Since cancer has become the plague and one of the greatest fears of the modern technological, chemical age and, overall, cancer treatment, other than for certain malignancies, has not to date been very successful, prevention of cancer is the only sensible approach. The relationship of diet to cancer came of age in the 1980s. With our new knowledge, we can clearly now do something about the threats of cancer and our future. Caring for ourselves and others as if we really love life and have a desire to live will win over all possible disease!
Chapter 11, Environmental Aspects of Nutrition, contains a fairly detailed discussion of cancer—its genesis, potential offending agents, dietary concepts, prevention ideas, and so on. Here I want to focus more on general nutrition and supplements and their importance in preventing cancer.
Two decades ago, it was difficult to find any major institutions, doctors, or groups like the medical associations or the American Cancer Society, that would admit that there were any ties between cancer and nutrition. Now the nutritional and environmental influences on the genesis of cancer, the second biggest killer of the American adult population, have been fairly well accepted as key components in this disease. A big breakthrough came with the 1977 Senate Select Committee’s Dietary Goals for the United States, listing cancer as one of the major degenerative diseases (cardiovascular disease and diabetes are others) that are linked to improper diet. The committee’s suggestions of lower fat, higher fiber, and more natural foods are definitely a part of the cancer-prevention diet. An important report called Diet, Nutrition and Cancer, compiled by the National Academy of Sciences and released in 1982, gave further credence to the relationship between diet and cancer and offered more specific dietary suggestions. And in 1988, the U.S. Department of Health and Human Services published a major manuscript by C. Everett Koop, M.D., entitled The Surgeon General’s Report on Nutrition and Health. It discusses the relationships between nutrition and our common degenerative diseases, including cancer.
But cancer is a multifactorial, multidimensional disease. While nutritional and environmental influences are definite components, physiological, social, emotional, psychological, and spiritual factors are also important. Therefore, the prevention and treatment of cancer must deal with all of these aspects of life.
The aging process itself increases cancer risk, but particularly if we do not take good care of ourselves. Poor nutrition can lead to many functional problems, such as lowered immunity and slower cell repair. The increased exposure to carcinogens is no help either. (See more on this in the Anti-Aging Program). To much of the medical profession, cancer prevention means primarily early detection—more exams, x-rays, mammograms, and biopsies—so that the necessary surgery, drugs, and radiation can be applied sooner to prevent an untimely death. However, prevention of cancer is much more than early detection—it means not creating the disease. A good diet and stress management are important cancer preventives. A strong, healthy immune (defense) system is also an essential part of this plan (see the preceding program on Immune Enhancement). With a strong immune system, even the few cancer cells that might be regularly generated would be easily removed from the body. Put simply (according to current thinking), it takes both the disease of the cells and the failure of the immune system together to create cancer—in other words, the effect of potential carcinogens on an already unstable body.
Michio Kushi, author of the in-depth text The Cancer Prevention Diet, believes that cancer is caused not so much by carcinogens per se as by the imbalance in the body caused by improprieties of diet that allows the agents to create problems. He advocates the “unified theory of disease,” which sees the internal imbalance between yin and yang as the primary cause of cancer and most diseases. It is the “duality,” or seeing of body parts or diseases as separate from our entire being, that allows us to treat even the mildest of symptoms as an enemy and not as an ally trying to guide us in a new direction. As we continue to approach our health in this way, we create further diversions from unity and manifest more-difficult-to-treat acute and chronic problems. Cancer itself, as is true of most disease, can be seen as a lack of harmony with our environment and a diversion from our inner truth.
This program is suitable for most everyone, especially those in a high-cancer-risk group. That includes men and women over 40 or 50 years old and people with a family history of cancer, especially women with a family history of breast cancer. Smokers, people with a dietary history that includes cancer risks, and those who have been exposed to known carcinogens will also benefit.
What really causes cancer? Is it a virus or genetic code, the effect of carcinogens on cellular growth, or a weakened immune system? Is it a poor, “cancer-promoting” diet? Or does it have to do with the psychological factors influenced by stress, poor attitude, or low self-esteem? We do not really know; cancer seems to be linked to all of these factors. Family history is definitely a factor, and if someone in our families has had cancer, that should increase our watchfulness for this disease as well as encourage us to use early detection procedures.
