Conscious Cat

October 17, 2011 37 Comments

Kidney Failure and Diet in Cats

Posted by Ingrid

cat eating bowl

Guest post by Darren Hawks, DVM

Renal insufficiency, or kidney failure, is very common as our cats age. Early signs are subtle, seen only as increased drinking and urination. More advanced signs are weight loss, poor appetite, vomiting, and dull coat. Problems occur as the kidneys can no longer reabsorb water, leading to excessive urination and chronic dehydration. As problems progress, the kidneys cannot handle the breakdown products of excess protein, leading to the buildup of toxins in the blood (azotemia). This is reflected in an increased BUN and creatinine on blood work.

The goals of therapy for renal failure are to increase hydration, decrease the buildup of toxins in the blood, treat any possible underlying reversible disease (infection, hyperthyroidism), maintain good blood flow to the kidneys, and minimize any further damage.

Diet is a key component of the health program for a cat with kidney disease, but the goals may not be quite what you have been told. In my opinion, the most basic first step in mild to moderate cases is to increase water consumption. This means avoiding dry food (the reason here being that cats on dry food tend to be chronically dehydrated, but there is another important reason regarding protein sources which we will discuss in just a bit). Fresh or frozen unprocessed food, or as a second choice canned food, should be the diet of choice. Many cats with mild to moderate disease will improve with this step alone.

Secondly, the source of protein in the diet is crucial. Blood toxicity (uremia) from kidney failure occurs because toxins are created when excess protein is broken down. The amount of dietary proteins which is used to satisfy basic body protein needs does not create these toxins, but dietary protein in excess of these needs do. Different protein sources have different types of amino acids, and if the composition of amino acids in the food do not match the needs of the body, the unused ones must be broken down, thus creating toxins.

The goals are not only to provide just enough protein to meet needs, but also to provide the correct ratio of amino acids so that the unusable amino acids do create toxins. This means matching a cat’s protein and amino acid needs with its food. Cats are pure carnivores, and their amino acid requirements are those found in MEAT. Not corn meal. Not soy. Not by-products as the sole source of protein. MEAT. This may go against conventional wisdom, but it really does make sense.

Find a food that is based on meat, not carbohydrates. Interestingly, this means fresh or canned, since all kibbles will have a higher carbohydrate content. So you will solve two problems, high water content and high quality protein with one diet.

What about protein restriction?

There is some controversy regarding protein restriction for cats with kidney disease. First and foremost, there is no evidence that protein restriction prevents kidney disease in healthy cats. There is also no solid evidence that protein restriction prevents further damage to cats with existing kidney disease. What protein restriction might do is help decrease the amount of toxins (reduce azotemia or decrease BUN) so that your cat feels better. But there is still controversy there, too, despite what your veterinarian might tell you.

In my opinion, there are no clinical studies showing conclusive benefit of protein restriction in cats with renal failure. I am not saying that there is no benefit, just no conclusive proof of benefit, meaning that we just do not know for sure. Even experts agree that the degree of protein restriction possible in cats is somewhat limited by their higher protein requirements. My advice to you would be to try a protein restricted diet only if your cat is not doing well and see if improvement is noticed.

All veterinarians will agree that eating something, anything, is better than not eating (the body will digest its own muscles, which is the highest protein diet possible and obviously not good for the body), and some cats will not eat a protein restricted diet.

Let me put in a plug for my diet recommendations. I much prefer fresh food to processed food. This would usually be in the form of homemade diets (please, please be sure to follow a respected recipe!) or commercially prepared frozen diets. These can be fed raw (after you have educated yourself on the feeding of raw foods) or lightly cooked.

Another option is ZiwiPeak, an air dried meat formula with minimal processing. In my opinion, this would be the next best to fresh food, better than canned or kibble. ZiwiPeak has the advantage of containing organ meat in proportions to that found in nature, along with omega 3 fatty acids of animal source. It is also convenient, with no worries associated with the handling of raw foods.

If canned food is your choice, then I would recommend the ZiwiPeak canned foods. As with the entire ZiwiPeak line, the canned food has free-range meats with no added hormones or antibiotics. The meat comes from a consistent, New Zealand known source. The ratio of meat to organs is that found in nature, mimicking what a pet would eat in nature. All of these are important factors when choosing your pet’s food.

Advanced cases of kidney failure might require a lower protein diet, but a meat based diet is my preference for mild to moderate kidney problems in cats. You can be guided by your cat’s appetite, weight and energy levels. Try the lower protein diets if your cat is having problems and see if you notice an improvement. Please note that the BUN of a pet on a meat-based diet can be higher than that of a pet on a grain-based diet and still be normal and healthy.

