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by Christine Cox One in three Americans will, at some point in their lives, be told they have cancer. This translates into one million cancer diagnoses and 540,000 cancer deaths in the U.S. each year. These are frightening statistics, yet the top cancer experts state that through changing our habits we can reduce our chances of getting cancer by half, and that at least 35%and perhaps a great deal more of all cancers may be prevented by adjusting the way we eat. WHAT IS CANCER?In order to understand how what we eat can affect our chances of cancer, it is helpful to understand what cancer is and how it develops. Cancer is a disease that can affect many different body parts. But no matter which body part is affected, cancer always involves cells that, due to various causes, go through genetic changes such that they start to proliferate wildly. In most forms of cancer the expanding masses of cells form tumors that eventually push against and invade neighboring tissue, disrupting body systems. In the course of time they may metastasize, travel via the blood or lymph to another part of the body where they set up new colonies that in turn grow and invade tissue. How do cancer cells turn into uncontrolled breeding machines? All cells, including cancer cells, reproduce themselves by division, passing on their genetic coding to the new, daughter cells. Healthy cells do this in a controlled manner, dying and regenerating in a socially responsible manner. The rate of reproduction is ordered by an intricate interplay of genetic material located in the center of each cell. Various causes, most notably certain carcinogens, can initiate changes in the genes that regulate the rate of cell division. Scientists have recently discovered that cells contain certain genes which when they get "switched on" become onco-genes. That is, they become genes that can begin the transformation of that cell into a cancer cell. Fortunately, there are other genes called tumor suppressor genes that function to control abnormal growth. If either type of gene becomes damaged, cancerous changes may be initiated. Cells can often repair mutated genes, but sometimes repair does not occur before the cell divides, thus fixing in place the genetic damage. Fortunately, these cells alone do not cause cancer; a cell with damaged genetic material can sit dormant for years. In order to lead to cancer, something must come in to promote the disease. However, at any stage of development, the immune system can recognize these damaged cells as foreign, and destroy them. Cancer promoters include a wide variety of factors, especially inappropriate nutrient intakes, such as those caused by consuming foods of animal origin. Cancer is a multi-stage process that may take years to unfold. Sometimes, even after cancer has developed, 25 or more years may pass before symptoms appear! Since what we eat affects every cell in our body, by changing our diets we have the opportunity to intervene at a cellular level at every meal. Many studies show that a wide variety of nutrients and other substances in plants are capable of fighting cancer at many stages of its development.
The Role of Diet in CancerSince the development of cancer occurs in stages, different nutrients can encourage its advancement, while others can inhibit it at various points in its course. Certain foods and food components can work to foster cancer: INITIATING CANCER
PROMOTING CANCER
FOOD COMPONENTS CAN PREVENT CANCER BY:
Fighting Cancer With Food Fruits, vegetables, and grains in general are anti-cancer champions. Virtually all of them are rich in antioxidants and other substances that block cancer at many stages of its development. The plant foods listed below are a few that appear to be great allies in our fight against cancer. Green tea inhibits tumors of the esophagus, breast, skin, colon and liver in rodents. Soybeans are rich in genistein, a phytochemical that appears to prevent small tumors from growing. Genistein apparently interferes with cancer at many points, from controlling cell proliferation to inhibiting angiogenesis, the building of blood vessels that supply nutrients to tumors. Studies have shown it particularly to protect against breast cancer. Broccoli and the cabbage family are full of phytochemicals that fight cancer. One of them, sulforaphane, protects lab animals from breast cancer. It appears to help cancer-fighting enzymes force carcinogens out of cells. And another, phenmethyl isothiocyanate, apparently disarms carcinogens and prevents DNA from damage. Tomatoes are associated with lower rates of several cancers, most particularly lung and prostate cancer. Flavonoids, phytochemicals that give color to fruits and vegetables, may block the ability of cancer-causing hormones to attach to cells. Garlic and onions contain phytochemicals that activate enzymes that neutralize carcinogens. Flax seeds contain lignans that may block cancerous changes. In addition their oil is rich in omega-3 fatty acids which may be helpful against a variety of cancers. Brazil nuts are rich in selenium, a mineral that, in population studies, is associated with decreased incidence of cancer. Just one of these crunchy nuts a day is enough! They are so rich in selenium that eating too many could give you an overdose. Selenium may block both tumor initiation and promotion. The Anti-cancer diet
