Kidneys are very important because they remove waste substances from the blood, and maintain the normal balance of fluid and minerals within the body. Once kidney damage occurs, the consequences are usually irreversible. 
Because the right nutrition can positively impact your pet's quality of life, Hill's, nutritionists and veterinarians developed Prescription Diet® k/d®, clinical nutrition especially formulated to support your cat's kidney health. In fact, k/d is clinically tested to improve quality of life in cats.