What Causes Cancer
Cancer has now surpassed heart disease as the number one cause of death for Americans below 85.1 More than 10 million Americans have a history of invasive cancer. Two and one half million Americans will be diagnosed with cancer this year, (one million skin cancers). Cancer will claim over half a million victims this year.2 Why all this cancer? What causes cancer? Can it be avoided? What is the answer for cancer?
As a medical student, I was presented one day with a patient who had a lesion on his lower leg.
“Dr. Clark, examine Mr. Doe’s leg and tell the class your diagnosis.”
The leg was well developed and muscular with clean skin, except an ugly purple raised area.
“Does Mr. Doe have Kaposi’s sarcoma?” I queried, mostly guessing.
“Yes”, came the affirming reply, “And…” “Oh no,” I thought, “here comes another question.” “Why do you think Mr. Doe has Kaposi’s sarcoma?” To my limited knowledge Kaposi’s sarcoma occurred only in people with AIDS as a consequence of HIV infection, so I asked, “Is the patient HIV positive?”
“No”, came the reply, “but that is a good guess. Mr. Doe has had a kidney transplant and so is on drugs that suppress his immune system.”
This was my awakening to the fact that cancer often arises when the immune system is compromised or suppressed for any reason. It is true that Kaposi’s sarcoma is 1300x more likely to occur in AIDS patients, but lymphoma, (a cancer of the lymph glands throughout the whole body), is 135x more likely, and lung cancer about five times more likely to occur in HIV positive individuals. Just to give you a perspective, ALL cancers are more than twice as common in people whose immune system is disabled or compromised by HIV infection.
Some years ago a series of studies examined how sugar consumption weakens the immune system. Results showed that if a person ate no sugar for 12 hours, each white blood cell could destroy 14 dangerous bacteria. When 24 teaspoons of sugar were eaten (the amount in 2 cans of soda), the white blood cells were so compromised that they could only destroy one bacterium each.3
“But what does the immune system’s ability to eat bacteria have to do with cancer?” you may be asking. A diet high in refined carbohydrates such as sugar, starch, etc. suppresses the immune system, leaving the body unprotected from diseases like cancer. In fact studies show that a person on a high glycemic index diet (high in refined carbohydrates) has a significantly increased risk of acquiring breast,4 prostate,5 colorectal,6 endometrial,7 gastric,8 ovarian,9 or pancreatic1011 cancer. Malnutrition is another cause of a poor immune system. Malnutrition comes in two forms, severe caloric starvation and consumption of empty calories.12 Additionally as people get older their immune systems tend to age, losing the power to fight diseases like cancer.13
Cancer and Viruses
You may be wondering why cancer crops up in the absence of an active immune system. For this puzzle piece, let’s return for a minute to the AIDS/Kaposi’s association. Kaposi’s sarcoma is now known to be the result of a viral infection with either human herpes virus number 8 (HHV-8) or a virus known as Kaposi’s Sarcoma- associated Virus (KSV).14 More and more, infectious agents are being identified in relation to cancer.
So where do people get exposed to these infectious viruses? More and more, animal products such as beef, pork, chicken, turkey, milk and eggs are infected with cancer-causing viruses. Blood of workers in meatpacking plants show evidence of these viruses. These workers have an increased incidence of cancer, including cancers of the lung, mouth and throat, colon, bladder, and kidney.15 Poultry slaughterhouse workers have an increased incidence of throat cancer, liver cancer, lymphoma and leukemia.16
Animal products are known to increase the risk of cancer. The “Adventist Health Study” revealed that prostate cancer was 41% higher in meat eaters, colon cancer17 was 85% higher and ovarian cancer18 was 130% higher than in people who were vegetarians.
The Animal Connection
A study out of Harvard revealed that consumption of meat and dairy products doubles the risk of metastatic prostate cancer. Meat by itself increases metastatic prostate cancer by 66%. Processed meats such as bacon, beef, pork or lamb also increase the risk of metastatic prostate cancer.19
The increased risk of getting cancer from animals is not limited to the consumption of their bodies. In a 4 year case control study in Italy, the consumption of cheese was found to increase the risk of non-Hodgkin lymphoma by 66%.20
Compared to normal breasts, cancerous breasts have 3 times the incidence of infection with bovine leukemia virus, (a virus common in milk and meat).  There are other reasons for the meat/cancer association.
