Estrogens
Human Estrogen is an important cause of breast cancer. 16-a hydroxyestrone a metabolite of
estrogen - activates estrogen receptors that may trigger breast cancer by strongly increasing the
interaction between estrogen receptors and growth-promoting genes, enhancing breast-cell
proliferation and perhaps damaging DNA.
A variety of factors impact the levels of "bad" estrogen metabolites. Reducing fat in the diet
below 20% of calories lowers estrogen levels, which in turn reduces 16-a hydroxyestrone.
Phytoestrogens found in foods such as Soy, Apples, Rhubarb, Carrots, Pomegranate seeds,
Dates, Onions, Radishes, Cucumbers, Peas, Cabbage, Legumes & Hops yield 2-hydroxyestrone
which blocks 16-a hydroxyestrone. Asian females who have a reduced incidence of breast cancer
have higher levels of 2-hydroxyestrone and lower levels of 16-a hydroxyestrone than non-Asian
women and they eat more soy products and green vegetables. A case control study in
European women similarly demonstrates the protective effects of dietary phytoestrogens.
Cruicferous Vegetables (Broccoli, Brussels Sprouts, Cabbage, Cauliflower) have
isothiocyanates such as indole-3-carbinol that also increase the 2:16-a- hydroxyestrone ratio, and
therefore has anti-carcinogenic potential. Young broccoli sprouts contain 30 to 50
4
times the amount of isothiocyanates found in mature broccoli heads. To cut the risk of cancer in
half, experts suggest consuming 2 pounds of broccoli and similar cruciferous vegetables a week.
However, with the potency of broccoli sprouts, the individual would need to consume only 1
ounce of sprouts to get the same benefit. Fruit and vegetable fiber also possesses a strong
significant inverse association with breast cancer risk. The rationale for the benefit
of dietary fiber in breast cancer risk reduction includes:
1. A high fiber diet reduces circulating estrogens by reducing enterohepatic recirculation of
estrogen.
2. Many plants and vegetables contain isoflavones and lignans which are capable of being
converted into weak estrogens in the bowel that may compete with estrogen binding sites.
3. A high fiber diet is generally not associated with obesity.
4. A high fiber diet usually has a lower content of fat and a higher content of antioxidant
vitamins, which may protect against breast cancer.
5. Diets rich in fiber and complex carbohydrates can improve insulin sensitivity with
associated reduction in circulating estrogen levels.
Xenoestrogens - "Endocrine Disruptors"
DDT, polychlorinated biphenyls and other chlorinated organic are xenobiotics that alter the
body's own production and metabolism of estrogen. The list of ubiquitous xenoestrogens
includes insecticides such as DDT and methoxychlor, synthetic estrogens, aromatic
hydrocarbons and breakdown components of plastics and a common weed killer Atrazine.
Potentially harmful xenoestrogens also include gasoline, car emissions, synthetic estrogens and
antidepressive drugs.
Medical Estrogens
Estrogen Replacement Therapy (ERT) for menopausal women increases risk for women aged 60
to 64 Oral contraceptives slightly increase the risk of having breast cancer
diagnosed.The data shows that the relationship between oral contraceptives and breast
cancer in younger women appears to have a biological basis rather than an artifact or result of
bias [xxxi] There is a new class of medical estrogens called selective estrogen receptor
modulators (SERM) that act like phytoestrogens and may reduce breast cancer by up to 50%,
but, unlike soy products and other vegetable phytoestogens, SERMs may induce cancer of the
ovary. Raloxifene (Evista) is the first drug in this class to reach the market.
Dietary Fat & Eicosanoids
Data regarding the relationship to fat in the diet to breast cancer has been inconsistent. Studies have suggested high intakes of dietary fat result in higher levels of
estrogens. It is also possible that industrial chemicals (antibiotics, hormones or pesticides)
contaminating meat are the culprits. It also appears that some types of
fat particularly fish oil and olive oil are protective against breast cancer, while animal
fats and polyunsaturated vegetable oils promote breast cancer. Again, Omega-3 fatty acids mainly fish oil - suppress breast cancer.There is an inverse relationship between the
incidence of breast cancer and the level of fish consumption, which suggests a role for omega-3
fatty acids in the prevention of breast cancer. 5
Fats produce chemicals called Eicosanoids in the body. Some Eicosanoids promote breast
cancer, while others prevent it. This is why some fats, like red meat fats (so called saturated fats),
promote breast cancer, while Omega-3 fats protect. Interestingly, Aspirin and other antiinflammatory drugs influence the metabolism of fats into Eicosanoids and can prevent breast
cancer. In evaluating 511 breast cancer patients compared to 1,534 control subjects, women
using nonsteroidal anti-inflammatory medications at least 3 times a week for more than 1 year
had an odds ratio of .66 (that is a 34% reduction). There were similar odds ratios for the use of
ibuprofen and aspirin. Aspirin also reduces the risk of heart attack, and some kinds of
stroke through the same chemistry; however, it increases the risk of bleeding.