Discussion of cancer risks and promoting factors could easily fill a book. I want to keep it simple. Below I list the eleven main cancer risks, followed by a more extensive discussion of various factors that may add to our chances of developing cancer sometime in our lives. One of the difficult tasks in researching many cancer risks is that cancer can often take 30–40 years from the time of exposure to a carcinogen for it to manifest as a physical tumor. But the following list clearly shows that the promotion of cancer involves almost exclusively diet, environment, and lifestyle. Problems that result from pharmaceutical medicines or viral conditions that weaken immunity and allow cancer to develop more easily are probably rarer, and usually even the factors that predispose us to these conditions are areas over which we have some control.
- Dietary excesses —fats (mainly saturated, fried polyunsaturated oils, and
- Undernutrition —deficient fiber and nutrients such as vitamins C and E,
- Occupational chemicals
- Food chemicals —pesticides, additives, hormones
- Air and water pollution
- Excess sunlight and radiation
- Certain pharmaceutical drugs —estrogen, metronidazole (Flagyl),
- Psychological influences —such as personal changes, loss of loved one, grief, divorce
cholesterol); protein; obesity (calories)
lindane (Kwell), or griseofulvin
Smoking, mainly of cigarettes, is a primary cancer risk and is correlated with nearly all lung cancer. It is also a factor in cancers of the mouth, throat, and larynx and possibly others. Pipe and cigar smoking produces higher incidences of mouth cancer but less of lung. Cigarette smoke acts synergistically with alcohol, asbestos, and other carcinogens in air, water, and food to further increase cancer risk and rates. It is likely that naturally grown tobacco rolled in untreated paper poses less cancer risk; the chemical production and treatment processes involved in manufacturing a pack of cigarettes are definitely an added cause for concern. Regular marijuana smoking may also be a factor in cancer, though more research on this is needed. Cigarette smoking is clearly the largest and most preventable cancer risk.
Excess fats in the diet definitely increase the incidence of breast, colon, and prostate cancer and possibly others, such as uterine or ovarian cancer. The fats of most concern include saturated animal fats, as found in meats and dairy products; fried or rancid oils; hydrogenated and refined oils, and cooked polyunsaturated fatty acids (PUFAs). Rancid oils and foods cooked in oils cause more free-radical irritation (as do high amounts of PUFAs), mainly from lipid peroxides, and these act as mutagens and carcinogens. Excess protein in some studies correlates with cancer rates, but most of the higher protein foods also contribute to higher fat levels and this type of diet will often lead to more general body congestive and degenerative processes.
Obesity is definitely correlated with higher cancer rates. Colon, rectum, and prostate cancer rates are higher in obese men, while obese women have increased risks of cancer of the breast, cervix, uterus, ovary and gallbladder. It is not totally clear whether the risk is posed by the obesity itself, higher caloric intake, or by the many associated factors, both nutritional and psychological (overweight people tend to hold things in).
Deficiencies of many nutrients are implicated in some cancers. Low fiber in the diet is probably the biggest culprit, mainly in the increasing problem of colon cancer. Slow transit time through the intestinal tract, allowing more contact to carcinogens, may be the main factor here. Many specific nutrient deficiencies have been correlated with various cancers. Vitamin A and beta-carotene deficits increase the incidence of lung and mouth cancer, especially among cigarette smokers, and are also implicated in cancers of the skin, throat, prostate, bladder, cervix, colon, esophagus, and stomach. Also of concern is selenium deficiency, which we now know may increase the risk of many cancers, mainly of the breast, lungs, colon, rectum, and prostate, as well as skin, pancreas, and intestinal cancer and leukemia. Vitamin C may reduce the carcinogenicity of nitrosamines and other chemicals; vitamin C deficits may increase cervical, bladder, stomach and esophageal cancers, as well as the general carcinogenic process. Vitamin E deficiency definitely weakens the body’s ability to balance rancid oils and free radicals, and this increases cancer risk. Other mineral deficiencies implicated in cancer include molybdenum deficiency in esophageal and stomach cancer; zinc deficiency in cancer of the prostate, colon, esophagus, and bronchi and general immune system weakening; and possibly iodine and iron deficiencies.
