The seven dietary suggestions of the American Cancer Society (ACS) are very similar:

1. Avoid obesity.
2. Cut down on total fat intake.
3. Eat more high-fiber foods, including whole grains, fruits, and vegetables.
4. Include cruciferous vegetables, such as cauliflower, broccoli, and cabbage.
5. Include foods rich in vitamins A and C.
6. Lower alcohol consumption.
7. Lower intake of salt-cured, smoked, or nitrite-containing foods.

So we begin with a high-nutrient, low-fat, high-fiber diet. More specifically, protein intake should be about 15 percent of the diet—from 12–18 percent, and not more than 20 percent, or 100 grams (400 calories) per day. Complex carbohydrates could make up about 60 percent of the diet, which would greatly increase the fiber intake. Up to 40 grams daily of fiber is not unrealistic. Foods high in fiber and water content to promote good bowel function and a diet and lifestyle supportive of healthy adrenal glands (minimize stress and sugar), liver (minimize chemicals and alcohol), thyroid (less stress and radiation exposure), and thymus/immune system (see Immune Enhancement program to review immune suppressors and supporters) are all important in keeping cancer risks low. In addition to vitamins A and C, we want to increase dietary intake of the B vitamins, especially folic acid, vitamin E, selenium, beta-carotene, and zinc. The diet should be low in alcohol, salt, coffee, and, obviously, chemicals and preservatives in foods.

Our low-fat, cancer-prevention diet focuses on starches, such as whole grains, legumes, potatoes, pastas, and squashes, along with fruits and vegetables and some other protein foods, such as small amounts of meats, preferably fish and poultry, nuts and seeds, and occasional eggs or milk products if tolerated. The overall best foods for cancer prevention include organic white meats of poultry and fish, whole grains, vegetables, especially organically grown cruciferous ones, and fruits, such as citrus fruits. The worst are high-fat, chemical foods and smoked, barbecued, or pickled foods.

A primarily or exclusively vegetarian diet is generally helpful in preventing cancer. All studies of people on vegetarian diets showed reduced incidences of a variety of cancers, including the common ones of the colon, breast, and prostate. The macrobiotic (primarily cooked grains and vegetables) and vegan diets (avoiding eggs and milk) probably pose even a lower risk than the classically researched Seventh-Day Adventist diet; although both these diets contain wholesome foods, they must be watched for deficiency problems. A macrobiotic diet has become popular among people who are suffering from cancer or concerned about preventing it. Such a diet focuses on whole grains (50–60 percent); vegetables (25–30 percent), mainly cooked; soups (5–10 percent); and beans and sea vegetables (5–10 percent). Michio Kushi discusses the macrobiotic diet and its application to cancer in great detail in his book, The Cancer Prevention Diet. Also refer to Chapter 9, Diets, in this book.

Certain vegetables from the cruciferous family have recently been recognized as having anticancer properties. These include broccoli, brussels sprouts, cabbage, kale, bok choy, and cauliflower. They increase the levels of the enzyme aryl hydroxylase in the liver, lung, and intestines; this enzyme detoxifies many carcinogens and blocks their action. It may be the indoles and isothiocyanates in these foods that activate the enzymes. Other foods that may increase the action of aryl hydroxylase include spinach, lettuce, mustard greens, kohlrabi, turnips, and parsnips. Chlorophyllic greens and wheatgrass also may have a positive anticancer effect through their purification and detoxification functions.

Since I consider the genesis of cancer largely a result of autointoxication, chemical exposure, stagnation, and congestion (physical, mental, and emotional), I believe that periodic detoxification diets and fasting are appropriate for most people as a preventive to degenerative disease and to generally improve clarity and vitality. Juice fasting or a fruit and vegetable detoxification diet also helps us reflect on and reevaluate our diets, attitudes, life priorities, and personal path. This enhances our evolutionary process which I feel is essential to "staying healthy." For more information on Fasting and Detoxification, see Chapter 18.

The Ideal Diet, as discussed in Part Three, is basically a good anticancer diet as well. It is a moderately low-fat, low-calorie, high-fiber diet that includes many of the nutrient-rich foods, such as fruits, vegetables, whole grains, legumes, seeds, nuts, and the low-fat animal proteins if desired. It is adapted to the seasons, which allows better availability of organically grown local produce, extremely important in minimizing intake of potentially dangerous chemical carcinogens.