Since the goal is to supply only the needed amount of protein, fat is often the other part of the equation to supply calories (rather than simple carbohydrates). Cats do metabolize fats better than people and dogs, so the higher fat content is usually not a problem. High quality fats, however, might be hard to find. Processed fats (exposed to the high heat and temperatures associated with canning) can cause free radical damage and inflammation. Thus we are back to fresh, frozen or air dried diets as the better choice.

Speaking of fats, one of the additional recommendations for cats, dogs, and people with renal insufficiency is to include omega 3 fatty acid supplements in the diet. Omega 3 fatty acids decrease inflammation and help maintain blood flow to the kidneys. Cats do require an animal source for some needs, so think about krill or fish oils.

Other alternative therapies include glandulars (supplements containing actual kidney tissue along with supportive nutrients; Standard Process products would be an good example), homeopathic remedies, and Chinese herbs.

Subcutaneous (SQ- under the skin) fluids can be an invaluable, life-prolonging therapy which can be provided at home (ask your veterinarian). Check for possibly treatable underlying conditions such as hyperthyroidism (blood test) or kidney infection (urine culture). Minimize vaccinations to only that which is truly needed, and space them out rather than giving them all at one time. Consider testing antibody titers instead of automatically giving vaccines. Excessive stimulation of the immune system with vaccines can result in antigen-antibody complex settling out into kidney tissue, causing inflammation and further compromise in kidney function.

Potassium supplementation is often a good idea in cats with kidney disease, as overall body depletion can occur even if blood levels of potassium are normal. You can talk with your veterinarian regarding available supplements.

Darren Hawks, DVM graduated from the UC Davis School of Veterinary Medicine in 1988. She is a board certified specialist in internal medicine. She offers a variety of alternative therapies including chiropractic, other manual therapies (myofascial release, Integrative Manual Therapy, Reiki), herbs, homeopathy, flower essences and nutrition. Her goal is to guide owners towards a total health program including diet, exercise, improved energy flow via body/energy work, removal of stress and toxins, as well as addressing emotions and stress. For more information about Dr. Hawks, please visit her website.

Ziwi Peak offers a complete range of ultra premium natural meat pet products prepared with care beneath the Bay of Plenty’s celebrated peak, Mount Maunganui, New Zealand. For more information about Ziwi Peak and their products, please visit their website.

Editor’s note: Dr. Hawks was compensated by Ziwi Peak for this article. Always consult with your cat’s veterinarian before making diet changes or giving supplements.

Photo: morguefile.com

Dr. Goodpet

 

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37 Responses to “Kidney Failure and Diet in Cats”

  1. Generally a good article, but he did not mention about the importance of limiting phosphorus in the diet of cat with renal disease. Although cats with renal disease have the same protein requirements as any other cat, it can be important to limit meat based protein as they are higher in phosphorus,and it might be appropriate to use egg as a protein or a high quality plant protein. The other option is to add a phosphorus binder like IPAKITINE.

    • Ingrid says:

      Thank you for pointing out the issue of phosphorus, Michael. I believe that Ipakitine is called Epakitin in the US, and there are several other products available as well. It should be noted that phosphorus binders should not be given without checking with your veterinarian.

  2. Marg says:

    Thanks for this post. It was very informative. I just went and gave Holly some potassium. Great post.

    • Ingrid says:

      Marg, make sure that potassium supplementation is indicated for Holly – check with your vet first. Excess potassium can cause serious heart problems.

  3. Evelyn says:

    Excellent article! Thank you, Dr. Hawks!
    (I would like to note, however, that Dr. Hawks is female.)

  4. Very informative post. Thanks!

  5. Robin Olson says:

    Good timing on your article, but bad news for us as we struggle with learning our cat Nicky has early signs of CRF. I agree that protein has to be fresh, raw meat, which is what Nicky gets now and will continue to be fed as we learn more about his condition. I’ll definitely share this informative post. Thank you, Ingrid!

    • Ingrid says:

      I’m so sorry about Nicky, Robin. You’re already well-versed in raw feeding, but if you’re looking for a veterinarian who can help you formulate a raw diet for a cat with kidney disease, I highly recommend Dr. Lisa Pierson.

  6. Good post on a way too common issue with cats.

    • Ingrid says:

      Sadly, it is a very common issue, Layla. I think we need to ask ourselves why that is the case. I’m convinced that diet, especially dry food, plays a significant role in the prevalence of kidney disease in cats. Unfortunately, there just aren’t any studies that have looked at this issue.

  7. Wan-Ju Jao says:

    Thanks for the post!

