Last Updated on November 7, 2022 by
Oh boy. Do I have a post for you today! Turns out pet food that is marketed as “natural” or “holistic” caused my dog to develop lymphoma and leukemia. At least, that’s what I’ve determined after a year-long investigation. In this post, I’m going to share the details of my findings, as well as the shocking discovery of another popular brand of pet food. The facts about these brands are simply astonishing — yet nothing is being done about it.
When you first realize that pet food can cause cancer, it’s natural to be scared and confused. But overwhelming emotions can hold back important decisions when it comes to your dog. So here are 7 things you must know about cancer and pet food.
Dog owners are told to feed their pets cheap pet food and yet there are many brands of dog food that contain dangerous ingredients that can cause cancer.
Pet Food That Causes Cancer

We wish we could provide you with a list of all the dog food brands to avoid. Sadly, it’s simply not possible. No scientific research has revealed that any one kind of dog food is linked to cancer in dogs. Even the claims that kibble can cause issues aren’t so cut and dry; there are plenty of high quality kibble brands without a high risk of cancer.
But, while it can be impossible to paint the canine food industry with broad strokes, it is a good idea to be on the lookout for specific ingredients. Indeed, there are a few select food sources that have been linked to cancer in humans, rats, and sometimes dogs. So, exploring those ingredients can help answer which dog foods cause cancer.
Which ingredients have been linked to cancer?
The ingredients on this list have correlated to cancer in certain animals. That doesn’t mean that they will certainly cause cancer; rather, that concerned Dog Owners might want to avoid them to be safe:
Foods that cause inflammation. In a review of the scientific literature on inflammation and mammary cancer in humans and dogs, researchers found evidence that inflammation can increase the risk for cancer and accelerate its growth. As such, Owners should stick with fresh ingredients and a diet rich in Omega-3 fatty acids, which have inflammation-busting effects.
Meat cooked at high temperatures with dry heat. One of the most important recent discoveries in nutrition science was the finding that foods, especially meats, cooked at high temperatures could release carcinogens. Unfortunately, dog food companies have an incentive to process their meat as quickly as possible. This can lead some dog food providers to depend on this dangerous cooking method. Frustratingly, it can be hard to know which dog food brands rely on this form of meat processing. However, some high-end dog food companies claim to cook their dog food at lower temperatures.
Ingredients infected by aflatoxins. Carcinogenic aflatoxins are produced by a type of fungi common in agricultural products, such as corn, wheat, and sometimes milk and other dairy products. Unfortunately, prevention of aflatoxins falls to food manufacturers, so consumers should stick with reputable brands and discard any food that is mouldy.
Pesticides. Another cost-cutting measure that many dog food producers rely on is the use of pesticides, which pose an increased risk of cancer. Dog Owners can lower their pup’s exposure to pesticides by opting for organic dog foods.
Now, how about the question of preservatives? In our recent article, Kibble vs Canned Food, we mentioned that preservatives can pose a health risk for dogs. But should we also worry about links to cancer? According to the existing scientific literature, there isn’t enough evidence to link preservatives in dog food to cancer.
Can weight gain cause cancer in dogs?
Another way to think about the question, “Which dog foods cause cancer?” is more about overall health than specific ingredients.
Excessive weight and obesity are generally risk factors for a dog’s health. And, they may also increase a risk for certain types of cancer, such as in the case of mammary gland tumors.
We should note that there’s a lot to be desired when it comes to research on obesity and cancer in dogs. One study, for example, found there was no correlation between cancer and weight, but the sample size was small enough to discredit the results. Hopefully, future research will strengthen the data on the topic.
That said, obesity has been linked to inflammation, one of the risk factors that we’ve mentioned for cancer. And because excessive weight gain relates to so many other health concerns, from respiratory disease to diabetes and osteoarthritis, it’s still a good idea for Dog Owners to avoid unhealthy dog and people food.
Clearly, the answer to “which dog foods cause cancer in dogs?” is confusing. What is a responsible Dog Owner to do?
We certainly don’t want to send you away with more questions than answers, and luckily, there are a few things that you can look out for when choosing a dog food. Stick with these standards, and you can be sure that your pup is getting the healthiest food possible:
Fresh preservative-free ingredients. The fresher your dog’s food, the less you have to worry about mould, harmful preservatives, and over processing.
Human-grade. While dog food nutrition has improved by leaps and bounds over the last few years, the fact is, human-grade food continues to be more strictly regulated. If you want Fido to eat the best, look for human-grade dog food.
Balanced nutrients. Natural antioxidants, in the form of fresh broccoli, squash, sweet potatoes and spinach, can help your dog’s system deal with carcinogenic free radicals in the body.
Raw. Sticking with raw and fresh dog food is an effective way to keep your pup from eating ingredients that have been affected by high heat cooking.
Last tips to give your pupper a healthy life
In addition to a raw, fresh, balanced diet, you can give your pupper the best chance at avoiding a cancer diagnosis with a healthy lifestyle. Regular exercise, vet screenings, and a stress-free life can make a huge difference in your dog’s overall health.
And, if you have more questions similar to “Which dog foods cause cancer?” stay up to date with the latest health articles on the Mad Paws Blog!