One of these is the way meat is prepared for marketing and the way it is cooked. Red meat is associated with increased formation of N- nitroso compounds. These compounds cause DNA damage which results in increased colorectal cancer.22 When people cook meat “well-done” at high temperatures, in an effort to kill all the trichina or “mad cow” disease, they produce mutagenic compounds called heterocyclic amines, which significantly increase the incidence of colorectal cancer.23
Animal foods prepared by frying, broiling or microwaving have been shown to increase the risk of cancer by the formation of toxins called heterocyclic amines.24
Protein, as much as we need it, is safe only in low quantities. Too much protein tends to suppress the immune system. Compared to a low protein diet (5%), a high protein diet (25%) like ours has been shown to both promote tumors and increase metastasis to the liver and lungs.25
Let’s take a minute to look a little closer at dairy products. To begin with, it will help you to know that one of the important parts of your immune system is a white cell called the “natural killer cell”. Milk is immunosuppressive—the more you drink, the worse your natural killer cells will function. What’s more, tripling your milk protein intake triples your cancer risk.26 One of the reasons for this is that cows are fed high protein diets and given growth hormones.27 Cows today produce more milk than they did 100 years ago. Three servings of milk per day significantly increase insulin like growth factor in humans.28 Insulin-like growth factor elevation is linked to cancer of the prostate,29 breast,3031 and lung.32
Hormones and Cancer
At this point it would be well to understand the role of hormones in breast cancer initiation and progression. Anything that increases or prolongs a woman’s exposure to estrogen increases her risk of breast cancer. Estradiol, one of the estrogens, is a potent cell growth stimulator, which is why it also can promote cancer. Thus there is a greater incidence of cancer associated with: early onset of menarche, late menopause, (because the woman is exposed to more years of elevated hormones), hormone replacement therapy, postmenopausal obesity, (because fat cells can produce estrogen) and history of an abortion (because after the loss of the fetus the woman is exposed to the estrogens that were meant to support the pregnancy).33
One often unrecognized source of large doses of growth hormones comes from the use of animal foods. Estradiol is used as a growth promoter in farm animals. Estradiol can actually induce tumors in rats, mice, and hamsters. When levels become artificially elevated in humans there is a corresponding increase in breast and uterine cancer.34 Postmenopausal women with estradiol levels > 9 units (in their entire blood volume) had a 7-fold higher rate of breast cancer than that of women with undetectable levels.35 If a level of nine or greater is bad, you may ask, what would be a source of estradiol that might send my hormones that high? I was interested to find that one American beefsteak had 20 units, one liter of milk 18 units, 2 eggs 13 units, 50 gm of butter 4 units, and 100 gm of cheese 3units!36
Another food that will drive up your hormones is fat. Studies show that high dietary fat intake is associated with elevated serum estrogens and androgens.37 In 1975 Carroll and Khor produced charts showing increased rates of breast, colon, and prostate cancer with increased calorie, fat, and protein intake, country by country. There was a linear relationship between a country’s per capita fat intake and the death rate from cancer.38 Some fats are more dangerous than others. High saturated fat intake triples the risk of dying from prostate cancer.39 Another dangerous fat is the chemically produced fat known as trans-fat. Trans-fat intake has been shown to increases breast,40 prostate,41 and colon cancer.42
My first clinical experience was in gynecology/obstetrics. Besides delivering babies and attending surgeries, much of my time was spent in clinic. Within a few days it became very apparent that from the day a girl came in complaining of discomfort with the onset of menses to the time that a middle aged women came in to tell of her discomfort with hot flashes, we had women on pharmacological doses of hormones.
“And what are the consequences?” you may ask.
In a study of 37,000 women, oral contraceptives significantly increased breast cancer risk.4344 Perimenopausal hormone-replacement therapy with estrogen alone increases the risk of endometrial cancer by 45%.45 And when estrogen is combined with progesterone, breast cancer increases.46 Some replacement hormones are from “natural” sources such as pregnant horse urine. But many are simply chemicals from the laboratory.
