3 Best Cat Food For Kidney Disease

Disclaimer: As a Chewy, Pet Circle and Amazon affiliate, I earn from qualifying purchases. This does not impact our best cat food for kidney disease review.

The best food for cats with kidney disease is a low phosphate prescription cat food.

This type of cat foods helps slow kidney disease progression and improves lifespan.

Kidney disease is common in senior cats. It’s progressive and decreases lifespan if not treated.

In this article I’ll go through what kidney disease is in cats and how to tackle it with diet. Then, I’ll go through my best rated picks (including non-prescription choices) for you to look at.

Finally I’ll answer any frequently asked questions on the topic of kidney disease in cats.

What is Kidney Disease in Cats?

Kidney disease involves a progressive loss of kidney function in cats.

It’s common in older cats, affecting over 30% by the age of 15. Some experts suggest it’s even higher, with 30% cats affected at 10 years and 81% at 15 years.

Either way, it’s kidney disease is generally an age related issue in cats.

The symptoms of kidney disease in cats include:

• Increased thirst
• Frequent urination
• Weight loss

The kidneys filter waste products (e.g. nitrogen from protein metabolism) from the blood to the urine. Kidney disease causes waste products to build up (called azotemia).

Why are waste products bad? They can cause unpleasant problems like nausea, vomiting and fatigue.

The disease can also lead to loss of protein (proteinuria) and water, resulting in muscle loss and dehydration.

Veterinarians use the International Renal Interest Society (IRIS) criteria to characterise kidney disease into stages.

This system uses plasma creatinine (measure of kidney filtration rate) to help grade the severity of the disease and guide treatment.

Why Choose Low Phosphorus Cat Food for Kidney Disease?

Choosing a low phosphorus cat food for kidney disease is important for several reasons including:

• Limiting phosphate retention: Kidney disease leads to phosphate retention because it isn’t being eliminated. This then leads to parathyroidism, which increases kidney damage.

• Increasing lifespan: A low phosphorus diet increases lifespan in dogs and cats with kidney disease. A kidney disease diet also reduces the risk of a uremic crisis (kidney failure).

• Reduced financial costs: Improving your cat’s health can help lower financial costs related to medical treatment.

The type of phosphate is important too.

Inorganic phosphate salts (e.g. sodium or potassium phosphate) are more bioavailable than meat and cereal phosphate. Cat food using these salts are worth avoiding.

How much you need to restrict phosphate will depend on the stage of kidney disease, so it’s best to consult with a veterinarian for specific advice on how restrictive you need to be.

What Food Should I Feed a Cat With Kidney Disease?

Prescription cat food is the best option for cats with kidney disease. 

These foods are designed to have lower phosphate than other commercial cat foods. This helps slow kidney disease and improve lifespan.

Prescription diets also have other nutritional features which help manage kidney disease (e.g. lower protein content).

Avoid mixing prescription with homemade or other commercial cat foods. Experts suggest this can introduce too much phosphate, which negates any benefit.

As a rule of thumb, limit other food and treats to no more than 10-15% of the diet.

Phosphate binders are an option if blood phosphate doesn’t go down with dietary treatment.

Here are more dietary factors that can help manage kidney disease:

High Omega 3

This type of fat is high in fish like salmon.

It helps reduce inflammation and may help preserve the kidneys. Omega 3 fatty acids may improve survival times for cats with kidney disease.

High Moisture

Water helps keep the kidneys moving.

This helps prevent the build up of waste by-products. Cats with stage 3-4 kidney disease are at a higher risk of dehydration from diuresis.

Wet cat food is preferable for kidney disease, in conjunction with strategies like increasing the amount of water bowls or using a fountain.

Constipation is common in elderly cats, which tend to also be afflicted with kidney disease. It’s important to help keep older cats hydrated to prevent this issue.

Moderate Protein Restriction

Moderate protein restriction can help reduce build up of protein metabolites in the blood, with benefits depending on stage of disease.

The restriction of protein is controversial, with research showing protein restriction doesn’t induce renal lesions when simulating kidney disease in healthy cats.

