With a plethora of information available to consumers and billions of dollars devoted to research and medical care, cancer rates continue to rise. According to The National Cancer Institute, by the year 2020, cancer is estimated to reach a $174 billion expense. Breast Cancer is the most common cancer in women with prevalence rates estimated at over 4 million cases by 2020(15). However, 85-90% of breast cancers are not caused by a genetic predisposition, but more often correlated with environmental factors and lifestyle choices (23). Considerable evidence that our lifestyle choices contribute to the incidence of disease or prevention include consistent data supporting the benefits of regular exercise, maintaining our weight, lowering our stress levels, not smoking, and eating a healthy diet (REF). Thousands of studies have included analyses on fats, sugars, carbohydrates, spices, beverages, and every meat, fruit, and vegetable imaginable. More specifically, several epidemiological studies have determined that there is a positive correlation between breast cancer and diets high in saturated fats including the consumption of red meat and dairy products. (Outwater- need REF pr. 1,2). Animal meats and dairy products have been studied extensively due to high content of saturated fat, chemical toxins, contaminants, hormones, and growth factors. Breast cancer has been shown to be strongly correlated (as well as other cancers) with consumption of beef and milk products treated with growth hormones ('Epstein'.) Studies comparing lifestyle and dietary intake show supporting evidence for correlation with the western diet of high fat, meat, and dairy foods including data indicating America has the top incidence breast Cancer while, Japan has a lower incidence and China has the lowest rate(need ref). ***Look for cancer incidence by the WHO)Breast cancers increased in populations with increased dairy intake, but showed even higher increases in cancers correlated with an increase of meat consumption (Outwater.ref-10), 14,15,16 of REF 11). Though a highly controversial debate, strong arguments exist regarding the harm done by additives, antibiotics, and hormones on our health and promoting cancer, primarily estrogen sensitive cancers in women (11).
Firstly, reviewing the roles of natural hormones under normal circumstances begins with natural estrogen. Estrogen is produced in the ovaries and is essential in women for the development of secondary sex characteristics such as breast development, influences in higher pitch voice, skin, shape of the body fat distribution and hips, influence emotions, follicular development, menstrual periods, pregnancy, and contribution to sex drive. Testosterone, also produced in the ovaries in small amounts, is primarily for sex drive and building bone in women. Prior to menopause, estrogen is mainly produced in the ovaries and very small amounts other areas such as the adrenal glands, while after menopause, estrogen is made mostly in the fat cells and adrenal glands and minute amounts in the muscles. Three main hormones produced by the ovaries are estrogen, progesterone (prepares uterine lining for pregnancy), and relaxin (acts on pelvic ligaments during labor).The three main estrogens produced are estradiol, estrone, and estriol. Estradiol is the most abundant type of estrogen and is considered the most potent as it is the one that contributes most to the increased risk of breast cancer (Need Ref) It is produced more during a woman's menstrual period, so the earlier a young women begins her periods, the higher her risk of breast cancer in her lifetime due to more exposure to estradiol. Statistically, if a girl was 10 years old when she started her period, her risk of breast cancer is 30% higher than a girl that started at age 16. Additionally, if a women goes through menopause at age 55, versus early at age 45, her risk of breast cancer is increased by 50% in comparison. The shorter a women's menstrual cycles are, and the more pregnancies she has, both decrease the amount of exposure to estradiol and also decrease the risk of breast cancer. (Need Ref). Estriol goes up during pregnancy, and is a protective form of estrogen which lowers risk of breast cancer (Outwater). Estriol is the weakest of these three natural estrogens; it is actually 1/1000 the strength of estradiol in its ability to initiate cell proliferation. Studies indicate that women who have not had children are somewhere in between 20-70% higher risk of breast cancer and that women that breast feed can even lower their risk even more (need Ref) . Estrone, the least abundant of the 3 natural estrogens and is produced by the ovaries and adipose tissue and is classified as a carcinogen in females (14). Adipose tissue produces excess estrogen which is linked to the development of breast cancer. Progesterone is involved in regulation of the menstrual cycle and needed to maintain pregnancy and balance the effects of estrogen. Additionally, growth hormones play a significant role in the endocrine system. Growth hormones are secreted from the anterior pituitary and are highly regulated by insulin-like-growth factor-1 (IGF-1). The liver produces IGF-1 which mediates a number of functions such as DNA synthesis and cell division, and development and proliferation of many cells in the body (nerves, muscles, organs).
