A low protein diet for dogs can be a crucial therapeutic tool when prescribed and monitored properly, especially for managing kidney and liver issues under veterinary guidance. This specialized nutritional approach requires careful consideration and professional guidance to ensure it meets your pet's needs while addressing specific health concerns. Understanding when low protein diets are necessary, their benefits and risks, and how to implement them safely under veterinary supervision is essential for pet owners faced with decisions about their dog's dietary needs.
Understanding Low Protein Diets for Dogs
A low protein diet for dogs is specifically designed to reduce the workload on certain organs, particularly the kidneys and liver. These specialized diets typically contain 18% or less protein, compared to regular adult dog food that usually contains 25-30% protein. The primary goal is to minimize the accumulation of protein-related waste products while still providing essential nutrients for basic bodily functions. This balance is crucial for managing specific health conditions without compromising overall health.
Medical Conditions Requiring Protein Restriction
Several medical conditions might require a dog to go on a low-protein diet, such as kidney disease, liver disease, and some kinds of bladder stones.
Kidney Disease
Chronic kidney disease (CKD) is one of the most common reasons for prescribing a low protein diet. Reducing protein intake helps decrease the kidneys' workload and slows the progression of the disease by minimizing the accumulation of nitrogenous waste products. Upon diagnosis of CKD, a veterinarian may wish to flush the kidneys to remove toxins, which can help resume normal kidney function.
Liver Disease
Dogs with liver disease may benefit from protein restriction because a compromised liver struggles to process protein waste products, particularly ammonia. Controlling protein intake helps prevent hepatic encephalopathy and other complications.
Read also: Canine Kidney Diet: Ingredient Breakdown
Urate Bladder Stones
Urate bladder stones, which account for only 6 percent of all bladder stones found in dogs, can be addressed by switching the dog to a low-protein diet specially designed to dissolve the stones. In this case, the diet wouldn’t be permanent.
Implementing a Low Protein Diet Safely
Success with a low protein diet depends on careful implementation and monitoring. Consider these essential factors:
- Regular veterinary check-ups to assess effectiveness
- Proper transition from regular to low protein food
- Monitoring for signs of protein deficiency
- Ensuring adequate essential amino acid intake
Quality vs. Quantity in Protein Restriction
The quality of protein sources in a low protein diet is just as important as the quantity. High-quality, easily digestible proteins help maximize nutrient absorption while minimizing waste products. This approach ensures your dog receives essential amino acids even with reduced protein intake. Fresh, high-quality (organic is best!) protein in the form of meat is recommended.
Monitoring and Adjusting the Diet
Regular monitoring is crucial when feeding a low protein diet. Watch for:
- Changes in energy levels
- Muscle mass maintenance
- Coat and skin condition
- Appetite and weight changes
- Overall vitality
Pet owners should also be monitoring their dog’s weight and body condition to be sure their dog isn’t inappropriately losing or gaining weight due to his new diet.
Read also: Managing Canine Lymphoma with Diet
Risks and Considerations
It’s very important to feed a diet still containing protein, however. Feeding too little can cause muscle wastage, slower healing from injury, cognitive inabilities, and slower metabolism.
Conventionally Trained Vets and High Protein Diets
Vets are used to examining the blood results of animals fed minimum protein diets and conventionally trained vets learn that the liver and kidneys may no longer function when protein rises in the blood. Protein is a valuable bioindicator of what might be happening under the hood.
However more and more people are starting to feed their dogs like the little meat-eaters they most certainly are, to the great benefit of their health. This means a diet of lots of protein and a little fat (for example, a rabbit, should you suck all the water out of him, is perhaps 70-80% protein and 10% fat. While many pre-made raw dog foods produce excellent products to this protein: fat ratio, many of the cheaper brands (and indeed our mixes we make ourselves) are usually a little fattier.
Compare this natural diet to cereal-based dog food. These animals exist on a diet of 18-22% protein, the minimum you can use in pet food, and state it is “complete by AAFCO standards.” The rest of these products are cereal, with around 50-60% carbohydrate. These are two very different feeding styles, one getting lots of protein and the other the minimum required.