Occupational chemicals are a topic of great concern. Many workers at home or in jobs are exposed to a wide range of chemicals with varying carcinogenicity. Possible agents include nuclear radiation and fallout, chemicals used in dry cleaning and other cleaning supplies, benzene, coal tar and its derivatives, asbestos, arsenic, PVC, gasoline and petroleum products and other hydrocarbons, pesticides, cosmetic chemicals, and many others. A more detailed discussion is included in Chapter 11, Environmental Aspects of Nutrition. Cigarette smoking also increases the risks from these occupational hazards.
Food chemicals are another big topic. There are many possible carcinogens, most of minimum risk but often cumulative, and we have much to learn about possible interactions of multiple carcinogens. Chemicals may be added to food during growth, manufacture, or preparation, and some are even made by the foods themselves or in combination with other microorganisms.
Additives—food colors, flavors, nitrates, and nitrites.
Saccharin—implicated (still unclearly) in bladder cancer.
Hormones—in meat, possibly even DES, which was recently banned.
Pesticides—sprayed on foods before and after harvesting.
Aflatoxin—produced by molds on peanuts, other legumes, and possibly other foods; may cause liver cancer.
Coffee—questionably implicated in bladder cancer. Decaffeinated coffee may be treated with carcinogens such as trichloroethylene or methyl chloride.
Sugar—may weaken immunity and increase cancer risk.
Nitrates and nitrites—common in preserved and smoked meats, such as ham, bologna, salami, corned beef, hot dogs and bacon; may convert to carcinogenic nitrosamines.
Pickled or salt-cured foods—may influence stomach and digestive lining.
Barbecuing—creates protein changes and production of benzopyrene, a mild carcinogen. Charbroiled meats and burnt toast may also be concerns.
Mushrooms—may contain toxic hydrazines.
Potatoes—when bruised or green.
Other foods—cottonseed oil, cocoa, mustard, black pepper, horseradish, fava beans, parsley, celery, alfalfa sprouts, parsnips, and figs all may contain mild carcinogenic substances. (Some of the agents produced by these plants may act as natural pesticides.)
Water pollution may involve a great many chemicals; metals, pesticides, PCBs, vinyl chloride, carbon tetrachloride, and gasoline are a few examples. Contamination of underground water tables may spread rapidly. Air pollution may also contain many carcinogenic substances from the nitrous and sulfur gases to hydrocarbons, carbon monoxide, and so on.
Excessive sunlight is implicated in skin cancer and excess radiation for cancer in general. Light-colored skin, cosmetic chemicals, and nutrient deficiencies, as well as the changes in Earth’s ozone layer due to pollution, may also be factors in skin cancer. X-rays can produce leukemia and other cancers; this probably involves other precipitating factors, such as exposure to other carcinogens and/or low levels of necessary antioxidant nutrients.
Pharmaceutical drugs have a cancer-producing potential that has been well studied, at least in animals. Estrogen hormones, for postmenopausal use or as birth control pills, are factors of concern in women, though the latest research suggests less correlation with both breast and uterine cancers than was previously thought. Metronidazole (Flagyl), a commonly used antibiotic for bacteria and parasites, poses cancer risks, as does lindane (Kwell), a pesticide used on the skin for mites and lice. Griseofulvin, an antifungal agent, also poses mild cancer risks. In my opinion, steroid drugs, commonly used for suppressing all kinds of natural and unnatural body responses, have definite potential through immune suppression for increasing cancer risk. I believe there should be more research done regarding the implication of steroid use in the incidence of postinfections and cancer.
Alcohol has also been implicated in some cancers, such as cancers of the mouth, larynx, esophagus, and pancreas. These risks are increased when alcohol use is combined with cigarette smoking. Alcohol abuse is also often associated with poor diet and many nutritional deficiencies.
Viral diseases have been implicated in a variety of cancers. For years, genital herpes infections were thought to increase cervical cancer rates. It is now shown that the human papilloma virus responsible for the common venereal warts are more closely tied to cervical cancer than are herpes viruses. Vitamin A, folic acid, and selenium deficiencies may also be involved in cervical cancer. Cytomegalic and Epstein-Barr viruses have been considered as factors in cancer, possibly through mutagenic cellular effects, and may contribute to certain lymphomas or leukemias.
Psychological factors and the role they play in cancer is a fascinating topic; an increasing amount of research is being done in this area. It is clear that in some cases, a significant loss or perception of loss of a loved one occurred between one and two years prior to the diagnosis of cancer. This gives us another insight into the idea that it may take years, even 30–40, for a cancer to develop; cancer can also be a rapidly occurring and progressive disease.
There may indeed even be a cancer-type personality. The cancer disease process may be more prevalent in individuals who do not easily form close bonds or love relationships and do not easily express their feelings such as anger or frustration or who internalize most of their feelings, not necessarily aware that they even have any. These people might also show passive, compliant, or overly nice behavior and have low self-esteem. When such people experience unresolved loss of a loved one through death or divorce, a sense of helplessness or hopelessness may set in and weaken the immune system. Research seems to indicate that the feisty, tough scrappers who do not easily accept others’ opinions or condemnation of themselves and can readily express their own feelings do much better with cancer, recovering more rapidly and more commonly than the more passive, accepting types. Bernie S. Siegel, M.D., discussed this area of personality and cancer extensively in his wonderful book Love, Medicine and Miracles. He reported that children who developed cancer also had shown some of the aforementioned traits, with a definite correlation with loss or perceived loss of a loved one—usually a parent but possibly a sibling or even a dog—in their early years. Excessive stress and psychological traumas all influence our immunity and increase our cancer risk. It is possible that the relationship between cancer and psychology can be summarized by the statement that cancer or any stress-related illness can result from a deep or chronic challenge or threat to our personal identity, roles, or relationships.
It is clear that cancer is not a simple disease to understand, diagnose, or treat. There are many types of cancer, each with its own set of predisposing factors, growth rates, treatment options, and so on. What is common to all, though, is the uncontrolled growth of aberrant cells which endangers healthy tissues, function, and life. Still, each person with cancer is an individual, and I believe that in most situations, many factors are involved in the genesis of the cancer. Our focus in this program, however, is to minimize our risks and prevent cancer, which now afflicts more than one in every four people at some time in their life and eventually touches nearly every family in the Western world. It is obvious that we should avoid smoking and the smoke of others, minimize the use of carcinogenic chemicals at home and at work, and do our best to breathe clean air and drink good water. We should also minimize our exposure to radiation.
Reducing time in front of the television and computer screens will lower our exposure. Not living near nuclear power plants is important; limiting airline flights may help. Exposure to medical, dental, and chiropractic x-rays can be decreased. Many practitioners in each of these professions overuse regular radiation to follow patients. Routine chest x-rays for hospital admissions, for detecting tuberculosis or other lung or heart disease, or for employment are often unnecessary. Routine dental x-rays can be taken every five years instead of at the usual two-year intervals. Chiropractors often x-ray the entire spine; this can be very helpful, but it should not be done more than once or twice in a decade. Care can be taken to use the best equipment with the least radiation exposure and leakage. Whenever possible, x-ray films should be shared among practitioners, rather than each one taking new films.
- Fear of the future in a world overwhelmed by individual unconsciousness is a cancer generator. If we are a contributor to our planetary demise, then cancer or other diseases may be the interest on our investment.
In addition to all of these things to avoid, there are also many positive things to emphasize to reduce our cancer risks. Diet (low fat, high fiber) and nutrients (extra vitamins A, C, and E, and selenium) can be very helpful. These are discussed in more detail below.
Positive steps toward early detection of cancer are also important. Although healing from cancer may be difficult, it is clear that the earlier it is found, the better the chances for survival (though this viewpoint is not universal). The current consensus is still that regular breast self-exam, Pap smears, prostate exam and sigmoidoscopy, colonoscopy (looking in the colon), and possibly routine mammography, may be to our advantage in early detection. Of course, it is advantageous only to those who have cancer; the high percentage of people with normal results have gone through the expense of time and money and often some pain.
It is important to keep ourselves physically and psychologically fit through exercise and working on our attitude. Regular exercise definitely improves our attitude and energy for life, as well as being a good immune supporter. When we are distressed or confronting important issues, dilemmas, or crises, it is wise to seek help to process our feelings if we are not able to handle them fully ourselves. A good friend and confidant can help, or a trained therapist may be beneficial. We all need to break the association of seeing a psychologist or therapist with being “crazy” and, instead, look at therapy as an important part of preventive medicine. Being able to deal with life’s stresses as a challenge rather than with despair, helplessness, hopelessness, or other internalized feelings that make us feel that there is no escape is essential, not only in preventing cancer but for general health as well. Most of us still play out childhood patterns and our individualized attitudes of trust and self-image affect our adult relationships and everyday life, and this does not serve our best or most-evolved interests. Astute, interactive therapy and/or hypnotherapy can help point out these old patterns and replace them with new, more helpful ones to improve our potential for experiencing love and success in most areas of our lives.
Stress management techniques, relaxation and visualization exercises, and meditation are all useful self-help processes that may be learned. Developing a spiritual or universal perspective about our world and our involvement with life is also important for interpreting and coping with challenging experiences such as cancer. Michio Kushi suggests that a complaining, arrogant, rigid, and competitive character makes one more susceptible to degenerative disease, while a healthier approach may be peaceful, grateful, flexible, and cooperative.
The Cancer Prevention Diet
usually involves a moderate to major change in the average person’s dietary habits. Even the most traditional nutrition books now suggest the following as the main components of the Cancer Prevention Diet:
- Lower fat intake to about 20 percent of total calories (25–30 percent is more realistic; the average has been 42 percent). A maximum of 65 grams of fat per day is suggested; 50 grams is better. That represents 450 calories (9 cal./g., 9×50=450) of fat daily, or 20 percent of a 2,250-calorie diet. More of the fats should be the mono- and polyunsaturated types with a reduction of saturated fat intake, and little or no consumption of refined and heated oils.
- Increase dietary fiberto improve colon function mainly by increasing complex carbohydrates in the form of whole grains and lots of vegetables, along with some fruits, all of which contain high amounts of many of the important nutrients.
- Increase fresh fruits, vegetables and whole grains.
- Maintain ideal weight and avoid obesity.
- Avoid smoking.
- Avoid smoked, salted, pickled and barbecued foods.
The seven dietary suggestions of the American Cancer Society (ACS) are very similar:
- Avoid obesity.
- Cut down on total fat intake.
- Eat more high-fiber foods, including whole grains, fruits, and vegetables.
- Include cruciferous vegetables , such as cauliflower, broccoli, and cabbage.
- Include foods rich in vitamins A and C.
- Lower alcohol consumption.
- 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.
Cancer Prevention: Dietary Suggestions
|Emphasize:||Avoid:||(organic if possible)|
|cruciferous vegetables||high-fat foods|
|other vegetables||hydrogenated fats|
|whole grains||synthetic or high-chemical foods|
|fish (untreated)||barbecued foods|
|legumes||excess polyunsaturated oils|
|some nuts and seeds||alcohol|
|seaweeds/sea vegetables||high-calorie diets|
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:
- 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.
- Avoiding or neutralizing carcinogens —vitamins C and A, selenomethionine, and the amino acid L-cysteine.
- 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.
Is an antioxidant.
Stimulates T lymphocytes to produce interferon, which decreases virus reproduction.
Supports thymus function, specifically in strengthening the cytotoxic and killer T lymphocytes, and supports antibody responsiveness.
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.
Reduces stomach, esophageal, and bladder cancers by means of its multiple protective effects on mucous membranes (this needs more research).
Has been shown, along with folic acid, to minimize cervical dysplasia and cancer, where these nutrients have been measured at reduced levels.
Vitamin E functions best with adequate levels of selenium as selenomethionine, and vice versa, as antioxidants and cell membrane protectors. Vitamin E is found naturally in vegetable oils and nuts and seeds, with a little in the germ of whole grains such as wheat and rice. It reduces carcinogen production and strengthens immune cells and cell membranes against the penetration of viruses and toxic chemicals.
Selenium helps regulate the glutathione peroxidase enzyme, a strong antioxidant enzyme. Low selenium levels in the soil and in our body are clearly associated with increased rates of leukemia and cancers of the breast, lungs, colon, rectum, prostate, ovary, skin, and pancreas. If soils are low in this mineral, the foods grown in them will not contain much selenium. It is wise to increase selenium-rich foods, such as the whole grains and legumes or brewer’s yeast, if tolerated, as well as to take a supplemental 100 mcg. per day to be safe. High copper levels can reduce selenium absorption and utilization as well.
Zinc is another important mineral. It is an immune supporter and is important to the formation and function of many enzymes that work on detoxifying chemicals. Low levels of zinc in the body have been associated with higher rates of prostate, bronchial, esophageal, and colon cancers. Low levels of molybdenum in the soil have also been shown to be associated with increased levels of esophageal cancer. Calcium protects against colon cancer by protecting and correcting irregular cells in the colon. Other minerals that may have anticancer qualities include iron and iodine.