I was very impressed with a recent publication by the American Institute for Cancer Research entitled An Ounce of Prevention. It is a four-volume series, one volume for each season, presenting a low-fat, high-fiber, chemically light, healthy-looking diet with a focus on practical recipes. It was very pleasing to my heart to see each volume devoted to a particular season, with colors and all, containing recipes rich in the naturally grown foods. This is the concept that I have been advocating for over a decade. The new seasonal back-to-nature diet approach is catching on again and leading the way back to greater nutritional health and vitality.

Let us now explore some of the anticancer nutrients. There are three main avenues for defense against cancer, and each has specific nutrients that will support that function:

1. Strengthening the immune system—vitamins C and E, vitamin A and beta-carotene, zinc and copper, and the B vitamins folic acid, riboflavin, pyridoxine, and pantothenic acid.
2. Avoiding or neutralizing carcinogens—vitamins C and A, selenomethionine, and the amino acid L-cysteine.
3. Preventing DNA and cellular damage—vitamin A, vitamins C and E, beta-carotene, and the minerals selenium, zinc, and manganese.

The diet I have suggested will provide adequate levels of most of these nutrients if the foods are digested and assimilated. High amounts of fruits and vegetables will provide lots of vitamins C and A, beta-carotene, and some of the B vitamins. Whole grains will give us more B vitamins, some vitamin E and most minerals. Good-quality proteins will provide amino acids and cysteine. With a more vegetarian and low-fat diet there can be slight deficiencies, such as vitamin E, and, depending in some cases on the soil content, zinc and selenium, both of which may require supplementation.

Vitamin A and beta-carotene are also important anticancer nutrients that support normal cellular differentiation of the tissues and internal linings. Vitamin A may prevent cancer cell formation by inhibiting the binding of carcinogens to the cell wall; similarly, beta-carotene may protect the DNA in the nucleus of the cell by decreasing the bonding of chemicals to the membrane around the nucleus, which contains the DNA, our basic life material. Both of these nutrients are antioxidants that scavenge free radicals, particularly singlet oxygen molecules. Decreased levels of vitamin A are associated with increased rates of cancer of the lungs especially, and also of the mouth, esophagus, bladder, cervix, and stomach. Beta-carotene has been shown to be deficient in a large proportion of smokers who develop lung cancer, as it seems to specifically protect cells of the mucous membranes. It has also been shown to be low in people who develop cancers of the throat, skin, prostate, and colon and is probably protective against those cancers as well. Due to its stronger antioxidant functions, beta-carotene is likely the better anticancer nutrient than the retinol form of vitamin A. Zinc, which is needed to form the retinol-binding protein (for vitamin A), may also be low in people who develop cancer. Vitamin A and especially beta-carotene are found mainly in fruits and vegetables, such as carrots, sweet potatoes, squashes, greens such as spinach and broccoli, seaweed and blue-green algae, bell peppers, apricots, and cantaloupe. Vitamin A in the retinol, or animal, form is found in fish, eggs and liver.

Vitamin C is involved in all three of the cancer defense functions and is obviously an important nutrient. It is one of the main antioxidant nutrients, protecting cell and mucous membranes and vascular linings from free radicals generated by carcinogens and other molecules. Even though the use of ascorbic acid in cancer treatment is controversial, it is important to use for cancer prevention. This vitamin is abundant in foods such as citrus fruits, cruciferous vegetables, and peppers. With the current stresses and chemical exposures in our society, and the inability to acquire high levels of vitamin C from our diet, I usually suggest some regular supplementation, at least 2–3 grams daily, though even 500–1000 mg. (0.5–1.0 gram) is probably sufficient for most of its protective functions. Rutin, one of the vitamin C-complex nutrients, or bioflavonoids, found in various foods and herbs, may also have some anticancer properties.

Anti-Cancer Aspects of Vitamin C

1. Is an antioxidant.
2. Stimulates T lymphocytes to produce interferon, which decreases virus reproduction.
3. Supports thymus function, specifically in strengthening the cytotoxic and killer T lymphocytes, and supports antibody responsiveness.
4. Reduces the production of nitrosamines (a strong carcinogen) from dietary nitrates and nitrites from the soil and those added to smoked or processed meats, and those we produce through our own digestion and metabolism.
5. Reduces stomach, esophageal, and bladder cancers by means of its multiple protective effects on mucous membranes (this needs more research).
6. Has been shown, along with folic acid, to minimize cervical dysplasia and cancer, where these nutrients have been measured at reduced levels.