Natural, organic, whole foods are the best choice for fighting cancer, but this is not an obvious conclusion from scientific research.
Scientists can ethically gather a great deal of information about how various foods and food additives increase or decrease the risk of developing cancer. It is very rare to get scientific information about how foods and food additives help the body defeat cancer.
That is because there are so many variables in treating people who already have cancer that the benefits of an organic diet cannot be identified separately from the positive effects of medical treatment and the simple benefit of getting regular, healthy, tasty, home-cooked meals. Still, it is a reasonable assumption that natural foods are better. Here is why.
During recovery from cancer, the liver has to work overtime. The liver is not just a detoxifying organ. The liver is also a pretoxifying organ. Each one of these diets enhances some chemical pathways and inhibits others, but all in the same way that fights cancer, sometimes by freeing up liver enzymes, sometimes by using them. The liver has a limited supply of detoxification compounds, and the detoxification of chemicals in conventionally grown fruits and vegetables competes with the detoxification of drugs, hormones, and the toxins released as tumors break down.
Cancer patients often report that their liver enzymes (the enzymes assessed in blood tests to measure liver tissue destruction, ALT and AST) go up during chemotherapy but go down when they eat organic food. The detoxifying CYP450 enzymes are especially susceptible to nitrates in food, either from lettuce and other salad greens grown with a heavy dose of chemical fertilizer, or to similar compounds in cured meats and the "char" on grilled steaks and burgers and barbecue. The dizzying array of other food additives and contaminants are not good for anyone, but none have the impact of the nitrates for people seeking to recover from cancer.
The meals that heal cancer are high in potassium and magnesium and low in salt. Antioxidant content is helpful, but you need vastly less antioxidants from food sources than from supplements for the same benefit to your health. Simply make sure you avoid salty foods and eat nine servings of fruits and/or vegetables every day, and you have accomplished the most important step in making your diet an important part of your cancer cure.