It should thus come as no surprise that when their blood is tested, raw-fed dogs have significantly more protein in their blood, around 20-30% more. This high blood protein rings alarm bells for your conventionally trained vet who has been using for their comparison laboratory dogs fed standard, cereal-based diets, food that is desperately low in protein. Of course, dogs fed a slightly more luxurious diet containing more meat always risk appearing to have “excessive levels of protein in their blood,” but this is not because they are sick; it’s just because they’ve been eating more.
Read also: Diet for Seizures in Dogs
The theory from dry food manufacturers and the vets they educate is that this extra blood nitrogen risks creating an additional load on the kidneys, as they need to filter all this “excess protein” from the blood. So your vet then reaches for the low-protein dry food to try and control this rise. It makes sense, doesn’t it?!
Is There a Time When Dogs with Kidney Disease May Need Low Protein?
The theory above has a tiny bit of weight in that one or two instances in treating human kidney disease where low protein is recommended. These are just before beginning dialysis (after which they are advised to increase their fresh protein intake to normal levels afterward, something dogs can’t do anyway) or if you have proteinuria (very dangerously high blood urea nitrogen, which in dogs is a BUN level of 80. This is rare and an indication that the dog is in the very end stage of kidney failure and severe trouble. So, yes, low protein at this time is sound advice). But what of every dog in between this?!
Studies Show Higher Protein Diets are Better
Studies show that even with their kidney function reduced by 90%, dogs do better on higher protein diets. Somewhat unsurprisingly, as meat eaters, studies show dogs thrive on high protein diets (Robertson et al. 1986, Bovée 1991, Finco et al. 1994, Hansen et al. 1992, Laflamme et al. 2008). Moreover, their ability to process the protein is so efficient that before feeding them the high-dose protein diets, many of the studies authors cited above actually removed 75% (and as much as 90%) of the kidney function in healthy dogs (by chopping off the supply to the rest of the organ), to replicate chronic kidney failure. All these studies unequivocally prove that dogs with CKF can safely deal with and do better on higher protein diets than on low protein dog food.
“…renal function and biochemical responses to dietary changes were studied in four dogs with stable chronic renal failure. The objective was to determine if dogs with moderate stable failure adjust to diets with varied protein and electrolyte content. These dogs were found to have the capacity to adapt to a wide range of dietary protein and electrolyte intake. The only exception was found in dogs fed a reduced-protein diet, which failed to appropriately adjust renal tubular excretion of sodium and phosphate. The only advantage of reduced dietary protein in this study was a reduction in blood urea nitrogen (BUN). The disadvantages of reduced-protein diets were reduced glomerular filtration rate (GFR) and renal plasma flow.” Bovée 1991
Concerns About Dry Food
Dry food companies illuminate the front of their food bags “clinically proven to benefit kidney disease in dogs.” But unfortunately, there is no mention of the study on the bag. Were they talking about dogs in proteinuria whereby a lower protein diet might have helped? Or are they reducing the salt content of their kidney food which would instantly make the kidneys happy? Or is the food more digestible? Or less antigenic somehow? Maybe it’s wheat free; that’d be nice. Or perhaps the manufacturer who conducted the trial in-house put the decimal point in the wrong place, and the food didn’t help. What we’re missing is actual evidence. It’s worrying our vets are not asking for this.
Now it happens that protein is expensive compared to carbohydrates. This is why most dry dog foods include so much cereal. By incriminating protein, they can consist of even more cheap carbohydrate filler. Crystals aside, all these carbs convert to sugar in the blood, which is balanced by lots of insulin. Excess insulin and soon insulin resistance contribute to the metabolic syndrome that is associated with the development of kidney disease too. It’s all so wrong.
Protein Levels and Kidney Disease Stages
Chronic Kidney Disease, abbreviated to CKD, happens in 4 stages. At this stage, there is no build up of toxins in the bloodstream, unlike in later stages. With often normal blood and urinalysis results, dogs with stage 1 kidney disease often have no clinical symptoms.
During stage 2, toxins begin to build in the blood, and the kidneys begin to lose their function. When the kidneys begin to decline, they often begin to leak protein into the urine, which would give a higher protein reading in a urinalysis than is expected of a healthy individual.
Once the diseased has progressed to stage 3, clinical symptoms are common, and include excessive drinking and urination. Due to the degradation of the kidneys at stage 4, both protein and creatinine levels are high.
Protein Type and Quality
Not only does the amount of protein consumed affect the kidneys, but also the type, and quality of protein.
