You should feed animal proteins to the dog and avoid proteins sourced from grain and plants. Plant-based protein causes more harm than good even to healthy dogs. If your dog is suffering from cancer, plant protein can promote the growth of cancer cells rather than restrict it. Feeding raw meat is a better option as commercial foods may not be prepared properly. Raw beef, chicken, turkey, fish, lamb, goat and pork are natural foods for dogs, and they supply the necessary proteins and fats that help in strengthening the immune system.
Some foods like sugar, for example, may actually promote development of cancer in dogs. Pets get energy from fats and proteins. The carbohydrates derived from grains provide no benefit to them. Grain is broken down into sugars, which in turn causes a multitude of problems including yeast infections, allergic dermatitis, stomach upsets and cancer. For a dog suffering from cancer, all carbohydrates should be sourced from foods that have a minimal effect on blood sugar levels.
Symptoms of some cancers, for example the symptoms of liver cancer in dogs include nausea and vomiting. Anti-cancer drugs are also known to have side effects that cause nausea and vomiting. Sometimes this leads the dog to refuse food as he associates the discomfort with eating. Although there is no evidence to prove it, a typical human trait of learned food aversion may be responsible for this. Remember the last time you fell ill after eating something. You are likely to shun that food item irrespective of any correlation between it and your illness.
The sad part is that we do not know what the dog is experiencing. The natural response of dog owners would be to coax and push food without realizing that in certain cases it may be prudent to look for alternate means of feeding or simply do nothing for a while. This is particularly important when the dog is vomiting or turning away his head at the sight or smell of specific food items.
Moreover, cancer affects the metabolic process in the body. There is also a change in the way the body uses nutrients in the food as there is a change in priorities. This is the body’s natural effort to fight the disease. If cancer is present then the body focuses more on survival rather than growth and maintenance. When these changes prolong over a long period, they actually start harming the patient and lead to systemic illnesses. The dog starts losing weight and muscle mass despite eating as before.