Cancer Prevention and Diet

by John G. Connor, M.Ac., L.Ac. edited by Barbara Connor, M.Ac., L.Ac.

TABLE OF CONTENTS
Introduction
Useful Vegetables
Useful Fruit
Useful Grains, Legumes and Other Foods
Herbal and Nutritional Support
Foods to Avoid
References

INTRODUCTION
According to the American Cancer Society over one million people get cancer each year. Approximately one out of every two American men and one out of every three American women will have some type of cancer at some point during their life time.  Anyone can get cancer at any age; however; about 77% of all cancers are diagnosed in people aged 55 and older.  Since this article focuses only on cancer prevention through diet we need to emphasize the importance of  including lifestyle risk reductions in your cancer prevention program as well. We hope the information contained in this article helps you in your quest for maintaining a healthy cancer-free life.

USEFUL VEGETABLES
• Asparagus- has a cleansing effect on the lymphatic system and kidneys. It contains protein compounds called histones which are believed to act as cell-growth normalizers on cancer-cell division.

• Avocados- are perhaps the best overall source of essential fatty adds and glutathione and are a great source of protein. Avocados are easily digested, making them an ideal food for people recovering from surgery or for the very sick

.• Beets and radishes – support the liver and have anticancer properties. According to Alexander Ferenczi, MD of Csoma, Hungary beetroot contains a tumor-inhibiting substance attributed to its natural red coloring agent, betaine.

• Bitter melon. The fruit and leaves of bitter melon are a source of a guanylate cyclase inhibitor which has been shown to inhibit prostate cancer.

• Broccoli, cauliflower, Brussels sprouts, apples, grapefruit, apricots and cherries – contain D-glucarate. a natural compound produced in small amounts by humans and some plants. It encourages the detoxification of environmental carcinogens and estrogenic tumor promoters.

• Broccoli, Brussels sprouts, kale, cauliflower, carrots and green onions  contain a potent anticancer compound called sulphoraphane which according to scientists at John Hopkins medical school greatly increases anti-cancer enzyme systems in cells. They also contain isothiocyanates which enhance glutathion S-transferase, which helps in carcinogen excretion. Broccoli sprouts contain up to 100 times more sulforaphane than does broccoli itself. Another compound found in broccoli and other cruciferous vegetables called indole-3-carbinol has been shown to increase the excretion of a form of estrogen called 2 hydroxyestrone, which is linked to breast cancer.

 • What are the advantages of eating cruciferous vegetables?  “Cabbage family vegetables include cabbage, broccoli, cauliflower and kale.  These flavorful foods, also called cruciferous vegetables, contain anti-cancer phytochemicals known as glucosinolates.  The most important of these is indole-3-carbinol (I3C).  Studies have shown that increasing the intake of cabbage family vegetables or taking indole-3-carbinol as a dietary supplement significantly increase the conversion of estrogen from cancer-producing forms to nontoxic breakdown products.  Thus I3C is thought to be especially protective against breast and cervical cancers.”  (How to Prevent and Treat Cancer with Natural Medicine p. 85)

• Broccoli and onions – contain quercetin. a flavone which has a cancer inhibiting effect by preventing a defect in the tumor suppressor gene p53. Quercetin also inhibits the tumor producing PGE-2 series by blocking proflammatory reactions in the body.

• Broccoli contains dithiolethiones which trigger the formation of glutathione S transferase, which may prevent carcinogens from damaging a cell’s DNA.

• Carrots, sweet potatoes, collard greens, cantaloupe, squash, apricots, fresh pumpkin, kale, spinach, mangos, papayas and yams – contain beta-carotene which is considered one of the most promising anti-cancer agents. In one study the more beta-carotene men got in their diet the less lung cancer they developed. It may also prevent a second tumor in patients who have been cured of an initial cancer but now stand at an increased risk of developing new cancers in the upper part of the digestive tract. Carotenoids are best assimilated if taken with a fat such as flaxseed oil or olive oil.

 • Celery – contains abundant amounts of phthalides and polyacetanes two phytochemicals that have been shown to inhibit cancer. They are able to detoxify many carcinogens and are of particular help in reversing some of the damage done by cigarette smoking.

• Chili peppers – contain capsaicin which may neutralize the carcinogenic effect of nitrosamines, which are powerful carcinogens that can form in the stomach. Capsaicin may also block carcinogens in cigarette smoke from locking onto DNA -possibly preventing genetic damage that can lead to lung and other cancers.