Vitamin D and Sunshine
Vitamin D has received a lot of attention recently as an immune stimulator and an anti-cancer agent. Its primary source is ultra-violet light striking the skin.
“But”, you may say, “sun causes skin cancer.” Here is where the discriminating mind will discern the real cause of skin cancer. In a study of precancerous skin lesions, it was found that people on a high fat diet developed three times the number of lesions compared to those on a low fat diet. Thus, in order to get your anti-cancer vitamin D from the sun, you need also to limit the fat in your diet.47
We have been talking about the fat that you eat, but now we need to make mention of the fat that you wear. Fat cells are actually involved in estrogen production. Excess estrogen production in obese women gives them a greater risk of dying with breast cancer.48 Obesity is also a risk factor for pancreatic cancer49, not to mention diabetes and arthritis. Don’t underestimate the contribution of overeating of any kind to the development of cancer.50 When you consume extra food, it tends not only to make you grow, but to make cancer grow also.51
Obesity is usually linked with elevated triglycerides and cholesterol. Elevated cholesterol and triglycerides are associated with significant increases in breast cancer. On the other hand, high levels of HDL, the good cholesterol, significantly decrease breast cancer risk.52
This brings us to out next topic—chemicals in our environment. Chemicals can act like hormones, increasing the risk of cancer.53 Insecticides such as DDT and DDD have hormonal activity54 suppressing the immune system,5556 and increasing the risk of cancer.57 Chemicals tend to accumulate in our environment. Plants can take on small portions of these chemicals. Small creatures eat the plants and then are eaten by larger ones. As you go up the food chain a process called biomagnification occurs. For example sea otters tested for PCBs and DDT showed up to 240x greater levels than that found in their prey.58 The closer to the beginning of the food chain (eat from the garden) the safer your food.
The body is constantly surveying its DNA for damage and making repairs. When DNA damage accumulates, cancer can result. It has been found that lung cancer patients have suppressed DNA repair.59 One commonly encountered substance, which prevents repair of damaged DNA, is caffeine.60 Consequently, two or more cups of coffee per day more than double the risk of ovarian cancer.61 What’s more, when caffeine is combined with a high fat diet, it significantly increases breast cancer risk.62
In this age of scientific discovery, the lung cancer/tobacco connection need hardly be mentioned. But few realize the extent to which other cancers are affected by this poison. Tobacco’s influence can be seen in many malignancies, including cancers of the lip, mouth, throat, voice box, trachea, esophagus, stomach, liver, pancreas, bladder, kidney, cervix, leukemia, colon, skin, and penis.63
Alcohol, a poison to the cells, is involved in 75% of esophageal cancers, 50% of mouth and larynx cancers, 30% of liver cancers, as well as colon, rectal and breast cancer. All totaled, 60,000 deaths per year are related to, not traffic accidents, domestic violence or homicides, but alcohol related cancer.64
New building materials are a common source environmental toxins.
Workers in a newly remodeled office were found to have increased chemicals in their blood stream and significant decline in their immune function.65 Cancer causing chemicals found indoors include: chloroform, acetaldehyde, formaldehyde, dichlorobenzene, styrene, methylene chloride.66
Another source of environmental toxins is the chemicals added to food as preservatives or flavor enhancers.67 There are many additives to food for which side effects are unknown. Others are questionable or have produced cancer in animals such as BHA,6869 BHT,707172 and potassium bromate,73747576 etc.
