Tuesday 6 August 2013

The causes of breast cancer


Till date, scientists and doctors have not determined the exact cause of breast cancer. Nevertheless, experts and researchers are unanimous that, there are a number of factors which can increase the risk of a woman getting breast cancer. These hazardous conditions that can fuel the possibility of a woman getting breast cancer are called risk factors. Nonetheless, from collated evidence provided by numerous research programs around the world, there is a strong link between the dietary products we offer to our bodies and breast cancer. These products may include the type of food and beverages we consumer, whether or not we consume alcohol, smoke, use drugs, etc. The following are some of the most significant breast cancer risk factors; as determined by renowned breast cancer research institutions around the world.
Meat consumption and other animal products
Most people are familiar with the adage that you are what you eat. The veracity of this adage is as solid today as it was millions of years ago. The physical body is made up of a multitude of tiny cells. The body produces new cells regularly. These cells go through the process of birth, maturity and then old age. These aged or worn out cells must be replaced by new cells. The food we consume, especially protein, is broken down and ultimately become the cells of the body. In their book titled: Poison in your body, Steven Null et. al. stated: The animals are kept alive and fattened by continuous administration of tranquilisers, hormones, antibiotics and 2,700 other drugs. The process starts even before birth and continues long after death. Although these drugs will still be in the meat when you eat it, the law does not require that they be listed on the package. When we consume meat and other animal products containing such a frightfully high level of dangerous chemicals, they form intoxicants in our system. Intoxicant briefly means poison. Therefore, these toxic products quickly ruin our health and disable our system. They mutate the normal physiological processes in the body; and precipitate numerous diseases, including breast cancer. To artificially preserve the freshness of meat products, they are usually administered with nitrates, which have been established to be cancerous.
A diet high in animal fat, especially the carcinogens found in cooked red meat, and the fat-soluble hormones found in milk from cows, enormously intoxicates the system. According to Arthur Upton, former Director of The National Cancer Institute in the USA, both breast cancer and colon cancer have been generally associated with the level of consumption of animal fat.
According to fresh compelling data from the European Prospective Investigation into Cancer and Nutrition (EPIC) study, participants who ate the most red meat and processed meat increased their risk of dying by 14 and 44 percent respectively; compared with those who ate the least. Also, The National Cancer Institute in the USA found that women who consumed one or more servings of high-fat dairy products per day, were at a 49% increased risk of dying from breast cancer. Therefore, there is a positive correlation between the consumption of animal products and getting breast cancer. A Harvard Medical School study of more than 90,000 women revealed that the women who ate the most meat were nearly twice as likely to develop breast cancer as those who did not eat much meat. 
Saturated fats and breast cancer
The consumption of a high fat diet also leads to the accumulation of excess cholesterol in the body. Sources of saturated fats in the body include meat products; among them, sausages and pies, butter, ghee, lard, diary products such as cheese, cream, sour cream, ice cream, chocolate products, cakes, biscuits, pastries, eggs, animal fats etc.
An overview study (meta analysis) of 45 studies reported that women who consumed a fat-rich diet had an increased risk of breast cancer. The European Prospective Investigation into Cancer and Nutrition (EPIC study) has demonstrated that women who ate higher levels of saturated fats were twice at higher risk of developing breast cancer, compared to those eating the least. Saturated fats also have the tendency to induce weight gain and obesity, which are both positively correlated to increased risk of breast cancer. Omega-6 fats can increase the risk of breast cancer, while omega-3 fatty acids are known to lessen the growth of breast cancer cells.  Sources of omega-3 fatty acids include flaxseed oil and beans such as kidney, great northern, navy, and soybeans.
Tobacco and Breast Cancer
Tobacco contains a highly poisonous substance called nicotine, together with a large number of other poisonous substances, which are best at nothing else than ruining our health.
According to Cancer Research UK, tobacco smoke contains more than 70 different cancer-causing substances. When you inhale smoke, these chemicals enter your lungs and spread around the rest of your body. Research has further revealed that these chemicals can enter and damage the DNA and mutate important genes. This scenario prompts a perpetual and uncontrollable growth and multiplication of the cells, hence causing not only breast cancer, but a multitude of other forms of cancer. When inhaled, these poisonous substances rapidly infiltrate the blood vessels and are speedily transported all over the body. According to the World Health Organisation (WHO), tobacco use is the single greatest avoidable risk factor for cancer mortality worldwide, causing an estimated 22% of cancer deaths per year. In 2004, 1.6 million of the 7.4 million cancer deaths were due to tobacco use. Tobacco smoking causes various types of cancer, including lung cancer, oesophagus cancer, larynx cancer (voice box), mouth, throat, kidney, bladder, pancreas, stomach and cervix cancers. Therefore, women who smoke have a higher risk of getting breast cancer than their non-smoking counterparts.
Alcohol and Breast Cancer
Alcohol consumption is the most well established dietary risk factor for breast cancer. The Harvard Nurses' Health study, in conjunction with numerous others, have demonstrated that consuming more than one alcoholic beverage a day can increase breast cancer risk by as much as 20-25%. Alcohol includes beer, wine, whisky, gins etc. According to the World Health Organisation (WHO), other types of cancer caused by alcohol consumption include oral cavity, pharynx, larynx, oesophagus, liver, and colorectum cancers. One very crucial study that clearly demonstrated that alcohol consumption substantially increases the risk of breast cancer is the Million Woman Study, conducted by Oxford University in the United Kingdom. The report revealed that every 10 grams above a unit of alcohol consumed, increases a woman’s risk of getting breast cancer by 6%.
When consumed, alcohol breaks down into a substance called acetaldehyde, which can cause genetic mutations. This amounts to a permanent change in the DNA sequence that makes up genes. This can elicit a response from the body, resulting in the development of cancerous cells.
Alcohol is also thought to increase the production of the female hormone oestrogen in pre-menopausal and post-menopausal women. A key feature of a cancer cell is its ability to grow and multiply uncontrollably. In certain types of breast cancer, high circulating levels of oestrogen can trigger the uncontrollable growth and multiplication of cancer cells in the breast. Alcohol can also alter the immune system and contribute to nutritional deficiencies, including folic acid, vitamins A, B6, D and E and zinc, all of which make it harder for the body to fight cancerous cells.
Obesity and breast cancer
Obesity is a condition whereby an individual has an abnormally high and unhealthy proportion of body fat. Researchers measure obesity using a scale known as body mass index (BMI). BMI is calculated by dividing the square of a person’s weight (in kilograms) by the square of their height (in metres). BMI provides a more reliable measure of obesity or being overweight.
In 2008, the World Health Organisation (WHO) stated that approximately 1.4 billion adults worldwide are overweight. In the year 2000, it came to light that the number of worldwide overweight adults exceeded the number of underweight adults. This development was rather unprecedented; and provided a clear indication that obesity is on an upward trend.
Reports from both the International Agency for Research on Cancer and the World Cancer Research Fund revealed persuasive evidence that being obese or overweight causes breast cancer after menopause. Also, in 2006, a study from the American Cancer Society (Cancer Prevention Study-II) discovered that gaining weight as an adult was an even more significant risk factor than current weight for post-menopausal breast cancer. The study found that women who gained 60 or more pounds after the age 18 had doubled the risk of being diagnosed with post-menopausal breast cancer; compared to women who maintained their weight over the same time period. Other studies have reported similar findings.
The increased risk of post-menopausal breast cancer is considered to be due to increased levels of oestrogen in obese women. After menopause, when the ovaries stop producing hormones, fat tissue becomes the most significant source of oestrogen. Considering that obese women have more fat tissue, their oestrogen levels are higher, potentially leading to more rapid growth of oestrogen-responsive breast tumours.
Inactivity (Lack of Excerise) and Breast Cancer

