Your cat’s been diagnosed, and your vet has likely recommended Hill’s Prescription Diet Kidney Care (k/d) in the hope of keeping your cat in the best health possible.

You’re probably here to find out if that’s true, but as you read this review you’ll probably learn some harsh truths. Please don’t feel bad though, as I went through the same with my first cat Rodney 20 years ago.

Let’s find out the truth about Hill’s Prescription Diet and how it may support kidney health in your cat:

Hill’s Prescription Diet Kidney Care (k/d) for cats

What the marketing says

Caring for your cat’s kidneys should start when they’re a kitten, but unfortunately we have the wool pulled well and truly over our eyes for one simple reason – pet food marketing.

On the packaging of Hill’s Prescription Diet Kidney Care dry food we find the words “VETERINARIAN RECOMMENDED” in bold letters. We also find claims like “CLINICAL NUTRITION”, “THERAPEUTIC CAT NUTRITION”, and “S+OX SHIELD” whatever that means.

You’ll also find some French, something about an “Enhanced Appetite Trigger” or “E.A.T”, and a cute cat. They also say “With Chicken”, which according to the American Standard for Manufacturing and Marketing of Pet Food means somewhere between 5% and 20% of the formula.

But what does all this really mean?

A cat, by definition, is an obligate carnivore. Meat eater through and through.

Let’s take a look at how “carnivorous” the ingredients of this cat food are, but let the following quote sink in first:

Cats are desert animals. In their native environment the source of moisture available to them is from their diet – prey animals – particularly from the intestines and kidneys. This is why drinking from a bowl is unnatural for a cat. Domestic cats fed dry food will often suffer from a lack of moisture intake, as a precursor to renal failure.

An American certified pet nutritionist (name redacted).

When you consider these essential facts, it may make you wonder if dry food was the cause of their current kidney problems in the first place. Or whether a dry food labelled “Kidney Care” is the real remedy?

What the ingredients really say?

Chicken is the first ingredient.

Sounds great, doesn’t it?

But, remember I mentioned the with word meaning 5% to 20%? That means the next ingredients will likely be most of the food, and that matters.

What we find in Hill’s Prescription Diet Kidney Care for cats is brown rice, corn gluten meal, and whole grain wheat. That’s not the last of the grains either, with more inclusions of brewers rice, wheat gluten, and soybean oil.

Ask your vet if they think grains are good for cats.

In fact, this cat food has 38.2% carbohydrates listed on the label, which will mostly come from the wheat and rice. The protein will be inflated with corn, which doesn’t seem ideal for a meat-eating cat.

For a brand marketed as a veterinarian-endorsed or “science diet”, have they forgotten the true nature of the animal they’ve designed this food for?

To make matters worse, these grains are cooked into a fairly moisture-less dry kibble, supposedly to support your cat’s kidneys!

It makes you wonder why vets recommend such a brand, even if it does make them a lot of money.

The best argument I’ve heard from vets over the years is they’ve seen this cat food work. But the real question is why, and my best guess is because the previous cat food was worse.

Yes, there’s additives in the food to support your cat’s kidneys, but the truth is you’re feeding your carnivorous cat a laundry list of grains.

Surprised?

My first cat was diagnosed with early stages of renal failure, and on my vet’s recommendation we fed him this food until he passed away. He withered away long before that though, and I had to medicate him to the eyeballs and extract poo from his anus. Poor guy.

If I were you I’d opt for a diet with significantly more meat, preferably with organs too, and definitely more moisture. A cat water fountain may be a good investment, but why not feed them a carnivorous diet with natural moisture instead? Raw, wet, or fresh foods will likely be better.

I hope this review helps you make a choice for your cat which really leads to better health.

I don’t ask much in return, but if this review has helped, or helps your cat, please take 30 seconds to leave me a positive review on Google – this really helps support this website! You can leave a review here.

Questions on a postcard (or in the comments section below).

If you’re determined to feed a Hill’s Prescription Diet for kidney care, then I urge you to feed the wet canned variety. It’s much more appropriate for a cat with kidney problems.

Where to buy

Ingredients

Ingredients of Hill’s Prescription Diet Kidney Care (k/d) cat food:

Chicken, Brown Rice, Corn Gluten Meal, Whole Grain Wheat, Chicken Fat, Brewers Rice, Pea Protein, Chicken Liver Flavor, Powdered Cellulose, Egg Product, Wheat Gluten, Soybean Oil, Fish Oil, Lactic Acid, Calcium Sulfate, Potassium Citrate, L-Arginine, Calcium Carbonate, L-Lysine, Choline Chloride, DL-Methionine, L-Threonine, vitamins (Vitamin E Supplement, Niacin Supplement, L-Ascorbyl-2-Polyphosphate (source of Vitamin C), Thiamine Mononitrate, Pyridoxine Hydrochloride, Calcium Pantothenate, Riboflavin Supplement, Biotin, Vitamin A Supplement, Vitamin B12 Supplement, Folic Acid, Vitamin D3 Supplement), Taurine, Potassium Chloride, Iodized Salt, minerals (Ferrous Sulfate, Zinc Oxide, Copper Sulfate, Manganous Oxide, Calcium Iodate, Sodium Selenite), L-Carnitine, L-Tryptophan, Mixed Tocopherols for freshness, Natural Flavors, Beta-Carotene.

Guaranteed analysis

Guaranteed analysis of Hill’s Prescription Diet Kidney Care (k/d) cat food:

* May be estimated. Read how to calculate carbohydrates in a pet food.

But does it fix the problem?

What is the real problem your dog has?

It may not be as complicated as you think.