Renal diet formulas contain 6-7 g/100 kcal of protein, which is much less than the 9-10 g/100 kcal in many commercial cat foods. This works out to 28-35% protein on a dry matter basis.

Fortunately, the protein in renal cat food exceeds adult maintenance needs for cats (26% protein dry basis). That means it should be sufficient to help cats maintain muscle.

However senior cats, who make up a significant amount of kidney disease cases, require more protein for age related muscle loss.

To maintain muscle, healthy cats need at least 5.2g of protein per kg of body weight, with experts suggesting seniors need more (>40% protein dry basis).

Another problem is cats prefer high protein diets (~50% dry basis). This makes it challenging for cats to accept lower protein diets and can result in food rejection.

If your cat struggles with diet, it’s important to discuss strategies with your vet. Protein restriction might not be warranted depending on the stage of kidney disease.

High Calcium

Calcium and phosphate are the two major minerals in the body. Balancing them is essential for your cat’s diet, especially with kidney disease.

Experts suggest maintaining a calcium with phosphate ratio of 1:1. This helps prevent renal calcification, a problem where calcium deposits in the kidneys impairing their function.

Excessive phosphate with low calcium intake can cause renal secondary hyperparathyroidism.

This is a problem where the parathyroid glands become overactive, releasing parathyroid hormone. This hormone exacerbates calcium depositing in the kidneys and weakens bones.

High Potassium

Potassium is crucial to the health of cats, especially those with kidney disease.

At least 20-30% of cats with kidney disease will have hypokalemia, which is a problem of low potassium in the blood. 

Symptoms of hypokalemia include:

• Constipation
• Muscle weakness
• Increased urination.

Renal diets are generally fortified with additional potassium to prevent this. If required, your vet may use potassium gluconate or citrate as supplements to increase potassium.

Low Sodium

A low sodium intake may help slow the progression of kidney disease.

Diets with 290 mg/100 kcal sodium have been shown to increase waste products in the blood of cats with renal insufficiency, demonstrating a potential strain on the kidneys.

However, the evidence for low sodium diets is lacking in other research and the diet is hard to implement.

High Fat

Fat is the most calorically dense nutrient.

That makes it a great source of energy for cats with low appetite and/or weight loss.

When choosing a cat food, consider opting for a prescription or kidney appropriate cat food higher in fat if weight maintenance is a problem. 

It’s worth noting that cats prefer moderate fat diets, making them more palatable options. Fat is also helpful for senior cats, who tend to have impaired fat digestion.

High in B Vitamins

B vitamins are a group of essential nutrients that help with metabolism.

These nutrients are water soluble. That’s important because kidney disease can increase thirst and urine production, leading to a loss of water-soluble nutrients.

Renal diets are supplemented with vitamin B as are cat foods formulated as complete and balanced meals. For that reason, B vitamins aren’t an issue unless you feed your cat homemade or supplemental cat food, which both lack these nutrients.

Low Phosphorus Wet Cat Food Chart

This chart contains a list of low phosphorus prescription and non-prescription wet cat foods.

Most of the information was sourced online and through this report here. The information might not reflect recent price and recipe changes.