Breast cancer is considered a 'hormonal' disease due to many factors. Elevated endogenous estrogen, androgens, and progesterone are all associated with and increased risk of breast cancer (14). The normal rate of cell division depends on the strength of the estrogen. Excess estrogen can cause increased mitotic division of the breast cells, and the more rapidly cells divide, the more likely a mutation and the increased risk of cancer can arise. Estriol is weaker and slows down cell division, while estradiol is a strong estrogen and speeds up cell division. Under normal conditions, estrogen is broken down in the liver into what may be considered good or bad metabolites. Mechanisms involved in estrogen causing cancer include mutagenic and genotoxic estrogen metabolites and estrogen stimulating tissue growth (14). If the liver has a lot of toxins or chemicals, the estrogen may be routed back to the estrogen receptors and initiate more cell division, increasing the risk of breast cancer. If the estrogen is metabolized properly, it is sent to the colon or the bladder and eliminated from the body. The more estrogen the body is exposed to, the higher the risk of breast cancer: at age 20, the risk is about 1 in 20,000, at age 40, the risk is about 1 in 200, and at age 80 the risk is about 1 in 9 (14, Need Ref 2nd part). Normally estrogen receptors play a role in cell proliferation, and if they are stimulated in error, cancer could develop. Estrogen works efficiently for our bodies when it is balanced, but when it's not balanced it can have deadly effects (24). Additionally, xenoestrogens are foreign, man-made estrogens that have toxic estrogenic effects on the body. Xenoestrogens often found in pesticides, acetones (nail polish), and pollutants are not as easily cleared from the body and tend to accumulate in the tissues (24). Meat products also contain different residues that are potentially genotoxic, immunotoxic, carcinogenic, and endocrine disrupting that cause negative health effects when consumed (20).
Hormonal residues and their metabolites remaining in beef and milk products during consumption causes great concern regarding interference with normal receptor functions impacting growth, tumor formation, and cancer development. Animals are genetically manipulated and given numerous drugs for a number of reasons including preventing or controlling infections and stimulating growth. Research indicates the drug residues could accumulate in the body with repeated consumption over time (18). To guard against potential health issues, the Codex Alimentarius Commission establishes guidelines regarding the application and control of drugs used in food production. Based on toxicological data, a maximum residue limit (MRL) is legally established. The concentration of a chemical residue per kg of food cannot be over legal limits (18). In the US, the United States Department of Agriculture (USDA) Food Safety and Inspection Service monitors compliance of MRLs (10).
Several decades of controversy surround the ongoing battle of allowing the use of hormonal additives in meat and dairy production. Additives are given to increase profits by improving feed efficiency and create higher quality products to sell to consumers. Hormones are given not only to promote growth, but several hundred other substances complicate the issue: antibiotics, beta-adrenoreceptor blocking agents, anti-helminthes, tranquillizers, anti-coccidials, vasodilators, and anesthetics are all used to increase profits by improving the efficiency of production (10). Thus, the following are only a very small portion of hundreds of hormonal products, drugs, and additives involved in the ongoing dispute regarding their effects on the human body.
Most of the drugs are considered orally active substances which means they can be given to the cattle in their food or water. In other cases, hormones are administered through a pellet implant in the ear that releases the hormone slowly. Hundreds of growth promoting substances can be added to the food, water, injected, or implanted and the most common include steroid hormones and a large number of antibiotics to fight infections and prevent the spread of infections between animals. Government regulators have determined withdrawal times of the drugs to lessen the concentration of the drug or its metabolites in the food-the MRL (***REF Reeves 2007). More illegal activity was pointed out by Suzanne LeVert survey in 1986 found that up to half the cattle had the hormone pellets inserted into the muscle tissue and not into the ear. Higher hormone absorption occurs and Dr. Epstein from the The Breast cancer Prevention Coalition reported that the levels of estradiol and other hormones are more than triple that found in controls. Thus increasing breast cancer rates, uterine, prostate, testis . the Hormonal action on the endocrine system disrupts growth . (Ref- Epstein, Steinman , LeVert 194-195). (5).
Products with hormonal activity include testosterone, trenbolone acetate, zeranol, and melengestrol acetate to name only a few. These products or their metabolites that remain in meat, milk, or beef products at consumption are implicated in causing adverse effects on consumer health. Scientists, consumers, and activists against their use are working towards banning their use as occurred with Diethylstilbestrol (DES), which became banned in the 1940's when it was proven to be genotoxic, mutagenic, and carcinogenic (***Lone 1997). Some growth promoters are steroid hormones that exert estrogenic, androgenic, and gestagenic, effects by promoting growth in each of these pathways increasing weight gain and improving the lean meat-to-fat ratio (19).
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