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5 Possible Causes Of Cancer In Dogs And Cats

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5 Possible Causes Of Cancer In Dogs And Cats

Things To Avoid If At All Possible
Dr. Dennis Thomas
Dr. Dennis Thomas More by this author
Nov 29, 2016 at 12:15 PM

Statistics tell us that about 6 million dogs and 6 million cats will be diagnosed with cancer this year.  One in two dogs will be diagnosed with cancer and one in four will die from cancer. 

When most veterinarians are asked why the alarmingly high number of pets are getting cancer, the answer is usually that pets are living longer and cancer is usually a senior pet disease.  This is partially correct, but certainly does not tell the whole story.

As a holistic veterinarian, I see a large number of pets with cancer in my office.  Every day I see at least one dog or cat that has been diagnosed with a malignant cancer and the caretaker has been told that the disease will eventually kill their pet. 

The reason that most people are seeking the advice from holistic veterinarians about treating their pet that has been diagnosed with cancer is that the traditional western-medicine approach to treating cancer is usually minimally effective, has potentially harmful side effects and can be very expensive. 

Most caretakers are given the option for chemotherapy or to focus on keeping the pet comfortable until the diseases has taken its toll.

For more in-depth examination of holistic versus conventional pet health treatment please see my book, Whole-Pet Healing.

5 Causes of Cancer


We humans are capable of sending a rocket ship to the moon and returning without a problem, produce computers that function like a human, but still can’t find the cause of cancer, nor the cure for it.

Most cancers found in pets are not caused by a single source.  There are a few cancers that can be directly linked to one source, such as over-exposure to ultraviolet radiation causing skin cancer and feline leukemia-causing cancer in cats, but the cause for the most common forms of cancer in the dog and cat are still unknown.  The reason that the cause is difficult to determine is that the cause is usually a long-term accumulation of many variables.    

Unfortunately, in the dog and cat, this usually starts at a very early age and continues to make subtle changes in the body until the cancer shows its ugly self in the final stage.  In my experience as a holistic veterinarian, I see two common factors in most of my cancer patients. 

  1. Inflammation
  2. Poor immune function. 

Chronic inflammation and poor immune system function can be deadly precursors in the evolution of cancer.

In dogs and cats, it is accepted that inflammatory bowel disease can be a precursor for intestinal cancer.  This is why bowel biopsies are so important for correct diagnosis.  The surgical biopsies will indicate if the bowel disease is still inflammatory in nature or if it has regressed into the cancer state.  This obviously will help the clinician determine treatment options as well as prognosis for the pet.

If chronic inflammation and immune imbalance are primary factors for the formation of cancer, where is the source of the problem? 

  1. The most likely factor is the diet that we feed our pet. 

Research has indicated that feeding heat-processed pet food has been linked to chronic inflammation.  Heat-processed kibble not only stimulates the production of inflammatory cytokines (chemicals) that circulate in the body around the clock but also contains starchy carbohydrates. 

Starch, when fed to carnivores (dogs and cats) is converted to sugar and just like in people, sugar causes inflammation in the body. 

 As a responsible pet caretaker you want to do what is right for the pet and you go to buy the best pet food available.  You pick out a brand that you recognize and you read the label and it appears that the ingredients are wholesome and high quality.  Unfortunately, this is not the whole story. 

All of those wonderful ingredients were radically changed during the heat-processing.  The nutritional value has been reduced so much from the processing, that the food now has to be fortified with chemical supplements in order to meet government requirements. 

Preservatives and other chemicals are added for increased shelf life, bags are lined with chemicals that leach into the food and by the time the food is consumed by the pet there are high levels of mycotoxins and other contaminants.

Many puppies and kittens that are fed these diets develop a low-grade inflammatory process in the intestinal wall.  When the gut gets inflamed it becomes more permeable and allows improperly digested food particles to enter the body.  This is often referred to as Leaky-gut syndrome. 

As the improperly digested food enters the body, the immune system identifies the food particles as a foreign invader and will often amount an immune response.  In time the over-active immune system becomes imbalanced and diseases such as allergies begin to show up in the pet.

A healthy immune system requires a healthy gut.  As time goes by, the same combination of chronic inflammation and poor immune health creates other diseases such as organ imbalance, heart disease, immune-mediated disease and arthritis.  If the pet lives long enough, cancer is likely to occur.

There are many other causes of inflammation and immune imbalance in the pet, but none as significant as poor diet.  In my opinion, if you want to feed your pet a diet in hopes of preventing cancer, then feed a balanced diet using wholesome, non-processed food.  I also recommend giving a digestive enzyme supplement to all dog and cats in order to help increase the efficiency of digestion.

It is widely accepted in the medical field that poor gut function means poor immune function.  But, there are many other factors that affect the immune system besides poor diet. 

  1. One problem that research suggests may likely be a factor is over-vaccinating our pets. 

Vaccines are manufactured in order to expose the body to modified viruses to prompt a protective immune response that would likely protect the pet from a similar virus in the environment.  This is fine but we need to understand that unnecessary stimulation of the immune system can be harmful. 

We should not allow undiscriminating vaccination for vaccines that are not needed.  Instead of boosting vaccines during adulthood, we should be testing them for protective status by doing antibody tests for those viruses.  This will keep us informed of our pet’s protective status without over-stimulating their immune system by unnecessary vaccination.        

  1. There are many environmental factors that can contribute to the formation of cancer in the pet’s body. 

Recent research indicates that the leading cause of gut cancer in the cat is second-hand cigarette smoke.  The chemicals from the cigarette smoke get onto the cat’s hair coat and when the cat grooms itself, it ingests the chemicals, initiating an inflammatory response in the gut which can predispose cancer.  My advice is to avoid any long-term exposure to harsh chemicals including pesticides that are placed on the pet for flea and tick control.          

    4.  Electric smog is a catchy phrase that is being used for those potentially harmful subtle energies that are in you and your pet’s environment that can potentially be harmful to the body. 

More accurately known as electromagnetic radiation, these subtle energies can be emitted from many energetic sources in the environment ranging from the energy emitted from microwaves to the energy emitted from the power lines.  We know that some energetic waveforms such as ultraviolet radiation and x-rays have been directly linked to cancer, but other sources such as cell phone and computers are still being studied.  The point is, try to avoid exposure to these potentially harmful sources of unhealthy energy.

  1. The other energetic source that can be a contributing factor for pets developing cancer is stressful energy in the home environment. 

Research has shown that stress over time leads to poor health for the physical body.  The same is true for the pet.  Subtle energy, given the laws of quantum physics, will seek a harmony called entrainment.  If there is persistent negative stress in the environment, the unhealthy energy from those negative emotions will interact with the energetic body of the pet and in time cause physical disease. 

There are many remedies for treating pets with cancer.  They might include pharmaceuticals, herbs, supplements, alternative modalities such as acupuncture, homeopathy, healing touch, Reiki and many more.  Next month I will be writing another article here which will describe 8 different ways to treat cancer in your pet. Stay Tuned... 

For more in-depth examination of holistic versus conventional pet health treatment please see my book, Whole-Pet Healing.

About Author
Dr. Dennis Thomas
Dr. Dennis Thomas has been a veterinarian for more than 30 years. After two decades of practicing Western allopathic veterinary medicine, he learned Traditional Chinese Veterinary Medicine Continue reading