In our modern age of plastics more and more of our food is being presented to us in poly containers. Today we get products such as milk, peanut butter, bottled water, apple sauce, and some jams, just to name a few, in plastic containers. It might cause concern to realize that the people making these containers—workers at plastic factories, have 5x the risk of pancreatic and liver cancer.77
A lot of the toxic chemicals in our environment that have carcinogenic potential are halogenated polycarbons. The most common halogens in these substances are fluoride,7879 bromide, or chloride. In these compounds, a halogen such as chloride is attached to a carbon structure, like gasoline, which makes the carbon structure more toxic and poisonous. Should it be any surprise to discover that these halogens are not much better for us if put in our water? A study in Canada revealed that consumption of chlorinated water increases the risk of cancer of the esophagus and stomach and leukemia.8081
When I was a medical student I did research with the General Surgery Department. I was looking at the previous five years of pancreatic cancer patients. To my surprise, none of them was still alive. All had died, and this usually after several surgeries and much pain. The risk of pancreatic cancer is significantly increased by obesity82 and high consumption of: salt, smoked meat, fried food, refined sugar, food with preservatives or additives,83 and coffee.848586 Salt also increases the risk of brain cancer.87 Knowing the risk factors helps us understand what lifestyle changes we can make to improve our chances of avoiding this killer disease.
We all have seen a diesel truck grinding its way up a hill belching black smoke from its exhaust pipe. Products of combustion surround us even in our everyday life (exhaust from cars, gas stoves, etc.) all of which have carcinogenic potential.88 Railroad workers exposed to diesel fumes have a 40% increase in mortality from lung cancer.89
In recent years the phrase “oxidative stress” has become popular. Oxidative stress is merely a measure of the inflammation in the body. Measuring the number of free radicals in the blood often assesses this. Oxidative stress damages DNA that leads to the development of cancer. Chronic inflammation increases the risk of cancer in the gastrointestinal tract.90 For example gastro-esophageal reflux can cause esophagitis, known as Barrett’s Esophagus. In Barrett’s Esophagus, cancer develops because the esophagus is constantly healing itself and just can’t stop healing.91 Cancer is basically cells that are growing or healing out of control.
Melatonin is a protective, anti-cancer hormone and strong antioxidant.92 Light at night suppresses melatonin and increases cancer cell growth rates. Evidence now links exposures to light at night to elevated breast93 and colorectal cancers in night workers.94
Stress and depression increase cancer because they decrease the immune system’s ability to find and destroy cancer cells.9596 In a ten year follow up study, in which social coping skills, along with the traditional risk factors; smoking, drinking and medical diseases were considered, people with greater stress from poor interpersonal skills had a 40% higher death rate from cancer.97 In another study, divorced or separated women had a 126% higher risk of getting breast cancer, and widowed 100% higher.98 Cancer develops more commonly and grows faster in people with suppressed anger.99 These mental / emotional causes of cancer are some of the most powerful risk factors known to man.
One threat to DNA integrity is all the modern sources of radiation. Sources of radiation include radioactive elements, X-rays, gamma rays, microwaves, radio transmitters, electromagnetic fields, ultraviolet light, solar radiation, and nuclear radiation. For example children living within 2 km of an AM radio station have more than double the chances of getting leukemia as those 20 km or more away.100
Another modern source of radiation is the cell phone. Cell phones significantly increase astrocytomas (brain cancer) in the temporal area of the brain (right where you hold your cell phone). There is also an increase in acoustic neurinomas (ear cancer).101
Electric blankets can also be a significant source of radiation. Breast cancer risk associated with electric blanket use increases with the number of years of use, the number of seasons of use, and the length of time of use each night.102 It has been suggested that if you want your bed warmed, turn on the electric blanket or heating pad until the desired temperature is reached, then unplug it before getting into bed.
The relation between breast cancer and electromagnetic field exposure has been the object of much study. For women telephone installers, repairers, and line workers, the risk of breast cancer goes up 117%; for system analysts and programmers 65%; for telegraph and radio operators 40%; and for telephone operators 27%.103
Children are affected by radiation as well. For example the risk of leukemia is elevated in: children whose mothers used an electric blanket or an electric mattress pad during pregnancy; children who themselves use electric blankets or electric mattress pads, hair dryers, video machines in arcades, or video games connected to a television.104
Elevated levels of heavy metals including: iron, nickel, chromium, zinc, cadmium, mercury, and lead have been found in tumorous tissues of cancer patients.105 These heavy metals increase oxidative stress and DNA damage, which result in cancer. Mercury, when combined with chloride, produces cancer by acting as a hormone, binding to and activating estrogen receptors.106
Continued in Cancer: What’s Eating You? – Part 2
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