    This is what I’m doing for my cat now. His creatinine is almost 3.0 but BUN falls in the normal range. My cat has been feeding Ziwipeak (dry food) for a long time but he started to vomit after meal recently. So I switch his food to cans and he is doing fine now. Do you know anything about “Nutripe” canned foods? They are also grain-free and meat based canned foods. Just want to know are they good enough for cats with kidney problems. Thank you!

    • Ingrid says:

      Wan-Ju, I’m glad you’re seeing an improvement after switching your cat to canned food. I’m not familiar with the “Nutripe” brand.

      • Melissa says:

        Hi Ingrid, thanks so much for the informative blog post! I have the same question as Wan-Ju regarding Nutripe – here’s the nutritional analysis (I used the Venison formula because Ziwipeak has a comparable Venison one; both brands are free range and grain free formulas from New Zealand):

        http://www.nutripe.com/catcanned-08.php

        Ingredients:
        Venison (with heart, liver & lung), Chicken, Ocean Fish, Tripe, Stabilizer (Carrageanan, Guar Gum), Vitamins & Minerals, Green Lipped Mussel Powder, Taurine, Sufficient Water for Processing

        Typical Analysis
        Crude Protein (min) 10.45%
        Crude Fat (min) 5.25%
        Crude Fiber (max) 0.4%
        Crude Ash (max) 2.3%

        This is in comparison with Ziwipeak Venison:

        Ingredients: Venison – Meat, Liver, Tripe, Kidney, Green-Lipped Mussel , Carageenan, Guar Gum, Sodium Tripolyphosphate, Vitamins (Thiamine Mononitrate, Riboflavin, Nicotinic Acid, Vitamin E Supplement, d-Calcium Pantothenate, Vitamin B12 Supplement, Pyridoxine Hydrochloride, Folic Acid, Vitamin D3 Supplement), Minerals (Zinc Sulphate, Ferrous Sulphate, Manganese Sulphate, Copper Sulphate, Sodium Selenite, Potassium Chloride), Taurine, DL-Methionine

        Typical Analysis:
        Crude Protein 10.0%
        Crude Fat 7.0%
        Crude Fibre 2.0% (max)
        Moisture 78% (max)
        Ash 2.0% (max)
        Calories 1100 kcal/kg
        Calcium 0.54%
        Phosphorus 0.39%

        I think the Ziwipeak one will have slightly less carbohydrates – which is a very good thing! However, the Nutripe is comparable… and for half the price, it’s a good alternative. What do you advise?

  8. Pam says:

    I use the ZiwiPeak air-dried food for my dogs … my cat enjoys RadCat raw meals 100% of the time.

    As for the ZiwiPeak canned foods, what about the carrageenan? I have heard conflicting things about carrageenan, and I now choose to avoid it altogether, since I don’t know what is true about carrageenan.

    I notice that on the ZiwiPeak website they have a section under the FAQs about carrageenan. They state that the form they use is safe.

    It’s hard to know what’s true about carrageenan.

    • Ingrid says:

      Pam, I don’t know what to tell you about carrageenan. There’s a lot of conflicting information about it and some of it does concern me.

      I haven’t tried the RadCat brand for my girls, but it’s on my list of brands to try – I like what I’ve read about it.

  9. Sandy says:

    I have a 6 month old kitten, she has elevated BUN levels 44 urine sp gr:1.107 alb 4.1 creatine is in normal levels. Ultra sound diagnosis. Probable Familial Renal Failure. One vet said low protein diet. Another her regular wants her on Science Diet kitten, What would you suggest? I sure do not want to lose her

    • Ingrid says:

      I’d lean toward your regular vet’s suggestion, Sandy, except I don’t like the Science Diet products at all. They contain too many by-products as well as corn and soy. I’d look for a premium, all meat brand of either kitten food or just regular grain-free canned food. Once you choose one, run it by your regular vet to make sure he feels that protein levels are adequate. As you can see from the article, protein restriction is usually not indicated until the final stages of renal disease, and it’s especially tricky in a growing kitten.