Insulin & Syndrome-X
Americans are becoming progressively obese because of diet and and sedentary lifestyle. This is
a risk factor for a wide variety of diseases including breast cancer. Increased body mass
results in increased insulin levels. This is called syndrome-x. Insulin appears to trigger breast
cancer. The fattest third have a 1.9-fold higher risk of dying from breast cancer than the thinnest
third. The epidemic of obesity is a complex social phenomenon, related to sedentary
lifestyle, decreased fiber consumption, decreased fruit and vegetable consumption and increased
junk food consumption. Breast cancer risk is just the tip of the iceberg!
Antioxidants
Because human being breathe oxygen, using it to "burn" fuel for energy, we are vulnerable to
oxidative damage from the sparks (free radicals), that are an inevitable consequence of this
chemistry. Free radicals are a major cause of aging, and through damaging DNA are major
causes of breast cancer.
Life on earth depends on antioxidants, which "scavenge" free radicals and dispose of them
safely. Our bodies have several built in anti-oxidant systems, which require nutritional factors to
function properly. Some of these factors are vitamins, some are minerals, and some are other
chemicals found chiefly in fruits and vegetables. There have been important observations
regarding the protective effects against breast cancer for Carotenoids (from carrots and other
vegetables), Retinol (Vitamin A) and Vitamin E. Vitamin C intake has a strong
significant inverse association with breast cancer risk. Selenium in the range of 1.00-1.21
umol/L showed a significant preventive effect.[lv]
While taking vitamins may confer some protection from breast cancer, it should be emphasized
that a wide variety of plant-based foods may be more important. Green Tea- current studies
show an inverse association between green tea consumption and the number of axillary lymph
node mets, as well as decreased recurrence of stage I and II breast cancer. Limonene (from
lime and other citrus fruits) in a rat model - caused complete regression of both mammary
cancers. Flavonoids are polyphenolic antioxidants that occur naturally in fruits, vegetables
and in beverages such as tea and wine. Many of them are scavengers of free radicals,
antioxidants, chelating agents, and modifiers of enzymatic and other biological functions.Silymarin, a flavonoid antioxidant, has anticarcinogenic effects in human breast cancer 6 Carotenoids (beta-cryptoxanthin, lycopene, and lutein/zeaxanthin) may protect against breast
cancer.
Other Micronutrients
Vitamin D - An ecological study showed a strong inverse correlation between breast cancer
mortality in the United States and ultraviolet sunlight, suggesting low vitamin D levels may play
a part in breast cancer. Garlic has considerable evidence supporting its anticancer effect. The
chemo preventive potential of garlic in inhibiting tumor genesis lies in the presence of
organosulfur compounds such as diallylsulfide, diallydisulfide and diallylpolysulfides,
thiosulfinates, sulfoxides, S-allylcysteine. Alcohol consumption is clearly associated with breast cancer, while Folate (a B vitamin) reduces
this risk. The Nurses' Health Study of 88,000 women for 16 years, revealed 3,483 incident cases
of invasive breast cancer. There was a direct association with breast cancer and the number of
drinks consumed. One drink per night (such as wine) increased risk by 50%, two drinks doubled
risk, however, folate consumption (such as in multi-vitamins and leafy green vegetables)
mitigated this risk as well as the risk of colon cancer and and coronary heart disease. Lactation
As mentioned previously, the longer a woman breast feeds, the lower her risk of breast
cancer.
Tobacco
The odds ratio of breast cancer for ever active smokers compared to women who were
unexposed to either passive or active smoke was 2.2 for an average lifetime consumption of 1 to
9 cigarettes per day, 2.7 for 10 to 19 cigarettes per day and 4.6 for 20 or more cigarettes per day.
The odds ratio was 3.2 among passive smokers who were exposed for an equivalent of 2 hours
per day for 25 years. Active and passive exposure to tobacco smoke may increase the risk to
breast cancer.
Stress
In evaluating 119 consecutive women between 27 years of age who were referred for biopsy of
suspicious lesions, 41 were diagnosed as having malignant disease. After adjusting for variables,
severe life events increased the risk to breast cancer with an odds ratio of 11.6. There appears
to be an etiologic association between life stress and breast cancer. Moreover, support
groups are more beneficial to breast cancer patients than chemotherapy.There may be
some specific psychodynamic issues related to breast cancer.
More information here :
Specific Breast Cancer Promoters & Prevention Strategies
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