Nutrition & Cancer Rates

¶ … NUTRITION & CANCER RATES

There are many studies which suggest that nutrition is inextricably linked to cancer rates and many of those studies with their findings will be reviewed during the course of the present study. Reports of how the food industry goes about procuring and processing food for the mass public reveal that never more than before the present time has such inherent danger existed in the food one consumes.

There are a vast many hormones as well as other substances that are ingested by animals prior to their slaughter and as well many fertilizers and poisons are used on crops in order to promote their growth and to kill insects that would destroy the crops. One example of today's food production methods that results in more dangerous products being on the food market than in years gone by is the process of feeding beef-fed cattle grains that are not digested well but that makes them grow faster which results in a higher rate of developing e-coli in the stomachs of these cattle whose meat will be on the market upon their having reached the slaughter house. However, the idea of nutrition being linked to health is not new and this fact has been acknowledged across many millennia of mankind's existence.

Purpose of Study

The purpose of the research contained in this work is writing is to examine the relationship between nutrition and cancer rates. Toward this end this study has chosen as the independent variable that of 'nutrition' and the dependent variable has been identified as cancer rates.

Research Questions

The questions addressed in this research study are those as follows:

(1) What effect does nutrition have on the individual's resilience to cancer?

(2) What foods or supplements are most important in combating cancer?

(3) What is the best method that might be used to disseminate and disperse this critical information to the public?

Significance of Study

The significance of this study is the knowledge that will be added to the already existing base of knowledge in this area of study.

Methodology

The methodology of this study is qualitative in that the study will be conducted through an extensive review of literature found in medical journals and other scientific publications that are peer-reviewed in nature.

Organization of the Study

Part Two of this study will serve to review the literature and will then provide a summary of the literature reviewed. Part Three of this study will report the findings and will provide a discussion of the findings and a conclusion of the study.

EXAMINATION OF RELATIONSHIP BETWEEN NUTRITION & CANCER RATES

PART TWO -- LITERATURE REVIEW

The work of Jemal, et al. (2009) entitled: "Cancer Statistics, 2009" states that according to the National Cancer Institute, Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries and mortality data from the National Center for Health Statistics...a total of 1,479,350 new cancer cases and 562,340 deaths from cancer are projected to occur in the United States in 2009. (p.1)

The work of Kushi, et al. (2006) entitled: "Reducing the Risk of Cancer with Health Food Choices and Physical Activity" states that guidelines are published by the American Cancer Society (ACS) and specifically the 'Nutrition and Physical Activity Guidelines' which are stated to serve as "...a foundation for its communication, policy, and community strategies and ultimately to affect dietary and physical activity patterns among Americans." (p.1)

Kushi et al. (2006) states that for Americans who are users of tobacco, the most important determinants of cancer risk are of the nature that are easily modified and these are stated to be: (1) weight control; (2) dietary choices; and (3) levels of physical activity. (p.1) In fact, it is indicated by research findings that "one-third of the more than 500,000 cancer deaths that occur in the United States each year can be attributed to diet and physical activity habits, including overweight and obesity, while another third is caused by exposure to tobacco products." (Kushi, et al., 2006)

While it is true that the risk of cancer is increased by genetic inheritance and it is also true that genetic mutations in cells causes cancer to develop, the largest part of the variation in the risk of developing cancer "across populations and among individuals is due to factors that are not inherited." (Kushi, et al., 2006, p.1) Kushi, et al. (2006) writes that there are many issues in regards to cancer and nutrition in which "the evidence is not definitive, either because the published results are inconsistent, and/or because the methods of studying nutrition and chronic disease in human populations are still in evolution." (p.1)

The lack of certainty is accredited to "studies that focus on specific nutrients or foods in isolation, thereby oversimplifying the complexity of foods and dietary patterns, the importance of dose, timing had duration of exposure, and the large variations in nutritional status among human populations." (Kushi, et al., 2006, p.1) Noted as specific factors that result in complexity in such studies are those inclusive of a study's failure to "find an effect if the intervention begins too late in life, is too small, or if the follow up I too short for a benefit to appear." (Kushi, et al., 2006, p.1) As well, it cannot be expected that a single trial would have the capacity to provide an answer or resolution to all the questions that are linked to the possible effects of nutrition across the lifespan of the individual.

One example stated by Kushi, et al. (2006) is that "randomized trials of weight loss in relation to cancer risk are severely constrained by the current lack of effective behavioral or pharmacologic approaches to help people lose weight and sustain a healthy weight. The cost and difficulty of randomized trials to determine the long-term consequences of interventions that begin in infancy and extend for many years preclude long-term experimental interventions. Interventions are ethical only if they can plausibly improve the health of the participants. Although it might be easier to motivate people to increase their weight by consuming more calories and/or fat and by decreasing their physical activity, such studies are clearly unethical." (p.1)

Guidelines of the American Cancer Society are stated to be based "on the totality of evidence form all sources, taking into account both the potential health benefits and possible risks from the intervention." (Kushi, et al., 2006, p.1) The American Cancer Society Guidelines for Nutrition and Physical Activity include recommendations for community action and state that factors known to have a strong influence on the choices of the individual concerning diet and physical exercise include the: (1) social; (2) economic; and (3) cultural factors. It is stated that while many individuals would like to adopt a healthier way of living that there are "substantial barriers...that make it difficult to follow diet and activity guidelines." (Kushi, et al., 2006) Current trending towards the increase in the size of portions and high-calorie food consumptions and levels of physical activity which are noted to be on the decline combined with the lack of time needed to prepare healthy meals and all of this results in obesity in the population and this is inclusive of all demographics in terms of age, race, and population segments.

