Dog Cancer Diet: What to Feed a Dog With Cancer

By: Nancy DunhamUpdated:

dog cancer diet: small dog sniffing food in bowl Blanco

Dog Cancer Diet: What to Feed a Dog With Cancer

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When a dog has cancer, their diet can play a significant role in their quality and length of life. But for pet parents, knowing the right foods to offer is often confusing.

Dogs with cancer go through complex biologic changes that require a delicate nutritional balance. While there are some basic guidelines you can follow, dog parents should partner with their veterinarian or other canine health care specialist to determine the best dog food for cancer patients.

How Does Cancer Affect a Dog’s Digestive Process?

Cancer has the ability to disrupt much of a dog’s digestive process. The disease and its various methods of treatment can cause a lack of saliva and growth of mouth ulcers. Nausea, vomiting, diarrhea and loss of appetite are also side effects. In other words, a dog’s quality of life can be greatly diminished.

Some parents of dogs with cancer are so anxious to comfort and show love to their furry friend they overfeed their pet. Others feed their pup unhealthy commercial or home-cooked meals, says Adam Christman, DVM, MBA, chief veterinary officer for dvm360. Both are blunders that could make the dog ill or even promote cancer growth, Dr. Christman says.

That's why it's vital to consult with a veterinarian, oncologist or animal nutrition specialist to ensure you feed your dog the proper diet.

Why Diet Is Important When Your Dog Has Cancer

To understand why diet is so important for dogs with cancer, pet parents should know that cancer is primarily fed through oxygen and carbohydrates, says Dr. Carol Osborne, DVM, of Chagrin Falls Veterinary Center & Pet Clinic in Chagrin Falls, Ohio. And while we can’t adjust the oxygen, we can adjust the carbs, she says.

“We prescribe diets in which we try to maintain the animal’s body weight and body condition as we try to starve the cancer,” Dr. Osborne explains.

Studies indicate that cancer cells have a difficult time using fat for energy, but they feast on carbohydrates, says Dr. Osborne, who has conducted research on cancer in animals. She adds that higher levels of omega-3 fatty acids may actually help reduce tumors.

Dog Cancer Diet: What to Feed a Dog With Cancer

The ideal dog cancer diet is as unique as each dog themselves. But there are general guidelines many vets follow.

  1. Avoid making drastic changes to your dog’s diet until you’ve consulted a veterinarian, oncologist or another specialist. A primary goal of feeding a dog with cancer is ensuring they maintain their body weight, says Dr. Sara Ochoa, DVM, a veterinarian at Animal Hospital of West Monroe in West Monroe, Louisiana and the co-founder of How To Pets. That’s why it’s important for pet parents consult a vet before making any changes to their dog’s diet.
  2. Avoid switching up your dog’s food often. This is a major mistake owners make, Dr. Ochoa says, and it can lead to diarrhea and vomiting. "This is not something we like to see with our cancer patients," she says.
  3. You can gradually mix and match foods. It’s may be wise to slowly mix and match foods to give dogs a variety in taste, especially if dogs are undergoing chemotherapy. Dr. Ochoa recommends gradually feeding dogs different flavors of the same brand of food to avoid causing stomach upset. “Similar to humans, their taste buds are different, and hence providing a healthy array of foods without causing a food aversion is an important understanding,” she says. “You shouldn’t put your dog on a [limited] diet unless enforced by the veterinarians.”

Best Dog Foods for Cancer

For dogs diagnosed with cancer and without other dietary or health concerns, Dr. Osborne recommends a diet full of easy-to-digest fatty high-quality proteins, like chicken, turkey, pork, fish and eggs. Different cuts of meat or fish have varying amounts of fat, so read labels when you look for these ingredients in store-bought dog foods or prepare homemade dishes with those ingredients.

Store-bought dog food


You can find high quality protein in store-bought dog foods such as Hill's Prescription Diet ONC Care Dry Dog Food. "Specially formulated to support dogs fighting cancer," Hill's dry kibble dog food features flavorful fats and highly digestible protein to help maintain muscle mass, strength and energy; a formula that supports your dog's gut bacteria for a healthy GI microbiome balance; added essential omega-3 fatty acids that provide immune system support; and a unique blend of prebiotics that provide consistent stool quality.

Before switching your dog's food, though, check in with your veterinarian, who can assist you in finding the best store-bought choice for your dog.

Homemade meals for dogs

dog eating out of dog bowl
Photo: Vyshnova

Pet parents who cook their own meals for their dog should ensure poultry, pork, fish and organ meats such as liver are thoroughly cooked to kill microbes both inside and on the surface of the meat, Dr. Christman says.

