therefore only do well on specific types of food.  Some cats may have medical conditions such as kidney disease or urinary tract diseases that require prescription foods be fed.  The aim of this blog is to help with making decisions on which food to buy for a normal, healthy adult cat, when confronted with all of the different types of available cat food at the pet store.

Mister

Cats are carnivores which means that they require high levels of protein in their diet, usually obtained through eating animal tissue or muscle.  Omnivores, such as humans and dogs, eat a mixture of animal and non-animal foods.  The Association of American Feed Control Officials (AAFCO) recommends a minimum of 26% protein on a "dry matter" (DM) basis for adult cats, as opposed to only 18% for adult dogs.  What advantage do we gain in feeding high protein to our cat?  By feeding high protein, we are providing a proper carnivore diet. Most dry foods are high in carbohydrates which leads to weight gain and obesity. Obesity leads to higher risks of diabetes, hygiene and grooming problems, and joint disease.

Most pet foods only show the % protein in an "as fed" basis on the food label.  Usually this is okay if we are comparing dry foods to one another but it makes it difficult to compare a dry food to a type of canned food.  To show how to covert from "as fed" to "dry matter", let's say the dry food label says 10% moisture, which means there is 90% dry matter (100 minus 10).  If the label says there is 20% protein, we divide the 20 by 90 which equals 22% protein DM.  If the canned food label says 80% moisture, meaning 20% DM (100 minus 80), then 10% protein as fed equals 50% protein DM (10 divided by 20).  Although the dry food label said 20% protein and canned food listed 10% protein, there is actually 28% more protein in the canned food for this example.

Sebastian

Now that we know how to interpret pet food labels, let's look at the pros and cons of feeding dry food vs canned food.  There is a maximum amount of protein that can be found in dry food due to the difficulty of keeping it fresh and stable when stored at room temperature in a bag.  As seen in the example above, canned will typically contain much more protein than an equivalent dry food. There are only a few cat dry foods that contain high levels of protein such as those that are found in canned food. Canned food also has a high amount of moisture which helps ensure hydration and urinary tract health.  Although people worry about wet food leading to bad teeth, most dry foods do not significantly help prevent dental disease since the small kibble is minimally chewed when eaten. 

If you decide to change your cat's food, it is best to do so slowly.  One reason is to help prevent vomiting or diarrhea.  Another reason is that some cats do not accept change easily and may go on hunger strike which can lead to its own health problems such as fatty liver disease.  The switch from free feeding dry food to meal feeding canned food takes time since cats will object to not having food available at all times.  If you decide to help your overweight cat lose weight, remember that a cat should not lose more than 1 to 2% of its body weight per week.  Most cats need 150 - 200 calories per day.  Although typical cat foods do not list the calories (kcal) on the label, usually you can find this information on the internet.

Remember to drop off your food donations to the PAWSitively CATS shelter at 3432 E Fort Lowell in Tucson, Monday through Saturday from 10am-2pm.