Ask the Vet: Diet for Cats with Kidney Disease
“I have a kitty dealing with renal challenges (Sandy Paws). I have had her successfully on Sub Qs (every 4 days) and a great Omega oil. Please render any other recommendations you may have...she is 10 or 11 years old, and just holds at about 7.1 pounds.”
Answer: More than ever, it seems, many pets are suffering from kidney (renal) damage and failure. This is partly due to last year’s pet food recall that harmed so many pets (whose kidneys will never fully recover) but kidney disease was already common, especially in older cats.
In cats, kidney disease develops for two main reasons:
Being fed only or mostly dry food, which is extremely dehydrating and puts a great burden on their kidneys. Even though you’ll see these cats drinking water, they make up only half the intake a cat eating a canned, raw or homemade diet would take in.
Receiving unnecessary booster vaccines for feline distemper (panleukopenia). The virus in this vaccine is commonly grown in a culture of feline kidney cells. When the vaccine is injected, kidney proteins from the culture fluid cause antibodies to form against them; these antibodies cross-react with the cat’s own kidneys and sets up a low-grade chronic inflammation. Every repeated booster worsens this inflammation, eventually leading to cell destruction, scarring, and ultimately kidney failure.
The same potential problems apply to canine vaccines. All vaccines are grown in some type of cell culture; canine, feline and calf cell cultures are commonly used. One study showed that every vaccinated puppy produced antibodies that cross-reacted with its own tissues, including red blood cells and connective tissue such as collagen.
Low-protein diets are commonly prescribed for kidney failure. The real reason for this is because meat is high in phosphorus, and it is phosphorus that is the problem (it combines with calcium and further damages the kidneys). However the scientific support for this treatment is much stronger for dogs than for cats. It is also important to remember that high protein diets do not cause kidney disease.
The quality of the food is also extremely important. Most “prescription” and “veterinary” pet foods are made from very poor quality ingredients: by-products, grains, and meat substitutes. Since these animals already have health issues, it makes more sense to feed them the very best natural ingredients. Most high-quality commercial foods have fairly high levels of protein, so a home-made diet may be your best option. Here’s a couple of sample recipes:
For Cats: - 1/4 cup chopped or ground chicken breast - 1 cup cooked white rice (long-grain or basamati) - 1 Tablespoon Omega-3 fish oil - 1/8 teaspoon salt substitute (potassium chloride) - 500 mg calcium (tablet or capsule without magnesium, vitamin D, or bonemeal) - 1/4 human multiple vitamin-mineral tablet - 250 mg taurine
For Dogs (per 20 pounds of body weight): - 1 large chopped hard-boiled egg - 2 cups cooked white rice (long-grain or bassamati) - 1 Tablespoon Omega-3 fish oil - 500 mg calcium (tablet or capsule) - 1/2 human multiple vitamin-mineral tablet or capsule
Certainly, getting these animals off dry food is a crucial component because it’s vital to keep these pets well-hydrated. Giving subcutaneous (“sub-Q”) fluids at home is also a great help with hydration issues, and can offset some of the negative effects of higher protein.
Several supplements are proven to be helpful in renal disease. Omega-3 fatty acids are very important. It should come from wild fish (not farmed salmon) and contain mostly or only Omega-3s. Omega-6s promote inflammation, which is of course not what you want. Antioxidants will also help manage and decrease inflammation.
Recent research suggests that adding extra probiotics to the diet helps with protein metabolism and minimizes the metabolic by-products of protein digestion (blood urea nitrogen or BUN, and creatinine) that would otherwise enter the blood and cause toxicity. Digestive enzymes are also beneficial because they break down proteins earlier in the digestive process.
For more detailed information, see: Kidney disease in cats and dogs
Preventing kidney failure is a whole lot easier than treating it, so if you have young, healthy pets in your home as well, make sure they are on an excellent natural diet (canned, raw, or homemade); appropriate supplements including probiotics, antioxidants, digestive enzymes, and Omega-3 fatty acids; and minimize vaccines.