  10. Tamara says:

    Hi Ingrid, I read your post with great interest because lately I have been noticing a very strong ammonia smell in my cat’s litter-box and I was wondering if maybe his kidneys may be suffering. The problem is that with him being an indoor cat in a high-rise, I really don’t want to vaccinate him (he had his initial round of vaccines a little over a year ago) but my vet will not see him unless he has the full battery of vaccines .I know you will probably suggest going elsewhere but I get the feeling this will probably be a requisite of other vets too in my area.I prefer to take him to a nearby vet because he gets very anxious and carsick when traveling and I want to spare him long trips. He is 4 years old and is being fed Wellbeing weight control dry food because he is about 16 lbs. I have on occasion tried to feed him wet food but he doesn’t want it.I did use a different brand of litter in his litter-box for a few days because I didn’t have time to go to the usual place I go to (PETCO) to refill his litter bucket so I just bought some litter in the convenience store in my apartment building,so perhaps the smell could be due to that. I am just trying to be cautious here.What can you suggest?
    Thank you so much,Tamara

    • Ingrid says:

      You’re absolutely right, Tamara, I’m going to tell you to find a vet who will see your cat without current vaccinations. :-) Look for a holistic vet in your area, or a housecall vet – that might be even better, since your kitty gets car sick. It’s possible that the new litter caused the different smell in the box, but I’d err on the side of caution and get him checked out. I’d also wean him off the dry food completely. You’ll find lots of information about why, and how to do it, in the Feline Nutrition section on this site. I hope this helps!

  11. Michelle says:

    Could anyone share a few raw recipes that I could use for my older cats? I have 3, (ages 11, 11, 14) and they are all currently eating Purina U/R (the oldest cat needed it to help with sludge). I agree that a raw diet would be better. I really wish I had known more about raw diets previously. But if anyone could suggest some recipes, or a resource to get them, I would appreciate it.
    Michelle
    UC Davis grad just like the author, but unfortunately not a Vet :)

    • Ingrid says:

      I can’t recommend any raw recipes specifically for cats in renal failure, Michelle, but I believe Dr. Lisa Pierson can do a remote consult and help you formulate the right diet for your cat. Her website is http://www.catinfo.org. Balanceit.com may also be able to do it for you.

      • Michelle says:

        Thanks. I happily just signed up for the blog. I should have done a little more poking around before posing a question, as clearly there is a lot of info already here. Thank you! Look forward to reading more.

  12. Ellen says:

    Thank you for the article. I wish I’d read it 6 years ago when my Silver was diagnosed.
    I trusted my vet, put him on KD, did the SubQ fluids and he died quickly and painfully in less than 3 months after $1000’s in vet bills & diagnosis.
    After I recovered, I adopted my neighbor’s 12 year old feral (but indoor) cat. And, I found out she also had kidney disease. SubQ fluids were out of the question – the vet had to sedate her just to get a blood sample. He gave her 9 months at the most, and suggested KD. I said no thank you. I fed her good canned food, good low carb/zero grain dry food pre-wet with warm water, and LOTS of of fresh water. At the end, she would only drink low salt chicken stock. But, she got better in the first 6 months, started running around and playing like a kitten. She lived a total of 2 years. She never did let me pick her up, but she would occasionally sit in my lap & ask to be pet. She died a much happier cat than my poor Silver.
    Thanks for the excellent article & posts!

    • Ingrid says:

      I’m sorry about Silver, Ellen. Your formerly feral kitty’s progression of the disease certainly is a testament that the right diet can make a big difference!

  13. Nancy says:

    Our Bambi-Sue is 18 years old next month. She has been treated for CRF since JULY 2009! She will only eat dry food, the vet said to give her whatever she likes. She likes dry Fancy Feast Filet Mignon and crunchy treats. Nothing wet or canned for this princess. She gets sub fluids every 3.5 days (for the last 3.5 years) at the vet’s office. She’s slowing down, still drinking lots of water, and sleeps a lot during the day. We have to help her get on the bed or into my lap, but she is a lap kitty and is quite happy there, especially in a cool room. Not so much when the AC comes on, and it is warm in NC about 8 months out of the year. She is well taken care of by our vets at Wake Veterinary Hospital, they are our heroes!

    • Ingrid says:

      The most important thing for any cat in renal failure is to make sure that she eats. I’m glad your Bambi-Sue has been doing so well despite the fact that she won’t eat wet food.

  14. Martin says:

    My Birman is 12 years old has been diagnosed with third stage kidney disease. He has always been on Hills T/D and diced beef from the butcher. I have been told to get him off the Hills T/D and he is on Renal biscuits that he doesn’t eat. He loves dried chicken treats but wants them all the time now. I don’t know what do to.

  15. sam maben says:

    Is it too late to start a 15yr old cat on a raw meat diet? She has Kidney Disease

  16. Could anyone direct me to a respected recipe for a homemade cat food for our cat with renal failure?
    He still eats and drinks quite well, but is less active, loosing condition, has an estimated 25% kidney function and could be anything from 9-13yrs old (he was a rescue cat).
    We live in rural Australia and a one-on-one dietary consult is not offered by any specialists in our area.

    Gratefully yours,

    Liz and Roscoe cat.

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