I’ve talked many times before about the important role that balanced nutrition plays in keeping our pets healthy. In fact, there aren’t many things that owners do on a daily basis that have a greater influence on their pets' well-being.
However, eating healthy and balanced food can be more than just a way to prevent problems; dietary intervention is an often underutilized method of managing disease. A classic example of this is chronic kidney disease. But first, let me go over a little kidney physiology so that I can more easily explain what kidney diets accomplish.
One of the kidneys' major roles is to excrete waste products of metabolism out of the body. One of these waste products is urea, a toxic substance formed when proteins are broken down, which veterinarians can measure in the bloodstream in the form of blood urea nitrogen (BUN). When kidney function declines past a certain point, BUN levels start to rise. Higher than normal levels of urea in the bloodstream — a condition known as azotemia or uremia — can make animals feel terrible.
Now back to the diet. Since urea is formed when proteins are broken down, carefully controlling the protein content of a dog or cat’s food can influence how much urea they make. If they make less, they have to excrete less. Even if kidney function remains the same (and sometimes it actually improves with a dietary change), less urea builds up in the blood stream and pets feel better.
That said, kidney diets can’t be too low in protein. The goal is to meet the body’s needs while not overburdening the kidneys — a real balancing act. The proteins that are included in a kidney diet should also be of high quality so that they can be well utilized by the body and not simply broken down and excreted as waste. But protein isn’t the only nutrient that plays a role in kidney disease. Kidney diets have other characteristics (e.g., low phosphorous and sodium levels) that can improve kidney function and help pets feel better and live longer lives.
With mild to moderate kidney disease, feeding a special diet may be all that is needed to keep pets feeling healthy and functioning well. However, as kidney disease gets worse, most pets will require fluid therapy and medications in addition to a special diet to maintain their quality of life.
It’s important to note that kidney disease isn’t the only health concern that responds to dietary management. Therapeutic diets can also be helpful in the nutritional management of diabetes mellitus, heart disease, food allergy/intolerance, liver disease, skin problems, hyperthyroidism, joint disease, cancer, weight issues, dental disease, brain changes associated with aging, lower urinary tract disease, gastrointestinal conditions, or when a pet is recovering from an accident, illness, or surgery.
Talk to your veterinarian about whether a therapeutic diet might be in your pet’s best interest.
Dr. Jennifer Coates