Scientists have discovered that there is a strong link between lack of exercise and increased risk of breast cancer. Cancer Research UK undertook a study in which it was found that more that 3000 cancers each year are positively correlated to lack of exercise. Also, a 2011 study revealed that 3-4% of all bowel, breast and womb cancers in the UK are connected to lack of physical exercise.

Lack of physical exercise may result in blood sugar accumulation, which fuels blood levels of insulin factor, a hormone that affects how breast cells grow and behave.  Lack of exercise can also result in the accumulation of body fat, which in turn increases the probability of being obese. People who exercise regularly tend to be healthier and are more likely to maintain a healthy weight and have little or no excess fat, compared to people who don't exercise.
Age
Studies have established that age is positively correlated to breast cancer; and therefore the older a woman gets, the greater her risk of getting breast cancer. This assertion is strongly vivid in that over 80% of women diagnosed with breast cancer are above 50 years old. Such women are also in their post-menopausal period.
Genetic connections
If a woman’s close relative has had breast or ovarian cancer, then the risk of that woman developing breast cancer is relatively much higher than women without such a connection. Nonetheless, this does not necessarily imply that a woman will at all cost develop breast cancer, if a close relative of hers have already suffered from the disease. It just means that the woman’s probability of developing breast cancer is somewhat higher. Women who carry the BRCA1 and BRCA2 genes have a considerably higher risk of developing breast and ovarian cancers. These genes can be inherited. TP53, another gene, is also linked to greater breast cancer risk.

