- This post contains affiliate links. Read more here.
- Not a substitute for professional veterinary help.
Coming to grips with a kidney disease diagnosis for your cat can be tough. Take a deep breath. Keep in mind that when chronic kidney disease is spotted early, your cat may have many more years to enjoy. However, extending their life will require a diet of cat food low in phosphorus.
Three out of 10 geriatric cats (age 15 or older) will receive a diagnosis of chronic kidney disease. My deaf white cat, Sheba, was diagnosed at age 14 and she went on to spend more than four more happy years chasing the other cats in our household and swatting vases off the mantelpiece. Don’t lose hope!
In this article, we take a look at chronic kidney disease in cats (also called chronic renal failure) and the low-phosphorus diet for cats recommended by many veterinarians to slow the progression of kidney disease.
Understanding Kidney Disease in Cats
Kidney disease in cats can be caused by a bacterial infection, but often the exact cause remains unknown. For whatever reason, your cat’s kidneys stop doing their job of removing waste products, such as proteins and phosphorus, and excreting them in urine. As a result, the cat’s systems are thrown out of balance and all sorts of problems occur, from high blood pressure to anemia. This page from The Cat Doctor in Seattle goes into all the details.
What are the first signs of kidney disease? Your cat may show increased thirst or begin urinating more frequently. Though they eat normally, you may see subtle weight loss. As the disease progresses, some cats may experience a decreased appetite, more severe weight loss, lack of energy, and poor grooming habits.
Kidney disease is not curable, but if the condition is caught early on, a healthy diet can enable cats to live a long life. As the condition progresses, cats may be given phosphorus-binding drugs before meals, subcutaneous fluids, and other medications. But let’s start with the food.
Why Get a Cat Food Low in Phosphorus?
A low-phosphorus diet is designed to reduce kidney workload and improve health. Research shows that cats with chronic kidney disease fed a low-phosphorus diet can live up to twice as long as cats with no dietary changes.
This video from Cornell University College of Veterinary medicine explains in detail how special low-phosphorus “kidney diets” work to decrease stress on your cat’s renal system.
Increasing your cat’s water intake is also important to support the kidneys’ abilities to excrete waste products through urine. Feeding your cat canned food may help boost their moisture intake, but this isn’t a scientifically supported fact. You’ll need to provide your cat with clean, fresh water at all times. At some point your vet may suggest that you give subcutaneous fluids.
The best cat food for cats with chronic kidney disease will reduce kidney workload by moderating protein, carbohydrate, and phosphorus intake. Because poor kidney function allows acids to build up, kidney diets are alkaline, helping to neutralize harmful acids.
“Kidney diets are actually very different from regular cat food,” explains Dr. Joe Wakshlag, veterinarian and professor at Cornell University College of Veterinary Medicine in the Cornell video. “They have reduced levels of phosphorus and protein and they have increased levels of potassium, B vitamins, and fatty acids.”
The Cornell experts advise introducing low-phosphorus cat food to your cat gradually by mixing it in with their regular food. Over time, your cat can be switched to the low-phosphorus diet. If the cat tires of one brand of low-phosphorus food, the experts advise trying another one for variety. In reviews of these foods, most owners report that their cat suddenly changed its mind about what food it liked and didn’t like. You may find yourself trying all of them!
(Note: Cats with chronic kidney disease should not be fed foods labeled as “urinary diets” unless recommended by your veterinarian. Those are designed to prevent the formation of kidney stones—a very different condition—and can even aggravate kidney disease.)
The Best Cat Food Low in Phosphorus
Now that you have a better understanding of your cat’s kidney disease and how a cat food low in phosphorus can help, let’s take a look at our top picks.
You’ll find two types of low phosphorus foods on our list:
- Prescription veterinary diets with carefully calibrated amounts of phosphorus, sodium, protein, minerals, vitamins, and fatty acids. These are usually alkaline rather than acidic foods.
- Low phosphorus foods that include premium, natural ingredients but do not claim to address the range of kidney issues that prescription foods are designed to treat.
If you look at food ingredient labels, you’ll notice that many of the low phosphorus prescription formulas do not necessarily include organic meats and they are rarely grain-free. If you want to feed your cat an organic diet or a grain-free diet, you may have to make a choice between non-prescription low-phosphorus foods and feeding your cat what is essentially a prescribed medicine for their health condition.
We include both prescription kidney diets and non-prescription low phosphorus foods on our list. You’ll want to check with your vet to see what they recommend for your specific cat. Note that you’ll have to provide a prescription or your veterinarian’s contact information to purchase the prescription foods from Chewy.
Because cats with kidney disease tend to lose weight, Royal Canin has formulated this low phosphorus pâté in gel to be as tasty and enticing as possible. It can be combined with any of Royal Canin’s non-prescription food or offered on its own. In addition to the pâté, Royal Canin makes other renal support formulas including D (morsels) and T (slices) and it’s worth experimenting to see if your cat prefers one over the others.
Available in both dry and wet forms, this grain-free veterinary diet from Blue Buffalo is a high-quality and nutritious low phosphorus and low-sodium food for cats, from a brand that focuses on preservative-free natural ingredients.
This prescription diet is designed to protect kidney and heart function while boosting your cat’s energy and vitality with targeted levels of high-quality protein and controlled phosphorus.
This specially formulated wet food contains a moderate amount of high-quality protein and restricted phosphorus. It can be combined with the kibble version of this diet if your cat enjoys dry food. Purina also makes an Advanced Care formula.
This low phosphorus non-prescription recipe is made with 15% fewer calories to support ideal body weight but is still made with fresh, natural ingredients including several premium animal proteins like chicken, salmon, and duck.
This grain-free beef-and-pumpkin recipe is low in phosphorus and sodium, making it a healthy option for cats with kidney disease. It’s not a veterinary kidney disease formula—check with your vet to make sure it meets their standards. If your cat is turning up their nose at some of the prescription foods, this could be a good choice to keep them interested in eating.
If your kitty is looking for something new in a low-phosphorus food, this pâté might spark their interest. Many Chewy reviews say this got their cat interested in food again. Though it is called “veterinary select,” it’s not a veterinarian prescribed diet, and you can buy it without a prescription.
Produced in a human-grade food manufacturing facility, this grain-free canned food recipe is low in fat and phosphorus but includes high-quality animal protein from chicken.
Tips for Homemade Low Phosphorus Cat Food
Because cats with moderate to severe kidney disease may become picky eaters, a homemade diet may be the best option for your kitty. This PetMD article cautions against grabbing a recipe off the internet, even if it’s touted as being great for a cat with kidney failure. Instead, they advise consulting with a veterinarian or a credentialed veterinary nutritionist—they’ll have a recipe or two that will be safe and effective for your cat.
Featured image via IRCat/Pixabay