By Paula Fitzsimmons
For many dogs, an over-the-counter diet containing the proper amounts of protein, carbs, fats, vitamins, and minerals is adequate for maintaining optimal health. In some instances, however, your veterinarian may recommend a therapeutic diet for your canine companion. Obesity, food allergies, bladder stones, kidney disease, and neurologic disease are just some of the conditions that can be improved by special diets.
Why Your Vet Needs to Oversee Your Dog’s Therapeutic Diet
Therapeutic diets are prescribed and administered by veterinarians, and with good reason. For one, food and supplement manufacturers aren’t allowed to make claims that their products can prevent, treat, or cure illness, says Dr. Cailin Heinze, a veterinary nutritionist at Cummings School of Veterinary Medicine at Tufts University in North Grafton, Massachusetts. “To be able to make these claims without getting into trouble with the FDA, manufacturers of these types of diets have to limit their use only under veterinary supervision,” she explains.
Rules and regulations aside, it makes good sense for vets to supervise your dog’s therapeutic diet. “The disease being treated is something that requires veterinary supervision and without it, a misdiagnosis or mistreatment is likely,” she says.
And feeding a therapeutic diet to a dog who doesn’t need it can lead to problems. For example, “Kidney disease diets are low in phosphorus, which is not ideal for a healthy animal that doesn’t have kidney disease,” says Dr. Dan Su, a clinical nutrition resident at the College of Veterinary Medicine at the University of Tennessee in Knoxville.
Discuss your dog’s specific needs with your vet to see if a therapeutic diet is right for her. Here are several conditions that can be improved with a vet-prescribed therapeutic diet.
1. Your Dog Needs to Lose Weight
Many dogs who are mildly to moderately overweight may not need to change their diet. They can lose weight by increasing their level of physical activity and eating less of their current diet or switching to an over-the-counter, reduced calorie diet, says Dr. Cynthia Minter, a veterinarian at the MSPCA Angell-Animal Medical Center in Boston.
“However, dogs that struggle to lose weight with this approach or dogs that are obese may benefit from a prescription weight loss diet,” Minter says. “These diets are low calorie, high-fiber (to make your pet feel more full), and specially formulated to maintain appropriate nutrition despite being fed in very small amounts.”
They may also contain nutrients to support joint health, says Dr. Susan Jeffrey, a veterinarian at Truesdell Animal Care Hospital in Madison, Wisconsin. “Overweight pets put more stress on their joints,” she explains. These diets can also be higher in protein to help maintain lean muscle mass during weight loss, she adds.
These diets should be fed under a vet’s supervision to ensure weight loss is occurring gradually and safely.
2. Your Dog Is Prone to Bladder Stones
When minerals in your dog’s urine become concentrated and crystallize, they can form stones in the bladder or elsewhere in the urinary tract. The type of stones that develop will largely determine the diet your vet prescribes.
Some bladder stones can be prevented with a therapeutic diet, says Minter, whose professional interests include shelter medicine and preventative care. “These diets are designed to change the acidity of the urine and restrict certain nutrients to provide fewer building blocks for stone formation,” she says.
They don’t work on all types of stones, however. For example, certain therapeutic diets “are designed to dissolve struvite stones,” explains Jeffrey, whose professional interests include preventative care. Other foods or even surgery may be needed if a different type of stone is present. An appropriate diet can also help prevent the reformation of stones. “These diets help prevent the formation of certain crystals and stones by optimizing the urine pH as well as encouraging increased water intake to keep the urine diluted,” says Jeffrey.
3. Your Dog Has Kidney Disease
Chronic kidney disease is an irreversible illness that can ultimately result in death. Vets say diet modification is a critical part of your pet’s treatment.
Although a therapeutic diet won't cure kidney disease, Jeffrey says it may slow the deterioration of the kidney. “By slowing the progression of the disease, the pet lives a longer life than if it weren't on a therapeutic renal diet.”
“In fact, dogs who eat a therapeutic diet have been shown to double their lifespan, when compared to dogs eating a standard diet,” says Heinze, who is board-certified in veterinary nutrition.
