Nutrition plays a key role in your cat’s health, and his urinary tract is no exception. If your cat is diagnosed with a urinary-tract disorder, such as kidney disease, feline idiopathic cystitis, bladder stones, or urinary-tract infections, your veterinarian may recommend switching to a urinary diet to help manage the condition and help prevent further problems. But there are many more factors that influence urinary health that you can monitor.

Hydration

Drinking enough water goes a long way toward protecting your cat’s urinary health. Dr. Richard Goldstein, DVM, former Cornell Associate Professor of Small Animal Medicine, advises, “We believe that at least 50 percent of a cat’s diet should be wet food.” Canned food contains more moisture than dry food, and so increases your cat’s daily water intake. This increased water intake flushes your cat’s urinary tract, thereby promoting good urinary tract health.

You need to be sure there is always plenty of fresh, clean water available that your cat can access easily. Some cats are more inclined to drink running water and will be attracted to a faucet left at a trickle or a kitty water fountain.

Urinary Stones

Stones form when there is a surplus of minerals in the cat’s urinary system. These excessive minerals form crystals, which can then clump together to form small stones.

Struvite and calcium oxalate crystals are the most common offenders, and struvite crystals can usually be minimized through a modification of diet. Struvites form in alkaline urine, so they often can be dissolved with an acidic diet. For cats with a history of struvite formation, feed diets that are limited in magnesium and that promote acidification of the urine.

Most of today’s commercial diets meet this requirement, so supplementation is usually not necessary (and making the body and urine too acidic can also cause problems). Animal-based proteins (such as chicken or beef) result in a more acidic urine, and DL-methionine is a common urinary acidifier added to many cat foods (DL-methionine is also an essential amino acid). Small, frequent meals can also help keep your cat’s urine in the healthy pH range.

Kidney Disease

Cats with chronic kidney disease (CKD) are often put on a kidney-friendly diet. These diets are usually low in protein, phosphorous, and sodium. The breakdown products of proteins and the concentrations of phosphorus and sodium are filtered and regulated by the kidneys, so having lower protein, phosphorus, and sodium in the diet can be beneficial to cats with CKD.

Be aware that other therapies—including phosphate binders, potassium, B vitamin, antioxidant supplementation, alkalinization therapy, and administration of fluids either intravenously or subcutaneously—have the potential to help cats with CKD. However, these approaches need more controlled studies to determine for certain whether they offer any benefits.

Sodium

Sodium may be added to some diets to encourage your cat to drink more water. While this may be effective for some cats, those with heart or kidney problems should not eat high-sodium diets.

Protein Source

Meat-based proteins keep the urine more acidic, which decreases the formation of urinary crystals and stones. Cooked egg whites are high in protein but low in phosphorous, so subbing in some cooked egg whites for part of your cat’s daily protein can be beneficial for cats with kidney disease who need decreased phosphorous in their diet.

Phosphorous

For cats with kidney disease, restricting dietary phosphorous can be beneficial. Choose a diet that is low in phosphorous or that includes phosphate binders, such as aluminum hydroxide, calcium carbonate, calcium acetate, sevalamar HCl, or lanthanum carbonate. Phosphate binders can be added if necessary.

Stress

Many signs of urinary-tract problems, such as inappropriate urination, can be caused by stress. In fact, stress has been implicated in the development of feline idiopathic cystitis. A cat who is unhappy about a new housemate or who is suffering from osteoarthritis may avoid using his litter box, causing strain on his urinary tract and resulting in urinating outside of the box.

The Cornell Feline Health Center cautions: “Many pet food manufacturers market diets formulated for ‘urinary health.’ While these foods may reduce the likelihood that cats with feline idiopathic cystitis will develop a urethral obstruction, there is no evidence that they have reduced the incidence of feline lower urinary tract signs themselves.”

If the underlying cause of your cat’s urinary problems is something physical, such as the formation and buildup of stones due to a nutrient imbalance, a diet change will help, but no food will be able to fix stress-related problems. Consider any major changes that have occurred in your cat’s life and make sure that there are plenty of litter boxes available in safe, quiet places.

Consistency

Changes in diet can sometimes cause a recurrence of FIC. So, if your cat’s health is stable, and he’s doing well on a certain diet, it may be wise to not rock the boat.

Weight Management

Whether your cat is eating a urinary diet or not, weight management is crucial to his health. Overweight cats are at a higher risk for a variety of diseases, including urinary tract problems. Feed your cat small, frequent meals, and encourage him to exercise and play. Institute weight-loss plans slowly and with the help of your veterinarian.

Prescription or Over-the-Counter?

No urinary diet food is one-size-fits all. Depending on the exact problem that your cat has, one food option may be better than another (for example, different diets are ideal for cats with urinary stones versus cats with kidney disease). If your veterinarian suggests that you switch to a urinary diet, don’t be afraid to ask questions to determine which qualities and ingredients are necessary for your cat to flourish on the new diet. Depending on your cat’s needs, there may be an over-the-counter option that will work or he may require a prescription diet.

Can All My Cats Eat the Urinary Diet?

In many cases, the answer to this question is yes, but it depends on the needs of your cats. If each of your cats has his own specific dietary needs, they may not all benefit from the same food.

Any food that you choose should have an AAFCO (Association of American Feed Control Officials) statement that the food meets the nutrient profile requirements for your cat’s life stage or for all life stages.

Ask your veterinarian to make sure that the urinary diet you are considering doesn’t conflict with any of the dietary needs of your other cats. If it does, you may need to monitor feeding times.

Urinary Tract Disorders in Cats

It’s wise to monitor your cat’s urinary health

Kidney Disease: This is the loss of function of the kidneys. Kidney disease can occur acutely or as a gradual, chronic progression. Cats often don’t show signs of kidney disease until there is significant damage to the kidneys. Kidney diets are usually low in protein, phosphorous, and sodium, and high in fiber, antioxidants, and water-soluble vitamins.

Feline Idiopathic Cystitis (FIC): This is an inflammation of the inner lining of bladder, which can make urination painful.

Kidney and Bladder Stones: Uroliths, or urinary stones, are a buildup of minerals that form in the bladder and/or urethra. Struvite stones can often be prevented by feeding an acidic diet that is low in magnesium. Calcium oxalate stones are generally less amenable to treatment with dietary modification.

Urethral Obstruction: When the urethra is blocked, either by stones or urethral plugs, little-to-no urine can exit the body. This causes the buildup of pressure within the urinary tract and wastes inside your cat’s body, which are medical emergencies requiring immediate veterinary consultation.