Introduction
Finding a cure for cancer has been an elusive decades long treasure hunt. Within the last twenty years or so; Patrick Quillin, PhD, RD, CNS, author of Beating Cancer with Nutrition, and other research has shed new light on diet playing a role in the prevention and potential reversal of cancer. Nutrition and diet play a substantial role in the development and preservation of the human immune system and overall health of the human body on the cellular level. However, the correlation between diet and cancer is unclear despite research being conducted in the field of nutritional oncology. Though significant progress has been realized in the treatment of cancers through modern technological advances in medicine, prevention and mitigation of cancer lay within nutrition, more specifically a natural diet consisting of fruits and vegetables, which contain antioxidants and phytonutrients.
Background
Cancer is a collective term describing uninhibited cell propagation in various parts of the human body [1]. This process is called carcinogenesis (literally means “cancer creation”). Once propagated, the cancer can spread and cause death in a timely manner. Cancer occurs via mutations in the genetic code that can occur in a variety of cells in the human body. Mutations of this sort are believed to be the result of oxidative stress. In the human body oxidative stress occurs when there is a disparity between free radicals and antioxidants, thus compromising the body’s ability to cleanse itself. In fact, one of the more detrimental characteristics of oxidative stress is the production of free radicals. Finding the cause of cancer in any patient is, for the most part, unfeasible as there are a variety of possible causes for various cancers, but it all begins at the cellular level with the ever-presence of free radicals. Presently, there are many known risk factors for carcinogenesis, but perhaps the most influential risk factors are environmental and poor diet [2]. Consider your diet for just a moment; does it consist of natural fruits and vegetables, lean meat, or fish? Does it consist of french fries, pop, potato chips, and the occasional Subway sandwich? If it consists of processed and fast foods; then the diet is lacking vital nutrients and antioxidants, which promote a state of oxidative stress, and thus the proliferation of free radicals.
Free Radicals, Antioxidants, and Diet
Free radicals are defined as unstable, highly reactive compounds with one unpaired electron that can be neutral, positively, or negatively charged. It is this characteristic that makes free radicals hazardous to health. Free radical reactions occur in three steps: initiation, propagation, and termination. In the first step, free radicals are formed. In the propagation step, the free radical is consumed and produced several times in a cyclic fashion until terminated. In this process the end product of the reaction is the starting material or, in other words, free radical reactions fuel themselves. This process goes on until that one available electron is paired with another compound, in this case the antioxidant, thereby terminating the reaction [3]. Although many free radicals are formed inside the body, according to Davis, the environment presents even more in the way of free radicals in that “environmental pollutants are sources for free radicals including nitrogen dioxide, ozone, cigarette smoke, radiation, halogenated hydrocarbons, heavy metals, and certain pesticides” (297). Oxidation reactions functions normally in the human immune system, but when the toxic byproducts (free radicals) outdo the antioxidant protection mechanisms the resulting state is called oxidative stress.
There has been much excitement in recent years concerning the role of antioxidants in the prevention and even therapy of various types of cancer. An antioxidant is a molecule that effectively inhibits oxidation reactions that produce free radicals, and thus reduces oxidative stress. Patrick Quillin, author of Beating Cancer with Nutrition, explains that natural foods that contain antioxidants can be found in “vegetables, cold water fish, legumes, whole grains, kelp, berries, yogurt, green tea, natural seasonings, and water” (130). Vegetables rich in antioxidants include “beets, spinach, carrots, tomatoes, and squash” (130). These vegetables contain phytochemicals, which are antioxidants. Furthermore, they contain in their pigments “20,000 bioflavonoids and 800 carotenoids, which provide extraordinary antioxidant protection for the human body” (130). Coldwater fish, such as salmon and halibut to name a couple, contain certain types of fatty acids, “which slow down the spreading of cancer, stimulate immune functions, and contain trace minerals from the sea that are not commonly found in foods from our mineral-depleted soil” (131). Another class of antioxidants dubbed “super foods” by Quillin include garlic, carotenoids, cruciferous vegetables, mushrooms, legumes, and a few others (132-34). Garlic and onions are known to stimulate natural protection against tumor cells. “Tarig Abdullah, MD, of Florida found that white blood cells from garlic-fed people were able to kill 139% more tumor cells that white cells from non-garlic eaters” (qtd Quillin 132). In another Chinese study researchers found that “a high intake of garlic and onions cuts the risk for stomach cancer in half” (qtd Quillin 132). Cruciferous vegetables including broccoli and cauliflower are “able to increase the body’s production of glutathione peroxidase, [an important antioxidant]” (133). Furthermore, researchers at Johns Hopkins University “found that lab animals fed cruciferous vegetables and then exposed to the deadly carcinogen aflatoxin, [a toxic compound associated with hepatitis B virus and the development of hepatocellular carcinoma], had a 90% reduction in their cancer rate” (qtd Quillin 133). That is to say that maintaining a balanced natural diet rich in antioxidants can reduce the concentration of free radicals in the human body thereby reducing the damages of oxidative stress and thus preventing the onset of carcinogenesis.
It is fairly evident from past research that antioxidants gained from a natural diet can play a huge role in the upkeep of the human immune system. Joye Willcox argues the same suggesting that diet does in fact play “a vital role in the production of the human antioxidant defense system by providing essential nutrient antioxidants such as vitamin E, C, β-carotene, [and flavenoids]” (279). The protective mechanism in which antioxidants work has been intensely researched over the past ten years with mounting evidence suggesting the positive effects against cancer and many other chronic diseases. Significant protective effects from fruits and vegetables were evident in a 2004 study concerning “the antioxidants β-carotene, vitamin E, vitamin C, and selenium” (Willcox 285). This study was published in the article, “Antioxidants and Prevention of Chronic Disease,” where “out of 21 lung cancer studies, 15 found a significant inverse association with β-carotene while 4 found inconsistent results and 4 found no association” (Willcox 285).
As mentioned earlier, oxidation and free radicals are natural process in the human body that when unchecked can lead to oxidative stress leading to DNA damage. This is where cancer begins. While there are many mechanisms the human body employs in the repair of damaged cells, eating natural foods, such as antioxidant-rich fruits and vegetables, can assist the body in repairing this damage as well as significantly reducing the risk of developing cancer over the long term.
Though significant findings suggest positive outcomes in diet playing a role in cancer prevention and mitigation, many skeptics are led to believe, with the advent of antioxidant dietary supplements, that antioxidants don’t play as big a role as many believe in the prevention and mitigation of cancer. Much of this debate lies within dietary supplements and their effect on the human body. According to P.P. Singh, author of the article, “Reconvene and Reconnect the Antioxidant Hypothesis in Human Health and Disease,” Many doctors and researchers are in agreement that “such [dietary] supplements may do more harm than good” (238). It is evident from reviewing the research that synthesized antioxidant supplements are proving to be more harmful due to the excessive consumption by consumers when they do not need them. Singh comes to a similar conclusion stating that, “most importantly, all the [antioxidants] should be present in proper proportion in the defense network-a problem yet to be resolved because [antioxidants], being cell specific, may discharge their duties only when present at [a] suitable site and in [a] conducive environment” (238). The tests being conducted using antioxidant supplements seem to be clouding the results of other tests using natural antioxidant supplements. If the environment in the human body is not conducive, or when there is sufficient concentration of antioxidants in the body; then, instead of seeing a beneficial effect from these antioxidant supplements, a more detrimental effect is being observed in the laboratory. When all is said and done, one questions remains; as a biological being and the most intelligent, what are we meant to eat?