• Dandelion root – has been shown to have antitumor effects in mammary carcinoma in mice, due to cytolytic activation of macrophages.• Dark green leafy vegetables, cold pressed vegetable oils, legumes, nuts, seeds, whole grains, brown rice, eggs, kelp, desiccated liver, milk, oatmeal, soybeans, sweet potatoes, watercress, wheat, wheat germ, flaxseed and dong quai – contain vitamin E. German nutritionists suggest that vitamin E when taken together with food may reduce human exposure to cancer-causing nitrosamines. Vitamin E was effective in preventing their formation especially when used in conjunction with vitamin C.

• Garlic, onions, leeks, and shallots (album vegetables). According to the National Cancer Institute garlic is one of the best foods for protection against cancer. It contains the anti-cancer mineral selenium . which stimulates white blood cell production and induces apoptosis (cancer cell death). Alliums contain compounds that stimulate the production of enzymes that neutralize the free radicals linked with cancer. Alliums contain saponins.which prevent cancer cells from multiplying and they also contain allyl sulfides which increase the production of glutathione S-transferase and other enzymes that enhance carcinogen excretion.

• Garlic, onions, Brazil nuts. whole grains and greens – contain selenium. which causes cancer cells to die before they spread, repairs damaged DNA, protects against free radicals and aids the body’s natural detoxification process.

• Green vegetables, chlorella and spirulina – contain chlorophyll which is an antigenotoxin that inhibits the mutagenic activity of certain chemicals. According to one study published in the journal Mutation Research in 1989, chlorophyll proved to be a more effective antimutagen than all known anticancer vitamins, including vitmains A, C and E.

• Potatoes – are a rich source of alpha lipoic acid – a powerful antioxidant which strengthens and regenerates other antioxidants in the body, especially vitamin E. Biochemist Richard Passwater, Ph.D. suggests that lipoic add may even inhibit the activation of the gene that triggers cancer growth in cells. Potatoes also contain a diverse amount of polyphenolic compounds and protease inhibitors and are a great source of vitamin C.

 • Red peppers, fresh orange juice, broccoli, apple juice, green peppers, grapefruit juice, cranberry juice, papaya and fresh strawberries contain vitamin C which fights free radicals. Vitamin C appears to offer some protection against all cancers.

• Raw spinach and parsley – are good sources of glutathione and chlorophyll Parsley is also rich in polyactylenes which block the formation of tumor-promoting prostaglandins.

• Sea vegetables such as wakame, kombu, hijiki, arame and nori – contain alginic acid which possesses anti-tumor activity, guarding against the initiation and recurrence of cancer.

• Tomatoes, watermelons, red peppers, and carrots contain lycopene which may explain a recent Italian study that found that people who ate raw tomatoes at least 7 times a week halved their risk of several cancers compared to those who ate tomatoes no more than once a week.

• Tomatoes, green peppers, strawberries and carrots – contain p-coumaric and chlorogenic acids which hook onto nitric oxides in the foods we eat and spirit them out of the body before they can form cancer causing nitrosamines.

• Turmeric and cumin – contain curcumin an anti-mutagenic agent that supports the liver in detoxification of carcinogens and helps to block environmental carcinogens.

• A study published in 2000 demonstrated the anti-cancer and antioxidant actions of 3 chemical components of turmeric on leukemia, renal cancer, breast cancer, colon cancer and melanoma. (Ramsewak, 2000)

• Why is Curcumin so beneficial?   “Curcumin appears to be useful in virtually all types of cancer, because of its fundamental mechanism of actions against cancer progression. In particular, preliminary studies suggest that curcumin is likely to inhibit prostate, breast, skin, colon, stomach and liver cancers and is suitable for use in conjunction with chemotherapy. The recommended dosage for curcumin is 200-400 mg one to three times a day.  To enhance absorption take it along with proteolytic enzymes. This combination is best taken on an empty stomach 15-20 minutes before meals or between meals.”  (How to Prevent and Treat Cancer with Natural Medicine p. 175)

• Watercress, Chinese cabbage and turnips – contain phenethyl isothiocyanate which can prevent nicotine-induced lung cancer.

USEFUL FRUIT
• Citrus fruit peels – contain a remarkable anti-cancer substance called D-limonene.Small bits of organic orange peel go well in salads or can be added to any tea. Be sure to cover the tea as it seeps so that the aromatic oils don’t escape.

• Cranberry- contains the anti-cancer constituent, proanthocyanidin. which has an anti-oxidant capability ten times greater than that of vitamin E.

• Figs – contain benzaldehyde which has been shown experimentally to decrease drastically the uptake of thymodine and adenine which leads to a decreased level of ATP within cancer cells, while having no effect on normal cells. It appears it can arrest tumor progression and have a paralytic effect on tumor growth.

