THE MEDICAL BENEFITS OF SOY:
"this is a long page, well worth the reading"
The Role of Soy in Preventing and Treating Chronic
Disease was the title of an international symposium held in September 1996. Papers presented at this
conference showed that soy can: 1) Prevent cancer at multiple sites 2) Replace estrogen in some
menopausal women 3) Prevent gallstones 4) Protect kidney function 5) Stimulate bone formation 6)
Lower cholesterol levels 7) Inhibit LDL cholesterol oxidation 8) Prevent atherosclerosis 9) Inhibit
proliferation of cancer cells Soy and Cancer Prevention
When Japanese women move to the U.S., their risk of breast cancer increases dramatically. It was
previously thought that the high-fat Western diet caused this increased risk of breast cancer, but new
studies fail to show a significant link between dietary fat and breast cancer risk. This has led to the
suggestion that the increase in breast cancer incidence may be a soy deficiency.
In the Journal of Cellular Biochemistry (Suppl. 22 1995), an article was published entitled,
"Rationale for the use of genistein-containing soy matrices in chemoprevention trials for breast and
The article stated that Oriental populations who have low rates of breast/prostate cancer consume
20-80 mg a day of genistein, almost entirely derived from soy, whereas in the United States, the
dietary intake of genistein is only 1-3 mg a day.
Breast and prostate cancers are running at epidemic levels in the United States. Every year, more
Americans are being diagnosed with these cancers.
Genistein and other soy components provide specific anti-cancer protection that is not obtained
through antioxidant supplements.
Soy may prevent and treat some cancer in the following ways:
1) Pesticide residue binds to estrogen-testosterone cell receptor sites in the breast and prostate, thus
causing abnormal cell proliferation that can lead to cancer. Soy has been shown to block the
estrogen-testosterone cell mutating actions of pesticides, herbicides, fungicides, and other pollutants.
2) Tyrosine kinase is an enzyme that is required for most tumor cell proliferation. Soy has been
shown to safely inhibit tyrosine kinase activity, thus slowing down cancer cell growth.
3) Tumors grow new blood vessels to support the rapidly growing number of cancer cells. Soy has
been shown to have an angiogenesis inhibiting effect that prevents new blood vessel growth into
4) The hormones estrogen and testosterone promote cell growth Throughout the body. These
hormones may also cause breast/prostate cancer. Soy modulates the effects of estrogen and
testosterone in a favorable way, thus reducing their risk of inducing cancer.
5) Cancer cells have very effective protein synthesis mechanisms that enable them to divide
indefinately. Soy inhibits cancer cell protein synthesis, but does not affect normal cell protein
6) Cancer cells fail to properly differentiate into normal cells, thus continuing to divide and
enventually overwhelm healthly cells. Soy has been shown to induce cancer cells to differentiate into
Soy's multiple anti-cancer mechanisms are causing scientists throughout the world to study the use of
soy in prevention and treatment of cancer. Published papers show the potential of soy extracts to be
effective in treating cancers of the colon, liver, lung, breast, prostate and some forms of leukemia.
We can now show that not only do people who consume large amounts of soy in their diets have a
lower than average risk of cancer, but that those with specific types of cancer can now look to
isoflavone-rich supplements as a way to help fight the disease
A research team headed by Dr. C.H. Adlercreutz of Helsinki University Central Hospital in Finland
published a report in the Journal of Nutrition (15, 3 Suppl, 757S-770S, 1995) in which they found
"Because many Western diseases are hormone dependent cancers, we have postulated that the
Western diet, compared with a vegetarian or semi-vegetarian diet, may alter hormone production,
metabolism or action at the cellular level. Recently, our interest has been focused on the
cancer-protective role of the lignans and isoflavonoids [found in high concentrations in soy].
