Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: For pets with kidney disease, the key is limiting phosphorus while still providing enough high-quality protein to maintain muscle. Prescription kidney diets do this for you. If your vet approves extras or a nutritionist designs a home-cooked diet, lower-phosphorus protein options include egg whites and some lean meats in controlled amounts, while organ meats, bones, dairy, and processed meats are high in phosphorus. Always check with your vet before adding anything to a kidney diet.
Why phosphorus matters
- Failing kidneys can’t clear phosphorus well
- High phosphorus speeds kidney damage
- Protein is still needed to prevent muscle loss
Lower-phosphorus protein options (with vet approval)
- Egg whites
- Small amounts of lean cooked chicken, turkey, or beef, depending on your pet’s plan
- Treats made from your pet’s renal diet
Higher-phosphorus foods to limit
- Organ meats (liver, kidney)
- Bones, bone broth made with bones, and bone meal
- Cheese and dairy
- Jerky and dried meat treats
- Processed meats with phosphate additives
- Whole fish with bones, sardines
Important cautions
- Adding protein to a renal diet can undo its phosphorus restriction
- Homemade kidney diets should come from a board-certified veterinary nutritionist
- Cats need enough protein. Severe restriction causes muscle loss
More: kidney diets for dogs and kidney diets for cats.
Sources
- International Renal Interest Society (IRIS): Treatment recommendations
- Merck Veterinary Manual: Chronic kidney disease in small animals
- WSAVA Global Nutrition Committee: Nutrition toolkit
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.