From the moment an animal develops cancer, the cancer begins to starve the body of the basic nutrients as it “feeds” itself and flourishes.  The cancer accomplishes this by changing the manner in which the body uses basic nutrients (including sugars, fats and proteins).  These changes result in both  an effective starvation state for the pet and a build up of poisons that result in a poor quality of life.  The end result of all changes is a less than ideal response to cancer treatment.  Recent work has shown that even if all evidence of cancer is eliminated from the body through surgery, radiation or chemotherapy, these metabolic changes remain and continue their harmful effects.  Therefore, the well being of a patient with no evidence of cancer is still in jeopardy.  These changes in our cancer patients are termed Cancer Cachexia. 

Cancer Cachexia is a complex problem that we are just now beginning to understand.  It is the most common side effect in all cancer patients and is also thought to be the most common cause of death in human cancer patients.  What is most important for you to understand is that unless we manage your pet with nutritional support, this condition will threaten the quality of your pet’s life, as well as the effectiveness of treatment.  Early in the disease process at the time that most of our patients are diagnosed with cancer, this condition can only be documented with sophisticated blood tests.  However, the condition is progressive, remains very difficult to detect clinically but always results in a patient who is effectively starving in the face of adequate nutritional intake.  In long term survivors, patients enduring cancer cachexia  eventually lose weight, become more susceptible to the side effects of treatment, and have a diminished ability to heal and fight against the cancer while traditional therapies are being given.  The exciting news is that all of these changes induced by cancer can be reversed with simple dietary changes. 

Sugars: Cancer’s energy source

Cancer requires sugar as its sole energy source.   Dramatic changes allow the cancer to meet its own energy needs using simple sugars, while making the body unable to keep up with its own energy needs.  These cancer -caused changes in carbohydrate metabolism result in increased blood levels of a body “toxin” called lactate and a hormone called insulin.  These high levels of poisons must be detoxified by the patient, thus utilizing even more of their energy reserves.  Thus the cancer patient is starving for energy and having to use its much depleted energy sources to overcome the adverse effects of the poisons produced by the cancer. 


Protein metabolism is also affected.  Cancer has been shown to decrease the body’s protein reserves and preferentially use available amino acids (the building blocks that make up protein).  This can result not only in a loss of muscle mass, but also damages important bodily functions such as immune response and healing. 

Fats: The Good News

Fat metabolism is also affected by cancer.  Cancer patients will experience changes in blood levels of the various types of fat.  Interestingly, the cancer cannot utilize any fat that is part of the animal’s diet for its own energy needs.  There is also a type of fat, n-3 fatty acids, which appears to fight against the cancer itself and prevent its spread.  Thus fat actually becomes an important tool we can use to reverse the effects of the cancer and actually fight cancer. 

Diet to Fight Cancer

The ideal cancer diet is one that is low in simple sugars (carbohydrates), relatively high in fat and should contain moderate amounts of protein.  The fat ideally should be high in n-3 fatty acids.  This “ideal” diet profile is available in a commercially prepared dog food called “n/d” which is manufactured by Hill’s.  Due to n/d’s wet formulation many dogs are unable to consume a sufficient amount of the product.  Fortunately in today’s pet food world there are a variety of grain free diets available commercially that are low in simple sugars and provide higher levels of fat and great quality protein in affordable and pallatable formulations.   The “cancer diet” is a radical change for all of our patients which essentially have been eating high sugar diets for their entire lives, thus regardless of which new diet is fed, there needs to be a gradual transition to avoid intestinal upset.