The Role of Phosphorus
When the kidneys are damaged, they struggle to remove phosphorous from the blood. Studies show that greater excretion of phosphorous in the urine reduces the risk of cardiovascular disease. When looking at bone and tooth health, we need to consider the calcium-phosphorous ratio. When these are balanced properly, they work together to form strong bones and teeth, and help keep them in tip-top condition. Unfortunately, when there is an imbalance, and there is too much phosphorous in the body, calcium is pulled from the boned and teeth.
Low-Protein Dog Food Options
When selecting a low-protein dog food for your pup, consider the following factors:
- Protein content - Look for a formula with protein levels recommended by your vet, usually less than 18%.
- Fat content - Higher fat can make up for lower protein but avoid high fat for dogs with pancreatitis.
- Nutrition - Make sure the food offers complete, balanced nutrition even with less protein.
- Flavor - Pick flavors your dog gets excited for to keep them interested in eating.
- Price - Prescription low-protein foods can get pricey so also look at high-quality over-the-counter options.
- Individual needs - Factor in your dog’s age, activity level, breed size and health issues.
Some examples of low-protein dog food include:
- Hill's Prescription Diet k/d Kidney Care with Chicken Canned Dog Food - 9% protein
- Purina Pro Plan Veterinary Diets NF Kidney Function Dry Dog Food - 13% protein
- Royal Canin Veterinary Diet Canine Hepatic Dry Dog Food - 12% protein
List of Low-Protein Dog Foods
Here are 10 top-rated options:
Purina Pro Plan Veterinary Diets NF Kidney Function
- Protein content: 13%
- Key benefits: Restricted protein and phosphorus for kidney health
- Pros: Veterinarian recommended, excellent for picky eaters
- Cons: Expensive compared to regular dog food
Hill’s Prescription Diet k/d Kidney Care Chicken & Vegetable Stew Canned Dog Food
- Protein content: 7%
- Key benefits: Help improve kidney function with low protein and fat
- Pros: Palatable chicken and veggie flavor most dogs love
- Cons: High moisture content means you may need to feed more cans
Royal Canin Veterinary Diet Renal Support D Dry Dog Food
- Protein content: 10.2%
- Key benefits: Low phosphorus plus omega-3s for kidney health
- Pros: Kibble texture easier for some dogs to chew
- Cons: Contains corn and wheat some dogs are sensitive to
Purina NF KidNey Function Canned Dog Food
- Protein content: 11%
- Key benefits: Water-rich food to promote hydration for kidneys
- Pros: Very affordable price for prescription low-protein food
- Cons: Quality of ingredients not as high as pricier brands
Hill’s Prescription Diet k/d Kidney Care with Lamb Canned Dog Food
- Protein content: 7%
- Key benefits: Clinically proven nutrition to improve kidney function
- Pros: Many dogs love the tasty lamb and rice recipe
- Cons: High sodium content compared to some kidney formulas
Blue Natural Veterinary Diet Kidney + Mobility Support Potato & Duck Recipe
- Protein content: 12.5%
- Key benefits: Limited phosphorus and protein for kidney health
- Pros: Whole potatoes and duck provide natural sources of carbs and protein
- Cons: Higher price tag than regular Blue dog foods
Dave’s Pet Food Restricted Protein Chicken Recipe
- Protein content: 10%
- Key benefits: No corn, wheat, soy or by-products
- Pros: Uses human-grade ingredients
- Cons: Limited availability in pet retail stores
Nature’s Recipe Easy to Digest Rice, Barley & Salmon Meal Recipe
- Protein content: 14.5%
- Key benefits: Probiotics and easy-to-digest carbs for sensitive stomachs
- Pros: Affordable price for over-the-counter low-protein formula
- Cons: Higher protein content than prescription kidney care foods
Holistic Select Weight Health Chicken Meal & Pea Recipe
- Protein content: 16%
- Key benefits: Lean protein and fiber to help dogs feel fuller
- Pros: Made in the United States with no recalls
- Cons: May not be low enough in protein for kidney disease
Nutro Wholesome Essentials Senior Chicken & Brown Rice Recipe
- Protein content: 14%
- Key benefits: Low-fat and natural source glucosamine for senior joints
- Pros: Budget-friendly price for senior dogs
- Cons: Contains chicken by-product meal