If you haven’t read the ingredients of Royal Canin Hypoallergenic, then I think you’ll be surprised… or a little miffed.

Royal Canin Hypoallergenic review

What the marketing says

When your vet recommends a brand it’s easy to trust their advice as a professional, and trust the brand without considering what you’re actually paying for. I was guilty of this myself almost 2 decades ago, and these products haven’t changed much since.

You would also expect a brand like Royal Canin, especially the “Veterinary” range, to be backed by bucket loads of science and research. In reality we can use some basic facts about our dogs to raise some ominous questions, and it doesn’t take much digging.

You may be wondering why your vet would recommend such a brand if it wasn’t “good”, but there are simple reasons for this. A key reason is they’ve seen it “work”. Royal Canin Hypoallergenic works – it will alleviate your dog’s symptoms – but why.

Don’t worry, I’ll tell you why shortly. Once you know, finding a suitable dog food will be easier than you think – I’ve known this to be the case on countless occasions. After all, you don’t want to be locked in to an expensive veterinary dog food, do you?

To start with, a better term to “allergy” is a food “sensitivity”. If your dog has been showing symptoms of a food sensitivity then it is very likely something in your previous dog food. Is this something you’ve considered?

It’s quite possible the ingredient wasn’t appropriate for a dog anyway, which is often true for many dry dog foods.

Let’s take a look at the ingredients of Royal Canin Hypoallergenic.

What the ingredients really say

You may consider your dog an omnivore, because that’s what we’re often told. Many people these days consider them carnivores – they’re from the Order Carnivora after all. Wherever you believe your dog sits on this scale doesn’t really matter, as I’m sure you know they love meat.

The main ingredient in Royal Canin Hypoallergenic is rice. Not nutritious brown rice either, but bog standard cheap white rice.

Rice probably doesn’t strike you as a staple ingredient for your meat-eating pooch, but the benefit to your dog is it’s not “allergenic”.

But what about protein? The stuff that keeps your dog healthy, supporting their muscles and organ health?

This isn’t from meat either, instead being hydrolysed soya protein isolate, so processed soya. Hydolysed means the soya protein has been broken down using hydrolysis to make it more digestible, but you have to question the benefit to your dog of processed soya protein over meat proteins which are by default easy to digest.

These two ingredients will be most of the food. Does that make you wonder why you’re paying so much for rice and soya for your dog?

But it’s “science”, so you still trust it. Those clever boffins at Royal Canin know what they’re doing, right?

Perhaps it’s more about profit margins than your dog?

Did I mention Royal Canin is made by Mars, one of the world leaders in profiting from consumers?

The remaining “main” ingredient is animal fat, which although better for a dog is very ambiguous. Fat from what animals?

Compare these ingredients with other premium dog foods and you may wonder what you’re paying for.

What you really should consider

Let’s get back to your old dog food. Did it contain wheat, cereals, cereal by-products? If it did, I bet that’s your problem.

Wheat is problematic for dogs as they struggle to digest it. Cereals are usually worse, and will likely be wheat anyway. As for by-products of wheat… well, you can guess.

Chicken is also a common cause of allergies and sensitivities in dogs, or beef, or perhaps lamb. Your dog may only react from those meat proteins cooked, or sometimes only raw.

Chicken is the trickiest sensitivity because it’s in most dry dog foods regardless of “flavour”. Even a “Beef” formula may contain chicken, chicken fat, or even “animal fat” can be chicken. Confusing, isn’t it?

Don’t worry, there’s some great recommendations on the hypoallergenic dog food page which don’t contain any of the above ingredients. Limited ingredient dog foods may also be a good starting point, as these are designed for this specific reason.

Your best way forward is to find out exactly what is causing the reaction in your dog. Vital information!

Related: Hypoallergenic dog foods | Royal Canin dog food review

Where to buy?

If you’re still keen to feed your dog Royal Canin Hypoallergenic, even if it’s in the short term, there these should be the best prices:

Ingredients

Ingredients of Royal Canin Hypoallergenic dog food:

Rice, hydrolysed soya protein isolate, animal fats, hydrolysed poultry liver, beet pulp, minerals, soya oil, fish oil, fructo-oligo-saccharides, borage oil, marigold extract (source of lutein). Protein sources: hydrolysed soya protein isolate, hydrolysed poultry liver. Carbohydrate source: rice.

Additives (per kg)*: Nutritional additives: Vitamin A: 27500 IU, Vitamin D3: 800 IU, E1 (Iron): 42 mg, E2 (Iodine): 3.8 mg, E4 (Copper): 15 mg, E5 (Manganese): 55 mg, E6 (Zinc): 154 mg, E8 (Selenium): 0.26 mg – Technological additives: Clinoptilolite of sedimentary origin: 10 g –  Preservatives – Antioxidants.     *Values reflect levels added to the formula, not those naturally occurring in components of the diet.

Analytical constituents: Protein: 21.0% – Fat content: 19.0% – Crude ash: 6.1% – Crude fibres: 1.1%, essential fatty acid (Linoleic acid): 2.47% – EPA/DHA: 0.33% – Omega 3 fatty acids: 0.95%.

Guaranteed analysis (not guaranteed?)

Most good dog foods have a “guaranteed analysis” which assures you of minimum amounts of protein and fat – the stuff that matters to your dog. Some cheaper brands opt for a “typical analysis” which means percentages can go either way, usually not in your dog’s favour.

Royal Canin use the clever wording “Analytical Constituents”, which is likely a clever way of saying “typical analysis” without saying “typical analysis”.

Guaranteed analysis of Royal Canin Hypoallergenic dog food:

* May be estimated. Read how to calculate carbohydrates in a pet food.