Prostate cancer is the most common cancer of men and the third most common cause of death from cancer. Prostate cancer usually occurs in men above the age of 50. Many men who have prostate cancer, do not show any symptoms. Screening for this cancer is usually done by a Digital rectum exam (DRE) and/or Prostate specific antigen test (PSA). Digital rectum exam is the palpation of the prostate through the anus to check the size of the prostate. Prostate specific antigen test is a blood test to check if the prostate is releasing this specific antigen in the blood stream which can be a strong indication of prostate cancer. Research has been done on preventing and reducing the risk of obtaining this cancer. In these studies, nutrition can play a vital role in reducing the chances of getting this cancer. Diets that high in fruits and vegetables, low in fat especially fat from meats are shown to decrease the risk and development of prostate cancer.
Specific food groups have shown in several studies to be a crucial tool in preventing and slowing the progression of this disease. One group of foods that have shown a significant reduction in avoiding prostate cancer is plant based foods. Plant- based foods are shown to contain high amounts of vitamins and elements known to reduce cancer cell. For example, plant- based food contains vitamins and phytochemicals such as carotenoids, flavonoids, phytoestrogens and isothiocyanates (Ma & Chapman, 2009). These phytochemicals have shown to regress cancer cell development and stop tumor promotion. Furthermore plant based diets are high in antioxidant. Antioxidants are molecules that prevent the oxidation of other molecules. Oxidation is the reason behind the production of free radicals. In addition, antioxidants reduce the damage to DNA by binding to these free radicals and eliminating them from the body. Free radicals damage the structure of DNA which can lead to tumor growth. An important carotenoid and phytochemical is lycopene. Lycopene is found in fruits such as tomatoes. Lycopene is known to reduce insulin-like growth factor 1 (IGF-1) signing. IGF-1 is protein that has found to promote prostatic cancer cells and allow the prostate to be susceptible to cancer. Cruciferous vegetables such cauliflower, broccoli, Brussels sprouts and bok choy all contain a compound call glucosinolate. Glucosinolate have shown in studies to reduce DNA damage, induce apoptosis and inhibit prostate cancer cell (Ma & Chapman, 2009).They also possess phenethyl isothiocyanate, sulfophorane and indole-3-carbinol, which are compounds that have potential anti-cancer properties. Their mechanism of action involves the inhibition of cytochrome P450 enzymes, which oxidize compounds such as benzo[a]pyrene and polycyclic aromatic hydrocarbons (PAHs) into more polar epoxy-diols. Cytochrome P450 enzyme is a known agent to cause mutation and cancer growth
Another vegetable that constitutes an impact on tumor cells is soy bean. Soy beans contain isoflavones*. Isoflavones are organic 3-phenylchromen-4-one structure substances that natural occur in different types of foods. They inhibit enzymes associated with transmission of signals for tumor cell growth. `Tea especially green has been found to have similar effects to consuming vegetables and fruits. Polyphenol compounds in green tea have also been found to have the same effects as the cruciferous vegetables. They prevent metastases of the cancer, induce apoptosis and inhibit cell growth. Studies have shown that green tea inhibits tumor growth, therefore, leading to lower prostate-specific antigen levels and lower IGF-1 levels (Ma & Chapman, 2009). One of these polyphenolic compounds is epigallocathechin-3 gallate (EGCG). EGCG is known to attach to urokinase, Urokinase is an enzyme that helps tumor cells grow. In the current market, there is a drug called amiloride and is used Amiloride can only have a maximum dose of 20 mg EGCG while normal cup of green can have upwards of 150mg EGCG. Another benefit is that green tea can be consumed at much higher rate than amiloride and not have physiological effect on the body (Jankun ,1997, p561) .
The next groups of food that have shown to inhibit tumor cell growth are fish oils. Fish oil contains n3 polyunsaturated fatty acids. n3 polyunsaturated fatty acids are known to reduce serum prostate-specific antigen (PSA) protein expression (Ma & Chapman, 2009). PSA is produced by the prostate gland and is used by the body to liquefy semen. The body uses excretes PSA in semen but sometimes in the presence of cancer, the PSA escapes to the blood stream. There two main groups of fatty acids, omega 3 and omega 6 fatty acids. , Omega 3 fatty acids protect from cancer, while omega 6 fatty acids have been found to promote cancer when consumed in excessive amounts. One reason why omega 6 promotes cancer is because of its ability to promotion inflammation. (Tandon et al., 2008).
Another antioxidant that has shown significant effect on prostate cancer cell growth is vitamin E. Vitamin E is considered as an intracellular antioxidant and an antiprostaglandin. * Antiprostaglandins are a group of molecules that reduce the production of mediators of the inflammatory process. As with any fat soluble vitamins, too much can have harmful effect. Intake of over 400 IU can be harmful to the body (Ma & Chapman, 2009). In addition another vitamin that is important in inhibiting tumor cell growth is vitamin D. In studies, vitamin d has shown in both regular cells and cancerous to convert vitamin d into an active hormonal state. In this state, vitamin D has shown to inhibit tumor grow especially prostatic epithelial cells. (Tandon et al., 2008).
