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Calcium and phosphorus are essential minerals for strong bones and teeth, and, in healthy cats, they generally remain in balance. Cats with kidney disease aren’t always so lucky.
The kidneys are responsible for excreting waste products including excess protein and phosphorus in the form of urine, so conditions like chronic kidney disease (CKD) may not only impact the function of this essential organ, but also phosphorus levels in the body.
Many veterinarians recommend a low-phosphorus diet for cats with kidney problems, but what exactly does that look like? In this article, we’ll explore this subject and provide you with our top picks for the best cat food low in phosphorus.
Understanding Kidney Disease in Cats
In a healthy cat, the kidneys help eliminate excess protein, balance electrolytes, and produce urine. When the kidneys’ abilities to perform these functions become compromised, it leads to acute or chronic kidney disease which can then progress to kidney failure.
Here’s an overview of acute versus chronic kidney disease:
- Acute Kidney Disease – Often caused by abrupt injury to the kidney and may cause urine production to stop entirely, often leading to death.
- Chronic Kidney Disease – Characterized by a slow decline in kidney function, resulting in mild signs of illness and dehydration that can worsen over months or years.
Early signs of kidney disease include increased thirst and urination as well as subtle weight loss. As the disease progresses, some cats may experience decreased appetite, more severe weight loss, lack of energy, and poor grooming habits. With fluid treatment and a healthy diet, cats can recover well and live a long life after kidney disease as long as it’s caught early.
What to Look for in Low Phosphorus Cat Food
In addition to fluid therapy and, in some cases, medication, your cat may benefit from a low-phosphorus diet to reduce kidney workload and speed recovery. In fact, research shows that cats with chronic kidney disease fed a low-phosphorus diet can live twice as long as cats with no dietary changes.
Cats with severe kidney disease should consume less than 100mg of phosphate per 100kcal while cats with mild to moderate kidney disease can tolerate up to 250mg per 100kcal of phosphate.
Here are some other things to look for in low-phosphorus cat food:
- Moderate protein content (between 28% and 35% dry matter basis)
- Low carbohydrate content (less than 20% of calories)
- Limited dietary phosphorus (between 0.3% and 0.6% dry matter basis)
- Supplemental omega-3 fatty acids to reduce inflammation (0.4% to 2.5%)
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 his moisture intake, but this isn’t a scientifically supported fact.
Now that you have a better understanding of your cat’s kidney disease and how to support his recovery with low-phosphorus cat food, let’s take a look at our top picks.
The Best Cat Food Low in Phosphorus
The best cat food for kidney disease will reduce kidney workload by moderating protein, carbohydrate, and phosphorus intake while increasing intake of moisture and omega fatty acids. If you choose to feed your cat dry food, make sure he drinks plenty of water and consider adding some wet food to supplement his moisture intake.
Here are our top picks for the best cat food low in phosphorus:
Available in both dry and wet food forms, this veterinary diet is a high-quality and nutritious option in low-phosphorus food for cats from a trusted brand.Buy Now on Amazon for $7.99 per lb
This 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.Buy Now on Chewy for $4.24 per lb
Produced in a human-grade food manufacturing facility, this super-premium canned food recipe is low in fat and phosphorus but rich in high-quality animal protein from fresh chicken.Buy Now on Amazon for $8.51 per lb
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.Buy Now on Chewy for $8.73 per lb
In addition to feeding your cat a low-phosphorus diet, you might also want to include kidney-supporting supplements like treats made with natural herbs to support immune function and boost circulation to the kidneys.Buy Now on Amazon for $11.26 for 120 chews
Tips for Homemade Low Phosphorus Cat Food
Many prescription diets formulated for kidney support are made with meat by-products, fillers, and other low-quality ingredients. This being the case, a homemade diet may be the best option for some cats with moderate to severe kidney disease.
Here are some tips for creating a homemade diet for cats with kidney disease:
- Choose a protein naturally low in phosphorus like rabbit or poultry
- Include egg whites as a supplemental source of protein low in phosphorus
- Formulate the recipe to contain between 28% and 35% protein by dry matter basis
- Aim for a phosphorus content between 0.3% and 0.6% with sodium below 0.4%
- Consider adding fish oil supplements to increase the omega-3 fatty acid content
Before changing your cat’s diet (especially if you’re switching to a homemade cat food), but sure to consult your veterinarian to ensure that your cat’s nutritional needs are met.