Wet Cat Food for Kidney Disease	Cost per ounce	Prescription	Kcal/kg	Protein (%)*	Protein (g)	Phosphorus (%)	Phosphorus (mg)	Calcium (mg)	Potassium (mg)	Sodium (mg)	Vit D (IU)	Omega 3 (mg)
Royal Canin Feline Renal Support D	$0.86	Yes	1,149	30-46	6.8	0.6	80	130	190	80	17.8	150
Purina Pro Plan Veterinary Diets NF Advanced Care	$0.48	Yes	1,059	26	6.7	0.5	90	160	370	80	24.8	110
Royal Canin Feline Renal Support T	$0.86	Yes	969	26-45	6.6	0.7	100	160	190	100	26	140
Hill’s Prescription Diet kd Feline with Tuna	$1.01	Yes		23	6.6		104	174	247	56	26.3	140
Hill’s Prescription Diet kd + Mobility Chicken & Vegetable Stew	$0.95	Yes		29	6.6	0.5	108	198	234	54	43.4	180
BLUE Natural Veterinary Diet KM Kidney + Mobility Support	$0.47	Yes	978	20	6.1	0.4-0.9	110	160	560	50	55	150
Purina Pro Plan Veterinary Diets NF Early Care	$0.48	Yes	1,039	28	9.7	0.9	110	150	380	100	22.3	120
Hill’s Prescription Diet kd Feline Chicken & Vegetable Stew	$0.82	Yes		26	6.8		111	176	239	53	44.2	133
Hill’s Prescription Diet kd Vegetable & Tuna Stew	$0.82	Yes		24	7.1		115	193	247	57	36.8	145
Hill’s Prescription Diet kd with Chicken	$1.05	Yes		25	7.6		120	215	279	61	28.3	155
Royal Canin Feline Renal Support Early Consult	$0.86	Yes	964	34	8.4	0.8	120	160	180	90	17.8	170
Hill’s Prescription Diet k/d Early Support Chicken, Vegetable & Rice Stew	$0.80	Yes		38	7.6		133	198	210	61	31,5	174
Royal Canin Feline Health Nutrition Aging 12+ thin slices in gravy	$0.70	No	834	50	11		115	146	94	178	23	167
Royal Canin Feline Health Nutrition Aging 12+ loaf	$0.59	No	844	47	10.5		116	158	105	100	22.1	158
Weruva Truluxe Steak Frites	$0.70	No	844	62	10.5	0.6	118		178	57

3 Best Cat Foods for Kidney Disease

Best Cat Food for Kidney Disease Overall

Why Do I Recommend This Cat Food?

This is one of the lowest phosphate options on the market that I’ve found (it may be the lowest). With the moderate protein content it’s designed to help slow the progression of kidney disease.

The D stands for delectable. Most cats with kidney disease struggle with appetite when offered prescription cat food, due to the low protein content. This will help tackle that issue.

Like most prescription cat foods, it’s pricey so you’ll have to fork out for it. I have not tried this one personally, so I cannot comment on taste however customer reviews are generally positive.

Best Non Prescription Low Phosphorus Wet Cat Food for Kidney Disease

Weruva Truluxe Steak Frites

Why Do I Recommend This Cat Food?

I was recommended this product via email due to it’s kidney friendly low phosphate levels. The balance of calcium to phosphate is at 1:1 which supports it’s use as a non-prescription option.

Most customers report a great taste. We’ve tried Weruva products with our cats and enjoy the human grade appearance of their range (as did our cats).

Still, the high protein content is less optimal for late stage kidney disease if proteinuria is present.

Best Prescription Low Phosphorus Dry Cat Food for Kidney Disease

Royal Canin Veterinary Diet Adult Renal Support A

Why Do I Recommend This Cat Food?

For dry prescription cat food, I recommend Royal Canin (again) because it’s the lowest calorie choice and has top reviews. The A stands for aromatic, so this one can help tackle weight loss and low appetite.

Whilst I haven’t personally tested this one, I’ve used other Royal Canin cat foods and like the results I get compared to other big prescription brands. Our cats tend to enjoy them more than others.

The use of brewers rice as a main ingredient isn’t something that I like, but this is of course going to be a lower protein food to help manage kidney disease at more advanced stages.

Frequently Asked Questions

Can Healthy Cats Eat Renal Food?

Yes, healthy cats can eat renal food.

In a 2022 study, healthy cats were fed the same renal food as cats with kidney disease. This suggests cats can eat renal food without adverse effects, however this study only lasted eight weeks.

Renal food meets the minimum nutrition requirement for adult cats. A low phosphorus diet should start in adulthood to help prevent kidney disease.

Is Chicken Ok for Cats With Kidney Disease?

Yes, chicken is often used in prescription diet formulas and is safe for cats to eat. However, it is not appropriate as a sole source of nutrition for cats with kidney disease.

Chicken is a high protein food that can help cats with early stage kidney disease (IRIS stage 1 and 2) maintain weight and lean muscle mass. Cats enjoy the taste of meat as they are obligate carnivores.

