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Diet and Nutrition

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More than you ever wanted to know about Feline Nutrition

One of the most common questions a veterinarian is asked is what to feed a cat. Everyone knows that diet plays an important role in their cat’s overall health, but few know what to do about it. There is no single best way to do this for all cats. What helps one cat may harm another. As each cat is an individual, specific recommendations will vary from cat-to-cat. Still, there are several general ways to improve your cat’s diet.

On a basic level, consider what stage of life your cat is in. Is he a kitten? An older, inside cat? This can help determine broad categories of dietary requirements. Very young kittens just starting out on solid food won’t be able to eat dry food very well. They’ll do much better on canned food specifically formulated for kittens. A young-to-middle aged adult cat will be fine on dry adult cat food. Some older cats need a geriatric or “senior” diet with fewer calories and protein. If they have dental problems, they may also do better on canned food.

Most of these diets can be bought at grocery and pet stores. Once in the store, how do you decide? One safe bet is to stick with national brands of pet foods. They are more likely to adhere to strict quality control standards. Read the labels and choose diets that meet Association of American Feed Control Officials “AAFCO” guidelines. These are minimum guidelines for quality pet food. Better still are diets that claim to be “evaluated by feeding trials,” which prove to work as intended. The “guaranteed crude analysis” of protein, fat, fiber content, etc. is of limited usefulness. It just describes the total amount of each components of the diet and not how much is available for digestion. Theoretically, a diet could have a high crude protein content composed of largely indigestible ingredients. This would leave little protein available for the cat to absorb, the equivalent of a  low-protein diet. Also, beware of diets claiming to be suitable for “all stages of a cat’s life cycle.” It’s not possible to make a diet suitable for a kitten that would also be optimal for an adult cat. Kittens need kitten food, adults need adult cat food.

One ingredient  worth special mention is “ash”. It causes a lot of confusion among cat owners. Ash is literally a measure of the amount of cinders left after burning the diet to a crisp! It consists of all inorganic components of the diet, primarily minerals. Many clients equate a high ash content with a diet inappropriate for cats with urinary tract problems. Nothing could be further from the truth. Cats need minerals as essential nutrients on their diet. So where did this come from? Many years ago, veterinarians discovered a relationship between cats fed high-ash content diets and those developing urinary tract obstructions. These cats were forming a particular type of bladder stone (called “struvite”) composed of magnesium, ammonium, and phosphorous. Later research showed that minimizing the amount of magnesium in the diet to no more than the actual nutritional requirement decreased the formation of struvite stones. It was the high levels of magnesium, not ash, that promoted struvite stone formation. Most labels do not state the magnesium content of their foods. Diets specifically formulated for “urinary tract health” are typically very low in magnesium and promote formation of a slightly acidic urine, which also decreases the formation of struvite stones. It’s very important to note, however, that there are other types of bladder diseases that will not be helped and could potentially be exacerbated by these diets. Use them only under a vet’s supervision. Although dry cat food has an increased ash content since it contains less water, it has no impact on urinary tract diseases.

While on the subject, let’s discuss the need for adding vitamins and minerals to the diet. Many years ago, when cat foods were marginal in comparison to today’s diets, this was a good idea. Today, most well known brands of cat food contain appropriate amounts of vitamins and minerals. Adding more will unbalance the diet and could cause medical conditions, such as bladder stones.

Giving treats to a cat is a bonding experience for cat and owner alike. Many cats live for the moment each day when they get their special treat. Treats add an ingredient missing from all cat foods: love. With the exception of obese cats and those with certain nutritional restrictions, treats can be given to all cats. Some treats are even helpful for promoting dental health, such as CET Chews. As with anything, however, give treats in moderation. Two or three a day is plenty. For those on special diets, try the other form of the food you now use (i.e., if feeding dry food, use a little bit of the same food in canned form). Even obese cats can have treats if they are low calorie. Try cantaloupe (really!) or other vegetables, or another form of their current diet food. We also carry low calorie treats.

Obesity is a common problem in cats and is one area where diet can dramatically affect their health. An additional pound for a cat is equivalent to fifteen pounds for a person! For an overweight cat, using low calorie diets in moderation will add years to their lives. Minimally reduced-calorie cat foods are available from pet stores (called “light” or “less active” diets). But for the truly obese cat, prescription diets are the only ones likely to be effective and must be used under veterinary supervision. These diets can usually be fed in normal amounts, since they are much lower in calories, so your cat won’t be hungry all the time.

There’s one other vital ingredient in a cat’s diet that’s often forgotten. Water is called the ingredient of life for good reason: you can’t live very long without it. Freely available, fresh water is all the liquid that most cats require. Remember that canned food’s main ingredient is water, so a cat eating only dry food will require significantly more water than one on canned diets. Also remember that running the furnace in a house will dehumidify the air so most cats drink a lot more in winter than summer. For this reason, we recommend using a humidifier during the winter. Older cats in general require more water than younger cats as they cannot concentrate their urine as well (it’s an age-related change in their kidneys). Also, there are certain medical conditions that will increase a cat’s water requirement, such as kidney disease, diabetes, and thyroid disease. Some cats prefer to drink running water. Rather than relying on someone to turn on the faucet, these cats do better with a water fountain. Plain or filtered tap water is sufficient for all cats. Bottled water is fine unless it contains high levels of dissolved minerals. For a cat with persistent bladder stones, distilled water may be helpful.

Finally, there’s one sure-fire way to improve your cat’s diet: ask us! Nutritional counseling is one of the cornerstones of sound medical practice. We will discuss diet during your cat's physical exam, but be sure to mention any concerns and questions you have. Here’s where these tips can be individualized for your cat. Just like different life stages dictate different diets, different diseases or medical situations dictate specific nutritional requirements. Some may be temporary, like pregnancy or surgery, and some may be life- long, like diabetes or kidney disease. Many, if not most, conditions can benefit from dietary changes. Annual Wellness Screening (a basic battery of lab tests) is an excellent way to modify and individualize a diet for your cat.

Cats are living longer and better lives because of advances in medical and nutritional care. Diet plays a vital role in your cat’s health. Simple things like choosing the right diet for your cat’s life stage have a huge impact on overall health. For more complicated problems, we can help you choose the best diet for your cat to ensure a long and better quality life.

Feline Nutrition Articles

Kitten Nutrition”by Marcella Durand, Home Again, 2004