The American Cancer Society reveals that studies conducted in the United States have revealed that "overweight and obesity contribute to 14% to 20% of all cancer-related mortality." (Kushi, et al., 2006, p.1) Studies indicate that being overweight or obese "are clearly associated with increased risk for developing many cancers, including cancers of the breast in post menopausal women, colon, endometrium, adenocarcinoma of the esophagus, and kidney." (Kushi, et al., 2006, p.1) Furthermore, it is related that there is evidence that is "highly suggestive that obesity also increases risk for cancers of the pancreas, gallbladder, thyroid, ovary, and cervix, and for multiple myeloma, Hodgkin lymphoma and aggressive prostrate cancer." (Kushi et al., 2006, p.1) These findings are reported as being supported in "both epidemiologic studies in humans and other research." (p.1)

In 1984, the American Cancer Society Medical and Scientific Committee and its Board of Directors approved a report concerning cancer to be published. This report states that individuals are generally exposed to carcinogens "...20 to 30 years before a statistically significant increase in cancer can be detected. Only then can it be adduced that the increase in cancer may have been caused by exposure to specific carcinogens." (p.121) In fact, it is stated in the 1984 report that there was good reason at that time "to suspect that dietary habits contribute to human cancer..." however, the interpretation of epidemiologic and laboratory data was stated and naturally this still is applicable to be "very complex" and of the nature that it does not allow for conclusions that are clear-cut in nature.

Recommendations stated in 1984 by the American Cancer Society were those listed as follows: (1) Avoid obesity; (2) Cut down on total fat intake; (3) Eat more high fiber foods including whole grain cereals, fruits and vegetables; (4) Include foods that are rich in vitamins A and C. In the daily diet; (5) Include cruciferous vegetables in the diet. (Brussels sprouts, kohlrabi and cauliflower); (6) Consume alcoholic beverages only moderately; and (7) Only moderately consume salt-cured, smoked and nitrate cured foods. (American Cancer Society, 1984, pp. 122-123) What little was understood about nutrition as it relates to cancer rates is summed up in the following specific food categories by the American Cancer Society in its 1984 report:

Food Additives -- chemicals of a variety are added to foods for improving the color and flavor of the foods and to preserve the foods. While some of these have been banned due to having been shown to cause cancer in animals others are believed to protect against carcinogens.

Vitamin E -- Vitamin E is an oxidant and while it may prevent cancer in animals more research is needed of the role Vitamin E plays in preventing cancer in humans.

Selenium -- This substance may be poisonous if wrongly used however, there is evidence that this trace element may provide some protection against the individual developing cancer.

Artificial sweeteners -- there is some evidence that these cause cancer in animals. The long-term risk of developing cancer due to use of the artificial sweeteners has not been fully examined in research.

Coffee -- only inconclusive evidence exist relating to the dangers of coffee.

Meat and Fish Cooked at High Temperatures (Frying, Broiling) - Studies show that this method of cooking meat 'gives rise to a number of potential mutagens (genetic changing agents) in bacteria and that some of these have induced cancer in animals. This is still under investigation (as of 1984).

Cholesterol -- No evidence exists that cholesterol leads to the development of cancer.

The National Cancer Institute reports in its June 11th 2009 publication entitled: "Nutrition in Cancer Care (PDQ) that nutrition plays "major (but not always fully understood) roles in many aspects of cancer development and treatment." (Reeves, et al., 2007, cited in National Cancer Research Institute, 2009, p.1) Malnutrition is stated to be a problem that is a common one among cancer patients and that this issue has been identified as "an important components of adverse outcomes, including increased morbidity and mortality and decreased quality of life. Weight loss has been identified "as an indicator of poor prognosis in cancer patients." (McMahon, Decker, and Ottery, 1998, as cited in National Cancer Institute, 2009, p.1)

It has been shown in research that patients with lung and gastrointestinal cancer at the rates of 60% and 80% respectively, "...have already experienced a significant weight loss, generally defined as at least 10% loss of body weight in 6 months time." (National Cancer Institute, 2009, p.1) Good nutrition assist the patient with cancer maintain their weight and the nutrition stores of the body and this results in "relief from nutrition impact symptoms..." And an improved quality of life. (American Cancer Society, 2000, cited in, p.1)