A history of breast cancer
A woman who has already suffered from breast cancer at some point in her life is more likely to suffer from the disease again, compared to women who have never been plagued by the disease. 
Benign breast lumps
Women who have had some types of benign (non-cancerous) breast lumps are more likely to subsequently develop breast cancer. Examples of such breast cancers include ductal hyperplasia or lobular carcinoma in situ.
Oestrogen exposure
Women who had earlier than normal menstrual experiences or entered menopause later than usual, are more prone to developing breast cancer. Such woman are usually exposed to oestrogen for a longer duration. Oestrogen production commences when menstrual experiences start and stops during menopause.
Higher levels of endogenous hormones have long been conceived to increase breast cancer risk. Studies demonstrate that post-menopausal women with the highest levels of oestrogen and testosterone are about thrice more likely to develop breast cancer. Higher levels of the hormone prolactin have been associated with an increased risk of breast cancer; particularly oestrogen-receptor-positive tumours. Having higher levels of insulin has been associated with an increased risk of post-menopausal breast cancer in women not taking hormone replacement therapy. A link between high insulin levels and breast cancer might explain the 20% increased risk of breast cancer for women with diabetes shown in a meta-analysis. Insulin-like growth factor 1 is positively associated with breast cancer risk.
Radiation exposure
Women who have undergone x-rays and CT scans may have a higher risk of developing breast cancer. Scientists at the Memorial Sloan-Kettering Cancer Centre found that women who had been treated with chest radiation for a childhood cancer have a higher risk of developing breast cancer. 
Cosmetic implants
Women who develop breast cancer, having undergone cosmetic implants; may have a higher risk of dying from the disease, compared to women who have not had breast implants. This was reported in the 2013 May issue of the British Medical Journal. The team examined peer reviewed articles of observations which had been carried out in Europe, USA and Canada. Cosmetic breast implants produce shadows on mammograms and thus render it difficult to spot tumours at an earlier stage. The report further determined that a woman with cosmetic implants has a 25% risk of being diagnosed with breast cancer when the disease has already reached an advanced stage. Women with cosmetic breast implants who are diagnosed with breast cancer have a 38% higher risk of dying from the disease, compared to other patients diagnosed with the same disease who have no implants; concluded the research.
Being childless or having children later in life
Women who do not have a biological child, or who have had a first child after the age of 30, bear a slightly higher risk of developing breast cancer. Being pregnant several times at an early age diminishes the risk of breast cancer. The younger a woman is when she commences childbearing, the lower her risk of developing breast cancer. There is evidence that the reduction in the risk of breast cancer with childbirth, and the increase risk with later age first time birth, may be limited to oestrogen-receptor-positive tumours. Childbearing reduces the risk of breast cancer; and the higher the number of full-term pregnancies, the greater the protection. The risk of breast cancer reduces by 7% with each full-term pregnancy. Thus, overall, women who have had children have a 30% lower risk of breast cancer than nulliparous women. Also, there is a 15% risk reduction for women with a twin birth, compared to women giving birth to a singleton.
Recent use of birth control pills
Research has uncovered that women who are using birth control pills have a slightly higher risk of developing breast cancer. This risk appears to subside once the act of taking the pills is terminated. Women who stopped using the pills ten years ago do not appear to have any risk associated with them. Depot-medroxyprogesterone acetate (DMPA) or Depo-Provera, is an injectable form of progesterone that is given once every three months, as a birth control procedure. Women now using DMPA seem to have an increased risk of breast cancer; but the risk doesn’t appear to be increased if usage of this drug was stopped more than 5 years ago.