• Fruit – contains caffeic acid which enhances production of enzymes that make carcinogens more water-soluble. Fruit also contains ferulic add which binds to nitrates in the stomach preventing production of carcinogenic nitrosamines.

• Grapefruit – contains the flavonoid naringenin which slows the growth of human breast cancer cells.

 • Grapes, many berries and some nuts contain a phytoalexin component calledresveratrol which has shown cancer chemopreventive activity. Resveratrol has been found to act as an antioxidant, antimutagen and anti-inflammatory. It has also been shown to inhibit the development of breast cancer and induce antiprogression activity in human myelocytic leukemia.

• Plant fiber of citrus fruit – has been shown to inhibit metastasis in prostate cancer by competing with tumor cell surface galectins, which are essential for successful establishment of secondary cell colonies.

• Pomegranates, grapes, strawberries, raspberries and nuts contain ellagic acid which blocks the body’s production of enzymes used by cancer cells. In one study an extract of Concord grapes was shown to be as effective as the cancer drug methotrexate in slowing tumor growth. Ellagic acid is particularly effective in the inhibition of lung cancer caused by tobacco.

• Red grapes (especially the seeds), blueberries, blackberries, cherries and grapes-contain oligomeric proanthocyanidins. known as OPC’s, which help to protect DNA from free radicals due to radiation and chemicals and slow down the mutation of cancer cells.

• Rhubarb – has shown anti-tumor activity as a result of two of its compounds, rhein and emodin.

• Tangerines – contain tangertin which inhibits cell-endothelial adhesion, a very important step in the metastatic process of cancer.

USEFUL GRAINS, LEGUMES AND OTHER FOODS
• Barley, bran. brewer’s yeast, brown rice, chicken, dates, green leafy vegetables, legumes, lentils, milk, mushrooms, oranges, split peas, root vegetables, salmon, tuna, wheat germ, whole grains and whole wheat  contain folic acid which increases the production of white blood cells crucial in the defense against cancer. Folic acid in dark green leafy vegetables, oranges and liver may act together with vitamin B12 to prevent injuries to lung tissue and retard the development of cancer among cigarette smokers.

• Butter and ghee – are slow to oxidize and contain butyric acid, an anti-cancer agent, therefore, they are acceptable in moderation.

• Eggs – preferably organic eggs, are one of the best protein foods for people with cancer. Eggs contain all eight essential amino acids and are rich in essential fatty acids, vitamins, minerals, glutathione, sulfur and phospholipids. They are best prepared slow cooked or poached. One or two can be eaten once or thrice a week.

• Fish.  A recent study has shown that omega-3-rich fish oils impede angiogenesis and reduce tumor invasiveness. Although a diet high in animal protein is not recommended for some people moderate portions once or twice a week can contribute to a well-rounded diet.

• Fiber from fruits, vegetables, beans and whole grains.  Since 1980 25 out of 32 studies have shown that fiber protects against colon cancer.

• Flaxseed oil – is rich in alpha-linolenic acid which demonstrates significant anti-cancer properties, especially against breast cancer. Some of the potential anti-cancer agents found in flaxseeds are gallic acid, ferulic acid, chlorogenic acid and coumaric acid.

• Grains contain phytic acid which binds to iron and reduces the free radical effects of too much iron. Whole grains are filled with vitamin E, the B vitamins, minerals, protein, fiber and many other phytonutrients. They contain a substantial amount of insoluble fiber. Fruits and vegetables, on the other hand, contain soluble fiber. The combination of these two forms of fiber promotes bowel regularity and protects against colon cancer. Always use fresh whole-grain flour. The next best thing is to buy the whole-grain flour stored in the refrigerated section of your local health food store and keep it in the refrigerator or freezer at home.

• Green tea. A study conducted by the National Cancer Institute concluded that green tea offers protection against a wide variety of human and mouse tumor-cell lines by causing cell cycle arrest and inducing apoptosis (cancer cell death).

• Olive oil – does not oxidize easily and is also a good source of squalene. the most potent inhibitor of angiogenesis. Buy only unrefined cold-pressed polyunsaturated vegetable oils but do not use them in cooking.

• Sardines, spinach and peanuts – contain CoQ10 which protects against cancer by strengthening the immune system and zapping free radicals.

• Soybeans, chickpeas and other legumes – contain protease inhibitors which reduce certain enzymes in cancer cells.