Also, remember that you want your dog to maintain their weight.

“You are not looking for lean cuts. You are looking for cuts with fat,” Dr. Osborne says. “When it comes to vegetables, look for cruciferous ones. Certain cruciferous vegetables, including cauliflower and turnips, have cancer-fighting properties.”

Before feeding your pet a homemade diet, however, seek advice from a board certified veterinary nutritional specialist, who can ensure the diet is balanced and individually tailored for your pet.

Learn more about homemade pet food for dogs with cancer.

Supplements to Give a Dog with Cancer

Supplements may help ensure your dog with cancer has a balanced diet, especially if the parent is cooking the food, Dr. Ochoa says.

Dr. Christman recommends probiotics, vitamin B complex, amino acids, iron and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are two of several omega-3 fatty acids.

  • Probiotics: Probiotics help support and strengthen the immune system. Probiotics boost the amount of good bacteria that competes with the harmful bacteria for nutrients and intestinal binding sites. This helps the immune system fight off disease.
  • Vitamin B complex: B vitamins are essential for the immune system and digestive tract function.
  • Amino acids: Amino acids are the basic building blocks of proteins, which form muscle and other body tissues.
  • Iron: “Iron is a key component of hemoglobin, which binds to and transports oxygen around the body,” says Dr. Christman. “Cancer and chemotherapy can contribute to anemia, so giving an iron supplement to cancer patients can help combat anemia.”
  • EPA and DHA: EPA and DHA not only decreases muscle and weight loss in cancer patients, per PetMD, but these two omega-3 fatty acids also modify the inflammatory response of the immune system to cancer activity, reducing tissue damage by decreasing certain inflammatory molecules. “With cancer, there can be a muscle-wasting effect that leads to weight loss and overall weakness,” Dr. Christman says. Severe loss of both muscle and fat is a condition called cancer cachexia.

What about CBD? "People have been reaching for CBD oils to help with appetite and cancer,” Dr. Ochoa says. “CBD should be discussed with your veterinarian to make sure it will not interact with any other treatment they are receiving. At this time, we have limited research done on the effects of CBD in cancer patients.”

Speak with your vet before giving your dog supplements, speak with your vet, who can recommend the right supplements for your pet.

Superfoods for Your Dog

Veterinarians all have different go-to human foods they recommend for their patients. Organic (since no pesticides is a good way to go) and high-protein and cruciferous foods, as well as berries, are often high on their lists for their cancer-fighting properties.

Some of the most popular superfoods for dogs include:

  • Broccoli
  • Chicken
  • Fish
  • Organ Meat
  • Eggs
  • Strawberries

When feeding your dog human foods, remember that these treats should only constitute a small percentage of your pet’s daily food, less than 10 percent. Consult your pet’s veterinarian before offering these food items.

What to Do If Your Dog Begins to Lose Their Appetite

Another point to consider is that dogs react to smell. If your dog begins to lose their appetite, lightly season their food with dog-safe spices, like coriander, turmeric and ginger, just as you would your own food, Dr. Osborne says.

Foods to Avoid

Again, no one diet suits all dogs with cancer. Vets’ dietary decisions are based on a dog's history, other diseases the pet might have, and the stage and type of cancer.

However, it’s sometimes suggested to go grain-free or choose food that have oats or other whole grains.

“The most dramatic metabolic disturbance occurs in carbohydrate metabolism,” Dr. Christman says. “Cancer cells metabolize glucose from carbohydrates through a process called anaerobic glycolysis, which forms lactate as a byproduct. The dog’s body must then expend energy to convert that lactate into a usable form. The end result? The tumor gains energy from carbohydrates, while the dog suffers a dramatic energy loss.”

Many commercial dog foods have grains because they are inexpensive fillers. If you must buy one to feed your dog with cancer, make sure that the first ingredient on the label is protein and any grains are either whole grains or at the end of the list.

But vets caution that not all dogs with cancer respond well to high-protein diets. In fact, Dr. Christman warns a high-protein diet may have negative results for some dogs, specifically those who have both cancer and other medical concerns, such as kidney failure.

Again, pet parents should consult with their specialists to determine if a high-protein diet is right for their dog.

Receiving a diagnosis for your dog can be one of the scariest things you go through as a pet parent. A proper diet, with input from your vet or other pet care specialist, is one weapon in your arsenal that can help in your battle. Don’t expect a diet to produce miracles, though. It’s only one part—albeit an important part—of your dog’s cancer treatment plan.

Learn more about cancer in dogs, including the tools and products that can help improve your pet's quality of life.


By: Nancy DunhamUpdated: