NUTRITIONAL GUIDELINES FOR PEOPLE WITH CANCER
Presenters: Jeffrey Bland, Ph.D. and Daniel Nixon, M.D.
Moderator: Susan Lord, M.D.
Session: F5; June 11, 1999| Conference Home Page | Presenter Bios | CMBM Home Page |
I. Abstract
The "Do's" and "Don. ts" of nutrition are a popular topic of discussion in society these days. Dietary issues are of particular concern for the cancer patient, whose immune system is compromised. The body requires energy and strength to fight disease and maintain homeostasis as best as possible during cancer treatment. Food and nutrients are the source of this energy. Nutrition is a major concern for cancer patients who need accurate information in order to make informed dietary choices.
II. The Cancer-Related Issue Addressed
In this session, Dr. Jeffrey Bland, Ph.D., Founder and Director of Health Comm International, a research and clinical facility that trains doctors and health care providers, focused on nutrition specifically for the cancer patient. He addressed metabolic considerations in the cancer patient, distribution of macronutrients and dietary supplements. Dr. Daniel Nixon, M.D., is President of the American Health Foundation, a cancer treatment center, and a professor at the Medical University of South Carolina. He concentrated on cancer prevention and presented his Risk-Reduction Program while discussing the epidemiological and clinical support behind dietary recommendations. Dr. Gabriel Feldman, a public health specialist from the American Cancer Society summarized and gave his perspective on the information presented by the two preceding speakers. Dr. Susan Lord, M.D., a family practitioner and staff member at The Center for Mind-Body Medicine, served as moderator for the session. The speakers presented facts and clinical trial data on nutrition coupled with their own findings and interpretations. The goal of the session was to provide practical advice to make dietary changes and select nutritional supplementation. The take-home message was the importance of achieving balance in the body and recognizing variation and individuality among people.
III. The Program Presented by Dr. Bland
A. Background
Dr. Jeffrey Bland spoke extensively Thursday, June 10 on the molecular biology of cancer in relation to nutrition. He incorporated environmental issues, immunological concerns and toxicities into the lecture. (See notes on "What Do We Know About Nutrition And Cancer?"; Session T2.) The focus of this presentation was nutrition specifically in the cancer patient. How we eat and justify our behavior is a personal choice. It is hard to make a generic statement or offer middle of the road advice about nutrition. Different types of cancer affect the body differently and require varied nutrient needs. There are a few background principles to keep in mind when considering nutrition. First, cancer is not inevitable. Second, the body is not determined to get cancer because of "bad" genes. Non-genetic factors do exist and contribute to the development of disease. Finally, there are many steps to potential recovery due to the body's defense mechanisms.
B. Details
Although dietary information should be individualized, there are certain metabolic considerations to take into account with all cancer patients. A cancer patient may experience all, some or none of these metabolic abnormalities. One common metabolic concern involves regulation of glucose and insulin. The hypermetabolic state of cancer cells effects glucose management. Cancer cells shift to anaerobic glycolysis and produce acid metabolites. This causes the cells to become sugar hungry and the body sensing mechanisms say 'feed me'. Conditions such as hypoglycemia and dysglycemia may result. Cachexia, the body wasting many cancer patients experience, often occurs due to an increase in pro-inflammatory cytokines. These cytokines cause an increase in tumor necrosis factor which leads to an increased release of appetite suppressants. The result is a hypermetabolic state and muscle wasting of the individual. The side effects of chemotherapy such as appetite aversion and metallic taste in the mouth contribute to decreased food consumption and cachexia. A third metabolic consideration is the decrease in pH due to acid metabolite accumulation that changes enzyme functions. Changes in electrolyte transport across membranes also contribute to muscle wasting, as well as twitching and cramping. The magnesium-potassium pump in membrane pores requires energy in the form of ATP. When the pump is impaired, sufficient amounts of minerals and compounds are not transported across cell membrane which results in muscle changes. Finally, the shift in redox reactions and oxidative stress of cancer cells are additional metabolic concerns and contribute to the hypermetabolic state of the patient.
Dr. Bland recommends a high calorie, low fat diet, averaging about 35 kcal/kg body weight. The goal of such a diet is to maintain nitrogen balance, avoid fasting and accrue 'good' calories. His recommended distribution of macronutrients is broken down into 50% complex carbohydrate, 20% protein and 30% fat. The carbohydrates should be low in simple sugars in order to normalize glucose. One should try to avoid juice or canned and concentrated fruit. The best primary sources of protein are vegetables, such as grains and legumes, which are also a good source of complex amino acids. Soy and fish are easy to digest and preferable to meat or chicken protein. Fats should primarily come from omega-3 and omega-9. Examples of omega-3 fats include seeds, nuts, flax seeds and fish oil. Extra virgin olive oil, a monounsaturated fat, is an excellent source of omega-9.
Vegetables are a key source of carbohydrates containing vitamins, minerals and anti-oxidants. A diet should include as wide a variety as possible. Nutrient rich groups include crucifers, (cauliflower, broccoli, cabbage) root vegetables, sea vegetables, dark green leafy vegetables, tomatoes, and carrots. Carrots are an optimal source of beta-carotene, and spinach contains leucine and folate, all sources of anti-oxidants for the body. Patients can find protein in certain protein-rich vegetables, lentils, mung and kidney beans. Buckwheat, also notable for its low gluten content, whole grain rice and soy are other recommended protein sources. Mung and kidney beans also contain fiber and omega-3 oils. Fiber is also important to include in the diet. Fiber exists in soluble and insoluble forms. The recommended breakdown is 65% of the insoluble form, such as grains, and 35% of the soluble form, found in legumes.
Opinions are divided on the topic of dairy products. 'To eat or not to eat' dairy is a question pondered by many cancer patients. Dr. Bland suggested cultured dairy products containing live cultures such as acidophilus and bifidus. Bacteria normally live in the gut but may not be able to perform their normal functions in a cancer patient. These supplements can help repair the bowel.
Dietary supplements compose the most controversial area of nutrition. Dr. Bland reiterated the importance of staying within safe dosing limits with any product. He stressed that the information he presented was his opinion. B-vitamins boost the integrity of the immune system and repair micronucleic damage of the host cell. B-vitamins, and recommended doses, include folate (600 m g), B-6 (5-10 mg), B-12 (100 m g), betaine (100-500 mg). Patients need to be aware of certain drugs that are B-vitamin antagonists. Vitamin A is a retinol compound that is formed from beta carotene in cells in the intestine. Cancer patients under convert beta carotene to vitamin A and might consider supplements. Antioxidants support mitochondria functions and DNA repair. These supplements include manganese (5 mg), zinc (50 mg), selenium (200 m g), vitamin E (400-800 mg), coenzyme Q-10 (20-50 mg), lipoate (100-500 mg), vitamin C (500-1000 mg), N-acetylcysteine (100-500 mg). Dehydroepiandrosterone (DHEA), thought to have a role in hormone balance, hyaluronic acid and shark cartilage, possible mucopolysaccharides, are a few of the more controversial supplements. Some preliminary studies have been done on the anti-cancer and anti-oxidant effects of melatonin. Melatonin (0.5-1.0 mg) is thought to play a part in the sleep process and is effected by light and dark signals. A few of the minerals considered to aid in glucose management are chromium (200 mg), magnesium (400-600 mg), magnesium citrate, magnesium chloride, vanadyl sulfate (50 mg) and sodium butyrate.
Dr. Bland discussed a few phytonutrients, plant and herb extracts, believed to be of benefit. The Indian spice curcumin is a natural anti-inflammatory and anti-oxidant. Baby aspirin is currently being tested in clinical trials investigating its role in decreasing inflammation. Quercetin, found in garlic and onions, is another natural anti-inflammatory. The recommended dosage is 500mg daily. Garlic also contains ajoene, a pro-apoptotic substance believed to promote programmed cell death. Limonene is a monoterpine found in lemons and limes. This non-toxic extract helps to down-regulate the activity of certain oncogenes. Isoflavones, found in soy, and lignin, found in flax seed meal, are both believed to be protein tyrosine kinase (PTK) inhibitors. The suggested dosages are a controversial subject. Catechin, the substance found in Chinese green tea, is thought to inhibit telomerase activity and ultimately cell division.
III. The Program Presented by Dr. Nixon
A. Background
Dr. Nixon serves as the president of the American Health Foundation. He and his colleagues developed a cancer prevention eating plan called the Risk-Reduction Program. Dr. Nixon discussed some of the epidemiological and clinical evidence to support the nutritional guidelines presented by Dr. Bland. He was in agreement with the majority of the dietary recommendations, with the exception of a few things. Dr. Nixon cautioned patients about DHEA and eicosapentaenoic acid (EPA), and advised women at risk for breast cancer to be wary of selenium, which has been shown to contribute to increases in breast cancer.
The cancer development process is not a fast process. It takes about 30 years for a colon or prostate cell to become cancerous and about 10-15 years for a breast cancer cell to turn malignant. This provides a large window of opportunity for cancer prevention and nutritional intervention. There are three discrete stages of the process. The first stage is the normal cell which progresses to dysplasia and then carcinoma in situ. There are approximately twenty million people with carcinoma in situ, of which about 1.2 million develop cancer each year. The twenty million people are the target group for disease prevention. Depending on the cancer stage, there are different types of nutritional manipulation for treatment or prevention.
Variations in lifestyle across the globe result in higher frequencies of different types of cancer. It is well known that westernized lifestyle is associated with adenocarcinomas, such as colon, prostate and breast cancer. Squamous cell cancers, which include head, neck and esophagus cancers, are more prominent in third world countries. These differences may be partly due to the obese nature and rich lifestyle found in western culture in comparison to the undernourishment of many third world nations. There are also various controllable risk factors in lifestyle that may affect the development of abnormal cells. These factors include smoking, diet and alcohol consumption.
B. Research
Dr. Nixon participated in a series of experiments at Emory University in the 1980s investigating cancer cachexia. In three different studies the investigators were unable to replace lean body mass with traditional feeding. The patients were fed plentiful amounts of varied food, yet tumors continued to grow while the patients lost weight. They found that overfeeding the patients with fat and calories even resulted in a decreased survival rate. In colon cancer specifically, the cohort that was overfed lived only 80 days and the control group survived 360 days. The conclusion was to not force feed patients, rather figure out what is "bad" in food and causing cachexia. The task at hand is to discover and exploit the "good" components of food. Focus was placed on exploiting tumor growth mechanisms. These include processes such as apoptosis, angiogenesis, hormone regulation and energy requirements.
C. Details
Dr. Nixon prescribes a low fat diet in his Risk-Reduction Program. Increased fat in the diet may produce obesity. Obesity results in an increase in the total number of cells, an increase in cell divisions and an increase in abnormal changes. Increased divisions and mutations, in particular, are precursors to the development of malignant cells. Excess fat also results in an undesirable increase of fatty acids. Increased linoleic acid, for example, stimulates growth of breast and prostate cancer cells. A rise in fat metabolism can result in hormone imbalance. Increased fat breakdown can increase estrogen levels in women, thereby increasing tumor stimulus. Finally, including animal fat in the diet may increase the level of carcinogens to which the body is exposed because of supplements or pesticides that the animals themselves ingest. Patients are urged to learn the components of fat and select food containing monounsaturated fats instead of saturated fats.
Phytonutrients are substances contained in all natural plants and herbs. People are encouraged to selectively increase intake of these substances due to their potential benefits to health. Dr. Nixon recommends a daily dosage of strawberries and blueberries because of they contain a substance thought to promote apoptosis. The compound is ellagic acid and is found in strawberries, blueberries, raspberries, grapes and figs. In one trial, cancer patients were fed a cup of fruit per day, which contained approximately 1.460 grams of ellagic acid. Investigators biopsied cervix cells for evaluation. The compound stopped DNA synthesis and mitosis. Apoptosis and an increase in tumor suppressor genes were observed in twenty four hours.
Fiber has received much press lately due to its link to reduced risk of developing heart disease, high blood pressure and colon cancer. Americans need to increase their daily dose of fiber to the recommended 25-40 mg dosage. Dr. Nixon reviewed two trials involving fiber. The first study showed a decreased risk of developing polyps by taking supplements. The second trial concluded that patients with familial polyposis using fiber can prevent colon cancer.
IV. Difficulties
The vast amount of available material is a major difficulty for the cancer patient. The challenge lies in the ability to distinguish between proven fact and speculation and knowing what to incorporate into a personal diet. An additional hurdle may be the adjustments in lifestyle to meet these nutritional needs. Interaction of certain foods or supplements with various types of chemotherapy may be a consideration for some people. The patient, preferably with a physician's guidance, ought to carefully monitor such interactions. Again, each cancer patient has different nutritional needs and therefore should individualize therapies to meet those needs.
V. Comments
Dr. Feldman, representing the American Cancer Society reviewed the data presented and provided his perspectives on nutritional guidelines. Cancer patients, and the population at large need to increase intake of fruits and vegetables. Scientists are continuing to discover important compounds and nutrients in plants that promote favorable physiological processes in the body. Furthermore, data shows that a high fat diet is undesirable and people need to decrease fat intake over their lifetime. Vegetable fat is preferable over meat and dairy fat. Some fat is important such as omega-3, omega-6 and omega-9. However, in reference to Dr. Bland. s diet, some people have benefited from a high fat, high protein diet. The importance of individualizing therapies to meet personal needs is stressed. The higher the dose of a supplement, and the less clinical evidence supporting it, the greater the chance for side effects; consequently potential benefits and risks of a substance must be carefully weighted. A few of the better proven supplements include vitamin E, soy, folate with multi-vitamin, baby aspirin, flax, onion, garlic, curcumin and anti-inflammatories. Shark cartilage, melatonin, N-acetylcysteine (NAC) and beta-carotene have less clinical data to support their efficacy. The bottom line is to consider all recommendations and communicate with physicians. Eating a balanced diet over a life-time is the best way to fight cancer and prevent disease.
A pro-active attitude and willingness to assume responsibility for one's actions are the first steps towards a healthy balanced diet. There are no recipes, nor quick and easy answers for what to eat or not to eat. These speakers provided only the information and advice necessary to make personal decisions. They encouraged patients to communicate with their physicians, as well as other health care providers in areas such as nutrition and alternative medicine. Patients should strive for a 'body in harmony' and possess the knowledge to achieve such balance. Eating a balanced diet, considering all dietary options and monitoring the interaction of food and supplements with chemotherapy were the main points. Listeners are encouraged to further research any food or supplements of interest.
VI. Audience Questions
How does one handle the confusion caused by the labeling and concentrations of over the counter drugs?
Beware! Know recommended doses! Many pharmaceutical companies now ascribe to quality awareness and quality control policies.
How does nutrition therapy relate to chemotherapy in terms of pulsing? (Pulsing refers to coordinating treatment with circadian rhythms in order to achieve maximum benefit.)
There has been some data on circadian rhythms and how chemotherapy and radiation treatment relate to nutrition in the chronobiological sense. For example when the drug should be delivered, over what length of time, etc. Physicians are taking steps to personalize treatments, however there is no concrete evidence to date on the benefits of pulsing.
How much soy should an estrogen positive woman intake?
One-two portions per day of soy is the recommended amount because we do not yet know the implications of taking more. The maximum recommended dose is about 100-150 mg/day. As with all supplements, one should beware of high doses of individual supplements.
Recent studies show a link between colon cancer and fiber, please comment.
(Dr. Nixon) Wheat fiber is thought to be preventive for colon cancer; however, one Harvard group study showed that a high fiber diet did not decrease the chance of developing colon cancer.
Dr. Feldman commented that cereal fiber is better for prevention.
VII. Resources
Health Comm Research Clinic
http://www.healthcomm.comInstitute of Functional Medicine
http://www.fxmed.comWINS trial information (212) 551-2500
American Health Foundation
http://www.ahf.orgCameron E, Bland J, Marcuson R. "Divergent effects of omega-6 and omega-3 fatty acids on mammary tumor development in C3H/Heston mice treated with DMBA." Nutr Res. 1989;9: 383-393.
Bland, Jeffery, Ph.D. "Guest editorial: beta-carotene controversy." J Advancement. Med. 1996; 9 (no. 2): 91-94.
Bland, Jeffery, Ph.D. "Phytonutrition, Phytotherapy, and Phytopharmacology." Alternative Therapies. 1996;2 (no.6): 74-76.
Bland, J and Levin, B. "Nutritional support for a biopsychological approach to cancer therapy." Advances: J. Mind-Body Health. 1997;13 (no.1): 26-30.