• Soybeans- contain phytosterols which slow down the reproduction of cells in the large intestine, which may reduce the risk of colon cancer. They also contain glycosides, saponins and isoflavonoids which interfere with the process by which the DNA of cells reproduce, which can prevent cancer from proliferating.

• Soy products. Fermented soybean products such as miso, shoyu, tempeh and natto contain cancer prevention properties that exceed that of unfermented soybeans, soy milk and tofu. Fermented soy products are rich in isoflavones, including genistein, which has been shown to block the growth of a number of cancers.

• What about the dangers of Soy? “Women who have estrogen-sensitive breast tumors should restrict soy intake and should avoid soy isoflavones.  Studies in test tubes and in animals show that the isoflavone genistein stimulates growth of estrogen-receptor positive tumors.  It inhibits the growth of breast cancer cells that lack estrogen receptors, however.”  (How to Prevent and Treat Cancer with Natural Medicine p. 84)

• Yogurt.  Researchers have found that the dialyzate fraction of yogurt possesses anti-tumor activity. Lactobacilli and bifidobacteria found in yogurt produce compounds within the colon that increase beta glucaronization and nitroreductase, which help the body to excrete carcinogens and hormones more efficiently. Yogurt also contains higher levels of free-form amino acids than milk, mainly due to the proteolytic action of the lactobacillus.

HERBAL AND NUTRITIONAL SUPPORT
• Aloe Vera – has been shown to provide a protective effect against injury from radiation treatment.

• A review done at UNC and published in 2000 found that overall it appears that antioxidant nutrients (vitamin C, vitamin E, selenium and carotenoids) especially those from food sources, have important roles in preventing pathogenic processes related to cancer. (McDermott 2000)

• Astragalus. A 1990 study at the M.D. Anderson Cancer Center found that taking astragalus daily increased the body’s ability to kill cancer cells by tenfold. Shi Quan Da Bu Wan, a Chinese formula containing astragalus and ligusticum, has been proved most effective in enhancing cellular immunity, specifically interleukin production by the body.

• Atractylodes- contains 3 cancer-inhibiting components which have demonstrated the strongest activity against esophageal cancer.

• Bromelain and turmeric. In order to have metastases the platelets must aggregate and clump together. Therefore if an individual’s platelet count starts rising above the normal range it is likely that the cancer is spreading. Bromelain and turmeric inhibit platelet aggregation thereby interfering with one of the strategies that cancer uses to spread.

• Chinese skullcap (Scutellaria baicalensis) – inhibits many viruses including tumor viruses and the HIV virus by inhibiting reverse transcriptase. It is also anti-inflammatory and induces cell death in a number of cancer cell lines including two sarcomas and cervical cancer. (Yance, 1999)

• Chlorella – is able to increase the albumin levels in blood. Albumin is the most abundant protein found in the bloodstream, and optimal levels are vital to many of our body’s most important functions.

• Codonopsis stimulates the growth of red blood cells, enhances T-cell trans formation and stimulates phagocytosis.

• Coenzyme Q10 (CoQlO) – is recommended for anyone with cancer who is on the chemotherapeutic drug Adriamycin. Adriamycin depletes CoQlO levels in the heart muscle, which can lead to heart damage (this is a serious side effect of this drug). When CoQlO is administered in conjunction with this drug, heart damage does not occur.(Yance, 1999)

• Ginseng (Panax) – can not only stop the growth of malignant liver cells in the test tube, but can turn them back to normal. In animal studies panax ginseng has been shown to inhibit metastases to the lung and liver and to reduce elevated platelet and fibrinogen levels caused by the tumor cell lines.

• Ginseng (Siberian) Scientists have found that it produces an immune-boosting effect on white blood cells in both cancer patients and healthy controls. This points to Siberian ginseng’s ability to stimulate resistance and boost the immune system in patients undergoing chemotherapy and radiation for breast cancer.

• Grapeseed extract. According to Gaynor, studies have shown that this anti-oxidant is 20 times more powerful than vitamin C and 50 times more powerful than vitamin E at scavenging free radicals.