Conclusion
It is suggested that with the implementation of natural foods in conjunction with the elimination of processed foods in an everyday diet, the prevention or even the cure for cancer can be found. For many years before modern civilization our ancestors, lived off the land and ate from the land in a natural unindustrialized environment. With modern agriculture taking over, consumers are finding less “natural” produce. The hormones, fertilizers, and pesticides used in the production of our fruits, vegetables, and animals have led many to believe that humans are indeed causing cancer amongst themselves. Ultimately, with the dawn of industry in western civilization and later, the discovery of fossil fuels came pollution. Today, the problem of pollution is compounded by the exponential increase in population growth around the world. From this one can infer that there is a positive correlation between population growth, pollution, and frequency of cancer in major population centers of developed countries around the world. German physician Max Gerson stated in the early 1900’s that “the soil and all that grows in it is not something different from us. It must be regarded as our external metabolism which produces the nutrients for our internal metabolism, therefore the soil must be cared for properly, it must not be depleted or poisoned otherwise these changes will result in serious degenerative diseases in animals and humans.”

Notes
1. More information on cancer and carcinogenesis can be found in many medical textbooks as this is considered common medical knowledge. See Davis 297-304; dictionary.webmd.com.
2. Much information presented about environmental and dietary factors and their role in cancer can be found a few textbooks and articles. For more information on the link between cancer and diet and environment see Davis 297-304; Willcox 275-785;
3. Information on free radicals, radical reactions, and mechanisms of their action can be found in organic chemistry textbooks and various medical textbooks. See Davis xix-xxiii, 297-304; Smith 538-563.

Works Cited

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