Dietary Prevention of Specific CancersBREAST CANCER Almost one in seven American women will get breast cancer. These are frightening statistics, but it turns out that there is quite a lot we can do to keep this common cancer at bay. The cabbage family including broccoli, cauliflower, kale and collards, is rich in an array of anti-cancer phytochemicals. Some of them, called indoles, prompt the body to make benign forms of estrogen that don't promote breast cancer. Soy foods, such as tofu and miso, also appear to be helpful against breast cancer through a variety of mechanisms. Study after study has demonstrated that women eating high-soy diets have lower rates of this disease. Soy is high in a phytochemical called genistein, which has enough biochemical similarity to estrogen that it can slip, like a key into a keyhole, into estrogen receptors in the breast, locking out the "bad" estrogen. Since most types of breast cancer cells are stimulated by estrogen, a diet that includes soy is a good idea for most women. Citrus fruits may be yet another protector against breast cancer. In an animal trial, limonene, a phytochemical found in citrus fruits, effectively warded off breast cancer. Although limonene has not yet been studied in women, why not add a juicy orange or grapefruit to your diet, since citrus is high in vitamin C and other health-giving nutrients? COLORECTAL CANCER If you don't already eat garlic, consider adding this pungent spice to your diet. In a study of 41,000 women, those who ate garlic at least once a week reduced their chances of getting colon cancer by 35%. Garlic has a long folk history as an immune system stimulant that is now being corroborated by modern research. Another culinary additive (the spice turmeric) turns out to be an ally against intestinal cancer. Curcumin, the component of turmeric that gives it its deep yellow hue, appears to protect the intestinal tract from a number of tumor-promoting carcinogens. It might be well to add our spices to a plate of whole grains and vegetables, both of which are high in fiber. Fiber appears to bind carcinogens and move them rapidly through and out the intestinal tract before they can do harm. And because it increases bulk, it dilutes the concentrations of carcinogens against the mucosal lining. But perhaps the most important thing we can do to protect our intestines is to reduce the amount of fat in our diets. Many animal studies demonstrate that high-fat diets promote colorectal tumors, while population studies indicate that people who move from countries with low-fat diets to countries with high-fat diets rapidly increase their chances of getting intestinal cancers. FAT AND COLON CANCER How does fat work to promote colon cancer? Scientists speculate that:
SKIN CANCER Skin cancer is the most common kind of cancer. Fortunately, most forms of it are usually not deadly. However, the rates of a highly virulent form, malignant melanoma, are rising alarmingly worldwide. In the U.S., melanoma rates have increased 500% between 1950 and 1985. Researchers speculate that soaring rates may be due to the thinning of the ozone layer, and to ideals of beauty that include a deep tan. Dr. Safai, for many years chief of dermatology at Memorial Sloan Kettering Cancer Center, suggests that a diet high in antioxidants may protect against skin cancer. The American Journal of Epidemiology reports that melanoma patients had significantly lower blood levels of vitamin E and beta carotene than did people without this skin cancer. A diet high in whole grains and fruits and vegetables will amply provide these valuable antioxidants. In addition, a low-fat diet appears to help protect against skin cancer, according to recent research. Green tea might be a good bet, as well. Mice that drank only green tea got an astonishing 88-93% fewer skin cancers, when irradiated with ultraviolet B rays, than a control group that drank only water. PROSTATE CANCER As many as one in five men will get prostate cancer at some point in their lives. Fortunately, there are many dietary adjustments we can make to help avoid this all-too-frequent cancer. High-fat