• A study published in 2000 found that grape seed proanthocyanidin extract (GSPE) is highly bioavailable and provides significantly greater protection against free radicals and free radical-induced lipid peroxidation and DNA damage than vitamins C, E and beta-carotene.  GSPE was also shown to demonstrate cytotoxicity towards human breast, lung and gastric adenocarcinoma cells, while enhancing the growth and viability of normal human gastric mucosal cells. (Bagchi et al 2000)

• Isatis – contains indirubin which possesses strong anticancer activity and is particularly effective against chronic myelocytic leukemia. Indirubin was also found to inhibit breast and lung cancer. (Yance, 1999)

• Licorice (Glycyrrhiza glabra) – contains glycyrrhizin which posses blocking ability against tumor-promoting agents. A recent study in Japan demonstrated that glycyrrhizin can inhibit liver cancer caused by hepatitis. (Yance, 1999; Kumada, 2002)

• Lipoic acid. German research shows that lipoic acid activates T-cell function, regenerates glutathione and prevents oncogene activation. It is also useful in treating all liver disorders. Lipoic add can actually regenerate not only the liver but also nerve tissue. Cancer, being a sugar-lover, causes an increase in glycation, the modification of a protein by the action of a sugar molecule. Lipoic add protects against and reduces glycation. Lipoic acid can increase immune surveillance and protect the bone marrow, the liver and the kidneys from chemotherapy-induced toxicity.

• Minor Bupleurum Formula. This formula has been found extremely effective at inhibiting cancer by enhancing the immune system, inducing apoptosis and inhibiting angiogenesis. It is most useful in breast and liver cancers, but can also be used to treat colon cancer. Bupleurum saponins exhibit anti-inflammatory activity similar to prednisone. (Yance, 1999)

• Mistletoe (Viscum album). Iscador fermented extract of Mistletoe, reduces the leukocytopenia (subnormal number of leukocytes in the blood) produced by radiation and chemotherapy. Mistletoe is tumor-inhibiting and cytotoxic to a number of different tumor types.

• Shiitake, reishi and maitake mushrooms – contain polysaccharides- plant chemicals that have been found to be effective in preventing tumor growth and in strengthening the immune system. Maitake mushrooms stimulate immune function and also inhibit tumor growth. Shiitake contains the polysaccharide lentinan which is known to boost the activity of the immune system. Shiitake fosters many immune-enhancing activities including stimulation of macrophages, increased cytotoxic activity of macrophages, increased production of interleukin-1 and -2, increased T-lymphocyte production, and enhanced CD-4 cell function.

• Medicinal plants that have exhibited antitumor action due to modulation of programmed cell death and arrested proliferation are trichosanthes, soy, garlic, ginger and green tea.(Thatte, 2000)

FOODS TO AVOID
• Avoid beef. pork and lamb; processed meats and liver. In a large study at Harvard it was shown that the relative risk of colon cancer in women who ate beef, pork, or lamb as a main dish every day was about two-and-a-half times that of women who ate such foods less than once a month. Processed meats and liver were also associated with increased risk, whereas fish and chicken without skin were related to decreased risk. The conclusion was that a high intake of animal tat increased the risk of colon cancer.

• Avoid all foods that contain olestra. When traveling through the body olestra takes with it the fat-soluble vitamins A, D, E and K and it also reduces circulating levels of carotenoids, including beta-carotene and lycopene.

• Avoid all processed fats and oils or any foods containing processed oils including hydrogenated or partially hydrogenated products. Trans fats or hydrogenated oils found in margarine and vegetable oils are linked with an increase in breast cancer. Avoid canola oil, safflower oil, corn oil, soybean oil, sesame oil as well as margarine. Avoid all commercial cookies, crackers, snack foods, frozen foods, deli foods, mayonnaise, fried foods and all foods labeled “partially hydrogenated.”

• Avoid frying, barbecuing or broiling meat, poultry or fish – especially when using polyunsaturated fats such as safflower or corn oil as it can produce potential carcinogens called heterocyclic amines which have been linked with many forms of cancer. If you do occasionally fry food, use olive oil or butter and do not cook to a point where your food becomes burnt or blackened.

• Avoid refined carbohydrates such as white sugar and white flour. They can cause abnormally high levels of blood glucose, a common factor in cancer. The excess glucose feeds the fermentation process of cancer cells and suppresses the immune system. Elevated glucose levels are seen three to eight times more often in people with active cancer. A study on diet and breast cancer showed a relationship between an excess of starch intake (refined pasta and bread) and breast cancer.

• Avoid processed soy foods – such as soy grits, textured soy protein and soy oil which have been processed using hexane a toxic chemical used frequently as an extraction agent.

• Cancer patients should avoid coffee.  For those in good health, however, organic coffee is fine in moderation.

• Cancer patients should avoid alcohol. Alcohol depletes glutathione levels and stresses the liver. For healthy individuals a glass of organic red wine with a meal is fine. Wine is a rich source of two very important anti-carcinogens – PCOs and resveratrol.

• Do not smoke. Countless studies have shown significant increase in the risk for cancers of the lung, bladder, esophagus, stomach and pancreas in smokers as compared to nonsmokers.