Sadly my dog was on a grain-free dog food her ENTIRE life and yet she has cancer. I've always believed that carbs fuel cancer but she eats no carbs whatsoever and I'm mostly on a Paleo diet myself.
There has been some controversy about grain-free dog food lately due to the companies substituting amino acids with plant based amino acids so I started making her dog food: chicken and veggies, but she has gotten worse.
It is actually metasizing on her skin now.

She is overweight, and she always acts like she is starving.

She does not eat a carb diet yet here we are with cancer.

According to Gerson, deficiency and toxicity causes cancer, which I believe. I do NOT believe she is eating toxic food, so how do I supplement her. She is missing something that allows the body to heal itself. For a person, you juice or fast, but how do you help a dog?