diets, for one, have been implicated in prostate cancer. A study tracking the eating habits of 48,000 men found a powerful correlation between packing away the grease and the advanced form of this disease. Those men who ate the most fat had an astonishing 79% greater risk of getting advanced prostate cancer than did those eating the lowest amounts. The worst foods? Red meat, mayo, and butter. One of our strongest allies against prostate cancer is the tomato, a component of so many of America's favorite dishes. Eating a lot of tomato products, which are rich in lycopene, a carotene has strongly been associated with reduced risk for this cancer. For those who don't care for tomatoes, watermelon and pink grapefruit are alternate and delicious sources of lycopene. LUNG CANCER Don't let the publicity about the failure of beta-carotene supplements to protect against lung cancer discourage you from following a diet rich in beta carotene. Several studies have shown that high carotenoid diets, as opposed to supplements, do in fact have a protective effect against many cancers, including lung cancer. In fact, even in the study that examined the effect of beta-carotene supplements, those participants who had high blood levels of beta carotene before the study indicating a dietary source of this antioxidant went on to have fewer cases of lung cancer. Why does diet work, while supplements of beta carotene do not? Although they don't know for certain, scientists believe that phytochemicals, natural plant chemicals such as beta carotene, may work through a complex web of interrelations with other phytochemicals that occur naturally with them. In other words, eating a whole food gives you the whole "formula." An additional possibility is that diets rich in beta carotene tend to be diets rich in fruits and vegetables. It might be one or many of the other phyto-chemicals in a high-beta-carotene diet that is our true ally against lung cancer. A recent study found that vegetable consumption had a strong protective effect against lung cancer while milk consumption was associated with a dose- response-related increase in risk. The bottom line? Follow a plant-rich diet. Cancer Treatment and Diet We know that a plant-based diet may help us avoid many forms of cancer, but what about those who already have this disease? Because at least 50% of cancer patients are subject to weight loss, they may have a higher need than usual for calories and protein. To make things more difficult, many types of treatment for cancer can induce a variety of effects that make eating even an ordinary amount of food a challenge. Common Gastrointestinal Side-effects from Radiation and Chemotherapy
Chemotherapy, for example, works by attacking and killing the rapidly dividing cells that are the hallmark of cancer. Unfortunately, other parts of our body, including the bone marrow, hair follicles and gastrointestinal tract, also have rapidly growing cells. Since the chemotherapeutic drugs do not discriminate, they attack these healthy cells as well. Sometimes the resulting gastrointestinal disruption can be quite severe. Radiation therapy also commonly causes nausea and vomiting. All of these symptoms can make it difficult to eat enough for normal nutritional needs, let alone for the requirements of cancer. One of the more peculiar of these symptoms is distortion of taste. Sweet, bitter, and strongly flavored foods may taste strange, metallic, or inexplicably unpleasant. Meats, even in previously avid meat-eaters, are often rejected for this reason. Dairy products (milk and cheeses) can be problematical for other reasons. The intestinal disruption may interfere with the lactase enzyme that is needed to break down lactose, the natural sugar in dairy products. The result can be bloating, gas, and increased diarrhea. WHAT'S GOOD TO EAT? In general, the same diet that is associated with preventing cancer is recommended for cancer patients. Since an anti-cancer diet, one low in fats and animal foods, and high in a variety of grains and vegetables puts less stress on the system while providing an array of immunity-enhancing nutrients, it's wise to eat this way as much as possible. If, due to nausea or other reasons, only small amounts of food can be tolerated, it becomes even more important that the food that is eaten be of the highest quality. Shakes made of a mix of bananas with a half-cup of soy milk can be made quickly and easily in a food processor or blender. Throw a few strawberries or a peach into the mix for a nutritious and truly delicious snack. Beans and lentils, in soup or tacos, make an easy, high-protein meal. Soy products (tofu and soy milk) not only provide protein but also may inhibit angiogenesis, the ability of tumors to build the blood