The main issue with chicken is it’s high phosphate and low calcium. As a sole food source, chicken isn’t ideal as it leads to parathyroidism (which is already in issue in kidney disease).

Is Dry Food Good for Cats With Kidney Disease?

Yes, there are dry food kidney disease options that are good for cats with kidney disease.

One study showed an increase in body weight when cats with kidney disease were fed dry cat food.

A similar study on cats with stage 1 and 2 kidney disease showed that prescription dry cat food (Hill’s Prescription Diet k/d Feline with chicken) helped increase body weight and lean mass.

Since cats with kidney disease can become dehydrated, it’s important to offer enough water when feeding dry cat food.

Is Canned Tuna Good for Cats With Kidney Disease?

No, canned tuna isn’t good for cats with kidney disease. It is not a complete and balanced source of nutrition.

What Not to Feed a Cat With Kidney Disease?

Avoid feeding cats with kidney disease high phosphate and protein diets. Most adult cat maintenance cat foods aren’t recommended, and instead you’ll want a renal cat food.

Research shows that not adjusting diet increases progression of the disease and risk of mortality.

What Foods Help Repair Kidneys?

Kidney disease is a progressive and experts consider it not possible to ‘repair’ the kidneys.

However, a prescription kidney cat food increases survival time in dogs and cats with kidney disease.

A kidney disease diet also reduces the risk of a uremic crisis (kidney failure). Improving your cat’s health also helps with financial costs related to medical treatment.

On the other hand, acute kidney failure is reversible if caught in time. This is a sudden drop in kidney function related to infection and/or medication.

What Are the Early Warning Signs of Kidney Disease?

One study identified a range of early warning signs of kidney disease including:

• Weight loss
• Dehydration
• Periodontal disease
• High blood pressure
• Heart disease
• Loss of appetite
• Vomiting
• Decreased activity

Ageing itself, is a risk factor so it’s important to have regular annual visits at the vet to stay on top of things.

How Long Can a Cat with Kidney Disease Live?

Disease progression is unpredictable.

Many owners may opt for euthanasia due to the time and financial burden of caring for a cat with kidney disease.

The prevalence of kidney disease increases with age.

10% of cats over 10 have kidney disease, which increases to 31% over 15.

Feeding your cat a kidney-protective diet improves the lifespan and health of your cat.

Is Wet Food Better for A Cats Kidneys?

Wet cat food has greater moisture content than dry cat food which helps prevent dehydration. However, dry cat food is more calorically dense and may help combat weight loss.

There is no ‘best’ option and it’s recommended you speak with your vet about which option is the ideal one for your cat.

Worst Cat Food for Kidney Disease?

Supplemental cat food is the ‘worst’ cat food for kidney disease as it doesn’t contain the balance of nutrients cats need. Homemade cat food is also a problem if not well formulated.

Be weary of homemade recipe advice on the internet. Almost all recipes don’t meet a cats needs and aren’t well designed for kidney disease.

What Treatments Do Cats With Kidney Disease Need?

Treatments include:

• Dietary therapy
• IV fluids
• Medication (e.g. phosphate binders)

Speak with your vet to find the proper treatment for your cat.

Treatment depends on The International Renal Interest Society (IRIS) stage of the disease.

Diet modification is important to slow the progression of kidney disease.

What Breed of Cat Is Prone to Kidney Disease?

Breeds at a higher risk of kidney disease include:

• Maine coons
• Abyssinian
• Siamese
• Russian blue
• Burmese
• Persians

Speak with your vet for more information.

How do I Introduce a Kidney Disease Food?

Introduce new food slowly.

Cat’s have neophobia, which means an aversion to new foods. It takes time to adjust your cats taste to new food.

There are two approaches to introducing new food:

1. Placing the food next to old food side-by-side in the same bowl
2. Mixing with the old food

Start by adding a small amount to the old food. Increase over 4-8 weeks.

Warming food to room temperature helps improve the smell and taste.

Conclusion

A low phosphate prescription food is recommended to treat kidney disease in cats. This type of food slows disease progression and improves lifespan.

Other factors like moderate protein restriction and increased calcium intake may also help offer benefit to cats.