Diets ideally formulated to treat kidney disease are low in phosphorous and have a moderate level of protein to help improve the clinical signs of kidney disease, Jeffrey says. “They also contain fatty acids to help modulate inflammation as well as antioxidants to help reduce cell damage.”
4. Your Dog Has a Food Allergy
Dogs with food allergies are very sensitive to the proteins found in normal diets, Jeffrey says. They may develop excessive itchiness, recurrent skin and ear infections, and gastrointestinal disease symptoms like vomiting, diarrhea, and weight loss.
“Some therapeutic diets for skin disease, such as hypoallergenic diets, contain proteins that are broken down into small pieces that are less likely to stimulate the immune system,” she says. “They also contain nutrients that help maintain the skin barrier.”
Never use an over-the-counter diet to diagnose a food allergy, Heinze warns. “They are not reliable and are frequently contaminated with other protein sources. Moreover, veterinary guidance is usually needed to do a proper food trial.”
Therapeutic diets are also available for dogs with environmental allergies or atopic dermatitis. They’re formulated to improve skin health by supplementing omega-3 fatty acids and antioxidants, Minter says. “It is important to discuss your dog’s skin issues with your veterinarian to determine whether they are due to a food allergy or environmental allergy [or something else entirely], as these require different management approaches,” she says.
5. Your Dog Has Heart Disease
Although therapeutic diets are available for dogs with heart disease, they’re not something veterinarians recommended very often. “There are some diets that are formulated to improve cardiac health by containing low levels of sodium and high levels of nutrients such as carnitine and taurine,” Minter says. However, “diet in pets with heart disease is not thought to play as much of a role as diet in human heart disease. These diets are not recommended for all types of cardiac disease. Your pet’s cardiologist will be best able to determine whether your pet would benefit from a therapeutic cardiac diet.”
While therapeutic diets don’t offer a cure, they may help slow down the heart disease process, which can help improve quality of life, Jeffrey says. “These diets contain low amounts of salt to decrease the workload on the heart. They also contain fatty acids to help modulate inflammatory reactions.”
6. Your Dog Has Gastrointestinal Issues
A dog may be put on a prescription diet for vomiting and diarrhea after the vet has determined the cause of the symptoms, Minter says. “Some pets with vomiting and diarrhea may benefit from a hydrolyzed protein diet or a novel protein diet. Others may benefit from a prescription low-residue (easily digestible) diet or a high-fiber diet.” The underlying condition determines which type of food is most likely to be beneficial.
There are many causes for chronic vomiting and diarrhea, “so it is important to discuss these symptoms with your veterinarian to help determine the appropriate therapeutic diet,” she adds.
7. Your Dog Has Seizures or Dementia
New research has emerged showing that diets formulated for neurologic health may benefit dogs with idiopathic epilepsy or dementia (canine cognitive dysfunction), Minter says. “While dogs with seizures cannot be managed with diet alone, feeding a diet formulated for neurologic health may decrease seizure frequency when used in conjunction with anti-seizure medications prescribed by your veterinarian.”
She says these diets may also help lessen the severity of symptoms of dementia and slow its progression.
Other Considerations When Feeding a Therapeutic Diet
If you’re feeding your dog a therapeutic diet, there are some important things to keep in mind. One is to avoid mixing in other foods. “The majority of therapeutic diets are meant to be the exclusive source of nutrition for maximal efficacy,” Minter says. “Many diets will only achieve their therapeutic benefit if fed exclusively. Adding human food can drastically change this formulation and reduce the efficacy of the diet.”
If you’re concerned with the taste factor, Jeffrey says palatability of therapeutic diets has improved over the years. “It's not a guarantee that every pet will like every diet, but reputable food companies will support their products and allow reimbursements if a pet doesn't like the taste,” she says. “In my experience, the diets for pets with renal disease have markedly improved in terms of taste and texture.”
If your dog refuses to eat her new diet, experts say it could be the underlying disease causing the loss of appetite, not the food. In this case, a therapeutic diet (plus medicine) can remedy it.