By Keith I. Block, MD
Virtually every day, we’re all bombarded with advice about our diets. We’re told which foods to eat to have more energy, reduce our cholesterol, lower our chances of a heart attack, reduce our risk of getting cancer … yet once someone is diagnosed with cancer, these recommendations often fall by the wayside. Though defying both common sense and good science, some cancer patients are still hearing “eat whatever you want, you need to keep up your strength,” by their physicians. And, this holds true even when their dietary choices are loaded with saturated fats and refined sugars!
At the Block Center for Integrative Cancer Treatment , we believe diet always matters. Whether someone is looking to prevent cancer, undergoing treatment, or wanting to reduce the risk of a recurrence, eating a nutritionally-dense, healthy diet is important. Nutrients directly and indirectly impact the mechanisms by which cancer cells grow and spread. For example, if you eat too much dietary fat and refined carbohydrates, you run the risk of increasing your body fat and weight, while weakening your immune system and increasing inflammation, oxidative stress and blood levels of substances that promote tumor growth and angiogenesis (new blood supply to tumors). In addition, diets high in fat tend to cause more DNA damage, which allows mutations to accumulate in the cells that make up tumors. The more mutations, the more aggressive the cancer, and the more likely it is that malignant cells will survive chemo and radiation, and then metastasize. Nutrients indirectly help control the cancer by changing the surrounding biochemical conditions that either encourage or discourage the progression of malignant disease.
Our Dietary Recommendations
Whether you’re undergoing treatment, or wanting to prevent a recurrence of cancer, our general dietary recommendations are the same: we suggest a diet low in saturated fat, high in fiber, plant-based sources of protein, cold water fish rich in omega-3 fatty acids, complex carbohydrates, fruits and berries rich in antioxidants, and nuts, seeds and cruciferous vegetables. The inclusion of whole grains and legumes is consistent with the basic eating pattern for many traditional societies in which the major cancers that afflict the US are practically non-existent. One of the many benefits of eating whole grains and legumes is their fiber content. Soluble and insoluble whole grain fibers are, among other things, excellent for the health of the intestines. Cells lining the colon, for instance, need fiber and carbohydrates for some of their basic nutrients, such as butyrate. And with the negative effect of many cancer treatments on the gastrointestinal tract, these cells need all the support they can get! The soluble fiber of whole grains and beans also evens out fluctuations in insulin levels – and since our diet recommends the exclusion of refined sugar and flour sources (more on this below) – insulin spikes should be less problematic to begin with. High fiber diets have also been shown to lower inflammation – important because inflammation can promote the growth of cancer.
Additionally, we suggest eliminating unnatural fats, called trans fat, found abundantly in margarine, hydrogenated oils, as well as many baked goods and convenience foods; reducing or eliminating simple carbohydrates such as sugar, honey, high fructose corn syrup, concentrated sweeteners, sugary beverages, cookies, cakes, pastries, white bread, crackers and white-flour baked goods. These are high-glycemic foods that cause a sudden rise in blood sugar and, ultimately, increase inflammation.
Our nutritional strategy is intended to help curtail inflammation, reduce free-radical damage, minimize platelet activation (which can lead to dangerous blood clotting), manage blood sugar surges, and reduce serum levels of insulin-like growth factor 1 (or IGF-1), which stimulates cell multiplication and inhibits cell death.