Using hormone therapy after menopause
Post-menopausal hormone therapy (PHT) has been used for many years, to help relieve symptoms of menopause and to prevent the thinning of bones (osteoporosis). This treatment has other names, such as hormone replacement therapy (HRT), and menopausal hormone therapy (MHT). Women using these products have been found to have a slightly higher risk of breast cancer. 
Not breastfeeding
Some studies have shown that breastfeeding slightly lowers the risk of breast cancer, especially if the breastfeeding lasts for 18 to 24 months. This could be because just like pregnancy, breastfeeding lowers a woman’s total number of menstrual periods.
Women who breastfeed reduce their risk of breast cancer, compared with women who do not breastfeed. The longer a woman breastfeeds, the greater the protection. Generally, risk is reduced by 4% for every 12 months of breastfeeding.
Women currently taking HRT have a 66% increased risk of breast cancer, compared to those not undergoing the procedure.  The risk increase is temporary, and within 5 years, it subsides to that of someone who has never used it. A woman's BMI modifies the effect of HRT, with a stronger effect in women with a lower BMI. The risk is larger for use of oestrogen-progestagen therapy, compared to oestrogen-only.
A study published in December 2011 estimated that in 2010, just over 3% of breast cancers in women in the UK (around 1,530 cases), were linked to HRT use. According to an earlier study, three-quarters of these additional breast cancer cases are linked to the use of oestrogen-progestagen HRT.
Treatment with DES
In the past, some pregnant women were given the drug DES (diethylstilbestrol) because it was thought to lower their chances of losing the baby (miscarriage). Studies have shown that these women have a slightly increased risk of getting breast cancer. 
Dense breast tissue
Dense breast tissue entails breast with more gland tissue and less fatty tissue. Women with denser breast tissue have a higher risk of breast cancer. Dense breast tissue can also make it harder for doctors to spot problems on mammograms.
Certain jobs
Canadian researchers uncovered that certain jobs, most especially those that put the human body in contact with possible carcinogens and endocrine disruptors, are more likely to increase the risk of a woman developing breast cancer. Such jobs include gambling, bar work, automotive plastics manufacturing, metal-working, food canning and agriculture. They reported their findings in the November 2012 issue of a journal called Environmental Health. French researchers found that women who worked at night prior to a first pregnancy had a higher risk of developing breast cancer.
There is some evidence to suggest that women who do night shift work have an increased risk of breast cancer; while other studies reveal that sleeping longer reduces the risk of breast cancer. One theory purports that disrupted or shorter duration of sleep leads to reduced levels of the hormone melatonin, which has been proven to have anti-carcinogenic properties. Melatonin also suppresses the production of other hormones that have been linked to an increased risk of breast cancer. A recent study showed a 38% reduction in the risk of breast cancer in women with the highest levels of the major melatonin, metabolite 6-sulfatoxymelatonin. In 2007, the International Agency for Research on Cancer (IARC) classified night-time shift work as probably carcinogenic to humans. It has been estimated that more than 4% of breast cancers in women in the UK, are linked to shift work.

Infections

It has been found that infectious substances are responsible for almost 22% of cancer deaths in the developing world and 6% in industrialised countries. Viral hepatitis B and C cause cancer of the liver; human papilloma virus infection causes cervical cancer; the bacterium Helicobacter pylori increases the risk of stomach cancer. In some countries, the parasitic infection schistosomiasis increases the risk of bladder cancer; and in other countries, the liver fluke increases the risk of cholangiocarcinoma of the bile ducts. Preventive measures include vaccination and prevention of infection and infestation.

Environmental pollution

In 2003, the international Agency for Research on Cancer (IARC) and the World Health Organisation (WHO) stated that air, water and soil with carcinogenic chemicals account for 1–4% of all cancers. Exposure to carcinogenic chemicals in the environment can arise via drinking water or pollution of indoor and ambient air. Exposure to carcinogens also occurs via the contamination of food by chemicals, such as aflatoxins or dioxins. Indoor air pollution from coal fires doubles the risk of lung cancer, particularly among non-smoking women (Smith, Mehta & Feuz, 2004). Worldwide, indoor air pollution from domestic coal fires is responsible for approximately 1.5% of all lung cancer deaths. Coal use in households is particularly widespread in Asia. There are numerous other chemicals which can increase the risk of a woman developing breast cancer.

Radiation

Ionising radiation is a significant breast cancer risk factor. Knowledge on the risk associated with radiation has been mainly acquired from epidemiological studies of the Japanese A-bomb survivors; as well as from studies of medical and occupational radiation exposure cohorts. Ionising radiation can induce leukaemia and a number of solid tumours, with higher risks for those at a young age during exposure. Residential exposure to radon gas from soil and building material is estimated to cause between 3% and 14% of all lung cancers; rendering it the second cause of lung cancer after tobacco smoke. 


Breast Cancer Prevention
Women who adopt proven and effective breast cancer preventive measures are less likely to be diagnosed with breast cancer. In contrast, women who fail to adopt breast cancer preventive measures are at a higher risk of being diagnosed with the disease. This book presents excellent breast cancer preventive measures, as approved by the most trusted breast cancer research institutions around the world. Considering the enormous complications associated with remedying breast cancer, all experts are unanimous on the truth that when it comes to breast cancer treatment, prevention is the best cure. 

 To view or download this book, click here.

 


No comments:

Post a Comment