Another substance besides vitamins that can help in the fight against is minerals. Minerals differ from vitamins in that vitamins are organic and contain carbon while minerals do not and are consider inorganic. A particular mineral, selenium, has been proven to be a protective agent. It reduces cellular proliferation, causes apoptosis and inhibits angiogenesis. (Ma & Chapman, 2009). Angiogenesis is the growth of new capillary blood vessels in the body. In preventing blood vessel formation; the tumor cannot grow or spread (Li, Smith & Li, 2011).
All the foods discussed above have shown to decrease the instance of prostatic cancer cells. On the other hand, there are groups of food that are now known to promote prostate cancer cells. For example, meats especially cooked at high temperatures contribute to the production of cancer cells. When a meat is cook at high temperature, it releases carcinogens. Carcinogens are known to alter DNA which can lead to two results, apoptosis or promotes uninhibited cell growth. The two carcinogens that are produced during this process are Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). (“Why Carcinogens Cause Cancer”, n.d.). A way to reduce HCA and PAH formation in cooked meats is to reduce the amount of time the meat is cooked on an open flame. This can be done by continuously flipping the meat or using a microwave to shorten the cooking time on the stove.
Another carcinogen that is found in meat is N-nitrosocompound. This carcinogen is found in bacon, hot dogs and anything containing sodium nitrate. Sodium nitrate is preservative added to food to not only preserve but also to add flavor to. N-nitroso is formed when the sodium nitrate combines with the amines in the meat to form this carcinogen. These N-nitroso compound attacks cells and can cause mutation to the molecule’s DNA (Mehdad, 2010).
In another study, there was evidence that a high fat diet contribute to prostate cancer. In this study, men consumer high types of monosaturated and polyunsaturated fats significantly increase their chances of getting prostate cancer (Crowe et al., 2008). Men who were consuming 45 grams of total fat in a day have 10-20 percent increased risk of getting cancer (Park, Murphy, Wilkens, Henderson, & Kolonel, 2007). In another study, there was a strong correlation between obesity and prostate cancer. In a study of eighty-seven men with prostate cancer, 89 percent of these men were overweight or obese. Ninety- seven percent of them had a body fat of twenty five percent or higher (Mehdad, McBride, Grillo, Camilo, & Ravasco, 2010). Obesity increases the body’s production of IGF-1 which discussed early leads to cancer cell proliferation.
As with anything, specific groups of foods need to be taken in moderation. Daily activity and a balanced meal can contribute greatly to not only prevent cancer growth but living a healthy happy life. Prostate cancer is the most common cancer for men and the second leading cause of cancer death in men. Eating foods high in antioxidants, phytochemicals such as vegetables and fruits can lead to the reduction of prostatic cancer cell forming. In addition, avoiding diets high in preserved meats, diary and cooking at high temperature all can additionally reduce men’s chances of getting prostate cancer.
Crowe, F.L., Key, T.J., Appleby, P.N., Travis, R.C., Overvad, K., Jakobsen, M.U., Riboli, E. (2008). Dietary fat intake and risk of prostate cancer in the European Prospective Investigation into Cancer and Nutrition. The American Journal of Clinical Nutrition, 87: 1405-1413.
Li, W., Hutnik, M., Smith, R., & Li, V. (2011). Understanding Angiogenesis. Retrieved from http://www.angio.org/ua.php. April 4, 2014.
Ma, R.W.-L. & Chapman, K. (2009). A systematic review of the effect of diet in prostate cancer prevention and treatment. Journal of Human Nutrition and Dietetics, 22:187-199.
Mehdad, A., McBride, E., Grillo, I.M., Camilo, M., & Ravasco, P. (2010).Nutritional status and eating pattern in prostate cancer patients. Nutricion Hospitalaria,2 (3): 422-427.
Park, S., Murphy, S.P., Wilkens, L.R., Henderson, B.E., & Kolonel, L.N. (2007). Fat and meat intake and prostate cancer risk: the multiethnic cohort study. International Journal of Cancer, 121: 1339-1345. “Prostate Specific Antigen”. Retrieved from http://www.medicinenet.com/ prostate_specific_antigen/article.htm . April 4, 2014.
Tandon, M., Siddique, R.A., Avrind, R., Singh, N.K., Ambwani, T., & Rai, S.N. (2008). Anti-cancer diet: reviewing the role of nutrition in cancer prevention. Current Topics in Nutraceutical Research, 6(2): 67-82. “Why Carcinogens Cause Cancer”. Retrieved from http:// www.edinformatics.com/interactive_molecules/dna.htm. July 10, 2010. World Cancer Research Fund / American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington, DC: AICR, 2007