supply they need in order to grow. A series of fascinating experiments showed that the growth of tumors in mice was accelerated when the rodents were fed animal protein, but tumor growth was stopped completely when soy protein was substituted for animal protein. NUTRIENT BOOSTERS FOR CHEMOTHERAPY AND RADIATION Several intriguing studies have indicated that certain nutrients may partially protect normal cells from some of the side-effects of chemotherapy and radiation. Studies indicate that diets high in beta carotene may reduce the incidence of the painfully sore mouth that often accompanies radiation, while those rich in vitamin E may help protect the immune system from chemotherapy-induced damage. Other studies show that some nutrients may enhance the cancer-killing effects of radiation and certain chemotherapeutic agents. Vitamin E-rich diets, for example, appear to enhance the ability of many chemo-therapeutic agents to kill a variety of tumor cells. While these are preliminary studies, cancer patients could do well to make sure they are getting enough deeply colored orange and green vegetables, rich in beta carotene, and whole grains and fresh nuts, rich in vitamin E. Because these nutrients, due to their antioxidant as well as other capabilities, are associated with lower rates of cancer in general, they may help prevent recurrence of cancer as well. Mind/Cancer Connection "Deep anxiety, deferred hope and disappointment are quickly followed by the growth and increase of cancer"Sir James Paget, physician to Queen Victoria, 1870 Sir James may or may not be right, but many physicians, going at least as far back as Galen in the second century, have believed that the state of mind of their patients influenced the incidence and outcomes of their diseases. Today, there is a great deal of interest in this topic and many views on how much, and through what mechanism, the mind influences the body. Virtually everyone agrees, however, that emotional states do in fact affect our bodies to some degree. Just think of the pounding of the heart after a shock, or stomach "butterflies" before a test! In the past decade, scientists have been able to go far beyond the assertions of Paget and Galen, by actually mapping the physiological mechanisms through which the workings of the mind translate themselves into bodily states. There is no doubt that emotional states can affect our endocrine and nervous systems as well as the functioning of our immune systems. Given the mind/body connection, the question when it comes to cancer is: Can our emotional states cause cancer, and can they cure it or slow its progression once it's established? DO EMOTIONS CAUSE CANCER? Most researchers believe that our emotional states cannot cause cancer. But there is a growing body of evidence that, if the biochemical stage has already been set for cancer, that is, if muta-genic cellular changes already exist, then our emotions may further the progression into an active cancer. STRESS AND CANCER As far back as the 60s, a Stanford researcher showed that among a group of rats with implanted tumors, the tumors of those who were stressed by receiving shocks and by overcrowding grew faster than those of the non-stressed rats. Another researcher found that 77% of interviewed cancer patients had suffered the loss of a spouse, child, or other close relationship before the onset of cancer. And study after study has confirmed the fact that stress is associated with dysfunctions of the immune system, our chief defense against cancer. Of course, what constitutes stress is highly individual. What may be stressful for one person may be seen as a hard but rewarding challenge by another. But whatever our triggers, stress cannot be completely avoided in life. Thus, it's a good idea to develop strategies for getting through stressful times. For many people, daily exercise works to dissipate tension. Beyond that, yoga and meditation THE LOVE CONNECTION: SUPPORT AND CANCER Having relationships that give emotional support appears to be a strong key in surviving cancer. Studies in many countries show that cancer patients who have social supports have a lower mortality rate than others with the same stage of cancer who don't have caring relationships. And the relationship doesn't need to be with a "significant other." Patients enrolled in cancer support groups reap the same benefits.
Making Anti-Cancer Nutrition Work For You Here are some simple suggestions for increasing the cancer-fighting power of your diet throughout the day. BREAKFAST
MID-MORNING
LUNCH
MID-AFTERNOON
EVENING MEAL
LATE-NIGHT SNACK
Courtesy of www.nutritionadvocate.com Return From Cancer And Diet To Healthy Diet Copyright 2005-2008 ezHealthyDiet.com
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