Fiber is another important anticancer substance and is a part of many foods which can also be taken as a supplement, such as psyllium seed husks or the bran of wheat or oats. Adequate dietary fiber improves intestinal transit time and binds carcinogens, thus reducing exposure to them. A high-fiber diet clearly reduces the incidence of colon cancer and diverticular disease (and may lower blood cholesterol), whereas a high-fat, low-fiber diet increases the risk of colon, breast, and other cancers.
Lactobacillus acidophilus is, I believe, a useful anticancer agent, mainly to prevent colon cancer. Lactobacilli cultures in the colon decrease other bacteria that can change bile salts into irritating carcinogens, as well as reduce yeast overgrowth and inflammation that result from these organisms, which also contribute to allergies and immune suppression.
A few other immune-supporting nutrients include gamma-linolenic acid (GLA), extracted from evening primrose oil or other sources; GLA helps increase certain prostaglandins that support lymphocyte immune activity, and there is some indication that it has an anticancer effect. More research is also needed on the anti- or procancer effects of L-arginine, a semiessential amino acid. L-carnitine may also be helpful for improving fat utilization, as poor fat metabolism and free-radical fat molecules can cause cellular and tissue irritation. Organic germanium may also be effective in cancer prevention, although it is more clearly useful in cancer treatment.
BHA and BHT are antioxidant food chemicals (preservatives) that some researchers feel have potential to lower chemically induced cancers; other authorities believe these chemicals are too toxic to use as supplements. I prefer the natural antioxidant nutrients that are commonly found in foods.
Garlic and echinacea are thought to help support immune function, and thus may play a role in preventing cancer. Aside from garlic, no herbs have been studied well enough to determine their possible cancer preventive effects. (There may be some herbs, both Western and Eastern, that have anticancer effects; these will be discussed more in Staying Healthy with Modern Medicine, my next book, which will include cancer therapy. Among those that may have properties effective in preventing cancer development are intestinal detoxicants, such as the algins and kelps; herbal blood cleansers (alteratives) such as chapparal, cayenne pepper, burdock and yellow dock roots, and blue flag root; colon cleansers such as rhubarb root and black walnut; diuretics and kidney cleansers such as cleavers, uva ursi and dandelion; lymph cleansers such as echinacea; and nutritives, such as alfalfa.
The following program is particularly geared to protect those with added cancer risks, although it may also be used periodically, for a month or two several times yearly, for the average individual. With aging, or during times of stress or emotional traumas, this program may also be helpful. The following values can include nutrients in the diet and/or additional supplements.
Cancer Prevention Nutrient Program
|Vitamin A||5,000–10,000 IUs||Iodine||150–200 mcg.|
|Beta-carotene||15,000–30,000 IUs||Iron||10–20 mg.|
|Vitamin D||400 IUs||Magnesium||300–600 mg.|
|Vitamin E||400–800 IUs||Manganese||5–10 mg.|
|Vitamin K||150–300 mcg.||Molybdenum||250–500 mcg.|
|Thiamine (B1)||50–100 mg.||Potassium||300–600 mg.|
|Riboflavin (B2)||25–75 mg.||Selenium, preferably||200–300 mcg.|
|Riboflavin-5-phosphate||25–50 mg.||as selenomethionine|
|Niacinamide (B3)||50–100 mg.||Silicon||100–200 mg.|
|Niacin (B3)||50 mg.||Vanadium||150–300 mcg.|
|Pantothenic acid (B5)||250–500 mg.||Zinc||30–60 mg.|
|Pyridoxine (B6)||50–100 mg.|
|Pyridoxal-5-phosphate||25–50 mg.||Lactobacillus||1–2 billion organisms|
|Cobalamin (B12)||100 mcg.||Garlic oil or powder||2–3 capsules|
|Folic acid||800 mcg.||Essential fatty acids,||2–4 capsules|
|Biotin||500 mcg.||or Flaxseed oil||1–2 teaspoons|
|Vitamin C||3–6 g.||Gamma-linolenic acid||4 capsules|
|Bioflavonoids||250–500 mg.||or 200–300 mg.|
|L-amino acids||1,000 mg.|
|Calcium||850–1,200 mg.||L-cysteine||250 mg.|
|Chromium||200–400 mcg.||L-carnitine||500 mg.|