Nutrition impact symptoms identified by the National Cancer Institute include those of "...anorexia, nausea, vomiting, diarrhea, constipation, stomatitis, mucositis, dysphagia, alterations in taste and smell, pain, depression, and anxiety" all of which may reduce the chances of the cancer patient for survival. It is important that the "eating practices of individuals diagnosed with cancer...be assessed throughout the continuum of care to reflect the changing goals of nutritional therapy." (National Cancer Institute, 2009, p.1) The neoplastic disease progression is stated to often jeopardize the individual's nutritional status and that the changes in nutritional status generally begin at diagnosis "...when psychosocial issues may also adversely affect dietary intake, and proceed through treatment and recovery." (National Cancer Institute, 2009, p.1) Stated as the second most common secondary diagnosis in individuals who have been diagnosed with cancer is that of 'Protein-calorie malnutrition (PCM)' which is known to stem from the failure of intaking carbohydrate, protein and fat in large enough quantities to meet the requirements of metabolism or the absorption of macronutrients reduction. Multiple factors in cancer affect PCM and this is stated to specifically include: "...anorexia, cachexia, and the early satiety sensation frequently experienced by individuals with cancer. These factors range from altered tastes to a physical inability to ingest or digest food, leading to reduced nutrient intake." (National Cancer Institute, 2009, p.1)

Also increasing the incidence of PCM are "...cancer-induced abnormalities in the metabolism of the major nutrients..." (National Cancer Institute, 2009, p.1) These abnormalities are stated include such as "glucose intolerance and insulin resistance, increased lipolysis, and increased whole-body protein turnover. If left untreated, PCM can lead to progressive wasting, weakness, and debilitation as protein synthesis is reduced and lean body mass is lost, possibly leading to death." (Shils, 1999, cited in National Cancer Institute, 2009, p.1)

The subject of vitamins and their potential application in being utilized for prevention of cancer has been a source of debate. The work of Byers (2008) entitled: "Lessons from the Differing Effects of Foods and Supplements" states that study findings show that there was a modest increase in the risk of lung cancer due to the use of vitamin E supplements and that this was particularly true for those who continued to smoke. In fact, it is stated by Byers that each time objective evidence is examined closely "the balance tips away from the benefit (of vitamin supplements in the fight against cancer) and toward harm." (2006, p.1)

Over the past twenty years it is reported in the work of Byers that there has been disappointment after disappointment in the "ability of vitamin supplements to reduce risk for cancers at several sites including the stomach, colorectum, breast and lung." (2006, p.1) While foods rich in vitamins have been linked to reduced cancer development risk study has shown that vitamins when "packaged as pills, clearly do not have the same effect." (Byers, 2006, p.1)

In 2007 The World Cancer Research Fund (WCRF) issued a report that was comprehensive in nature as to the effects that foods and nutrients have upon the risks of developing cancer. This study was based on a systematic review of literature from across the globe and reviewed by 21 experts on cancer risks. The primary conclusions stated in regards to lung cancer were based on 23 case-control studies, 25 cohort studies and three randomized, controlled trails. Findings state that after having controlled for use of tobacco that the group with the lowest intake of fresh fruits were at a 20% increase of risk for developing lung cancer. Findings also claim that beta carotene not only failed to reduce but in face increased the risk of developing lung cancer.

The work of Marshall (2009) entitled: "Nutrition and Colon Cancer Prevention" states that regardless of the improvements in care of colon cancer patients, "...prevention may enable potential patients to avoid cancer therapy. Although screening is direct and effective, dietary modification or low-risk chemopreventive agents might prevent colon cancer development. Epidemiologic findings continue to suggest that diet is related to colon cancer risk. These findings, although, are inconsistent enough to render dietary recommendations premature." (p.1) Nutritional modification is stated to be regarded as "potentially valuable, although research has not yet identified the objects of nutritional intervention." (Marshall, 2009, p.1)

The work of Pala, et al. (2009) entitled: "Meat, eggs, dairy products, and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort" states that the diet of the Western world is linked to a risk of breast cancer. Pala et al. (2009) reports a study in which investigated was "...the relation of meat, egg, and dairy product consumption with breast cancer risk using data from the European Prospective Investigation into Cancer." (p.1) Reported is a study between 1992 and 2003 in which information on diet was collected from 319,826 women." (Pala, et al., 2009, p.1) Pala et al. reports "Disease hazard ratios were estimated with multivariate Cox proportional hazard models."

The study results state that "no consistent association was found between breast cancer risk and the consumption of any of the food groups under study analyzed by both categorical and continuous exposure variable models. High processed meat consumption was associated with a modest increase in breast cancer risk in the categorical model (hazard ratio: 1.10; 95% CI: 1.00, 1.20; highest compared with lowest quintile: P. For trend = 0.07). Subgroup analyses suggested an association with butter consumption, limited to premenopausal women (hazard ratio: 1.28; 95% CI: 1.06, 1.53; highest compared with lowest quintile: P. For trend = 0.21). Between-country heterogeneity was found for red meat (Q statistic = 18.03; P = 0.05) and was significantly explained (P = 0.023) by the proportion of meat cooked at high temperature." (Pala, et al., 2009, p.1) The study reported by Pala et al. concludes the failure to consistently identify intakes of meats, eggs, or dairy products as risk factors for breast cancer." (2006, p.1)