"The plant lignan and isoflavonoid glycosides are converted by intestinal bacteria to hormone-like
compounds with weak estrogenic and antioxidative activity; they have now been shown to influence
not only sex hormone metabolism and biological activity, but also intracellular enzymes, protein
synthesis, growth factor action, malignant cell proliferation, differentiation and angiogenesis, making
them strong candidates for a role as natural cancer protective compounds. "Epidemiological
investigations support this hypothesis, because the highest levels of these compounds are found in
countries or regions with low cancer incidence. This report is a review of results that suggest that the
diphenolic isoflavonoids and lignans are natural cancer-protective compounds." Genistein And
The increasing numbers of men being diagnosed with prostate cancer (1995 estimates are 240,000
men in the U.S. alone) has brought this disease to the center of media attention. With the new
developments in soy products, we havetaken new interest in a 1994 study by Drs. H.R. Nalk and
K.J. Pienta of the Wayne State University School of Medicine in Detroit, who conducted much of
the research on Modified Citrus Pectin, which has been shown to protect against the metastasis of
Here is a quote from their paper, which investigated the antitumor effects of genistein on hormone
refractory prostate cancer (Anticancer Research, Nov-Dec, 1994, 14(6B), 2617-9:
"In vitro genistein appears to be cytotoxic to both the rat prostate cancer cell line MAT-LyLu and
the human prostate adenocarcinoma cell line, PC-3. In vivo, however, genistein failed to significantly
inhibit the growth of subcutaneously implanted MAT-LyLu cells."
Another publication by Dr. G. Peterson of the University of Alabama at Birmingham showed that
genistein inhibited the growth of human prostate cancer cells:
"The effect of the isoflavones, genistein, daidzein, and biochanin A on the growth of the LNCaP and
DU-145 human prostate cancer cell lines has been examined. Genistein (inhibited) both serum and
EGF- stimulated growth of LNCaP and DU-145 cells (IC50 values from 8.0 to 27 micrograms/ml
for serum and 4.3 to 15 micrograms/ml for EGF)." Both reports suggest that, while the effectiveness
of isoflavones for prostate cancer has not been proven conclusively, Life Extensionists would
nevertheless be wise to consider it as an integral part of their cancer treatment protocol and cancer
Genistein And Breast Cancer
Scientific evidence points to man-made chemicals as a cause of cancer. Only recently have
researchers discovered that many of the most popular insecticides, fungicides, manufacturing
chemicals, and other chlorine-based substances actually mimic estrogen, the female hormone. These
substances are called "hormone modulating pollutants." They are fat soluble substances that actually
accumulate in the body over time, and are being recognized as a contributing factor in the
development of hormone-related cancers. Women with breast cancer have high levels of
estrogen-altering pesticide residue in their breast fat cells compared to women who do not have
breast cancer. Both prostate cancer and breast cancer are believed to be hormonally related.
The latest research in phytochemicals shows that the soybean plant contains "friendly estrogens,"
forms of the hormone which have been shown to prevent or treat hormonally related cancers. One
important study from Italy by Dr. M.C.Pagliacci published in the European Journal Of Cancer (Eur J
Cancer, 1994, 30A(11):1575-92) analyzed the effects of genistein on the number of cells and the
cell cycle progression of human breast cancer cells.
Here is a quote from the original research paper on the growth inhibitory effects of genistein on
MCF-7 human breast cancer cells:
"Genistein, a natural isoflavonoid phytoestrogen, inhibits the tyrosine kinase activity of growth factor
receptors and oncogene products, as well as the in vitro growth of some tumor cell lines. The low
incidence of breast cancer in countries with a flavonoid-rich soy-based diet and the protection
afforded by soy-derived products against experimental mammary tumors in rats suggests that
genistein and other isoflavonoid compounds may exert anti-tumor activity." We analyzed the effects
of genistein on cell number and cell cycle progression in human breast cancer cells (MCF-y) in vitro.
Genistein produced a significant dose-dependent inhibition of MCF-7 cell growth. The growth
inhibitory activity of genistein in MCF-7 cells results from the sum of cytostatic and apoptotic effects.
"In conclusion, the dietary phytoestrogen genistein inhibits in vitro growth of MCF-7 human breast
cancer cells through blocks in the 'critical checkpoints' of cell cycle control and induction of
Other Isoflavones Show Strong Anticancer Potential
. An important study by Dr. Xu at Iowa State University provides evidence for the health benefits of
daidzein, which he showed to be more bioavailable than genistein in adult women (J. Nutrition, June
1994, 124(6), 825-32). The Foundation's new soy extract is the first product on the market that
contains a significant amount of daidzien.
Using Soy Extract In Place Of Premarin
There may be enough natural phytoestrogens in soy for some women to derive safe estrogen
replacement therapy. As has been previously reported, FDA-approved estrogen drugs like Premarin
have been shown to statistically increase the risk of breast, ovarian and uterine cancers, whereas soy
consumption has shown an anti- cancer effect.
Estrogen is an anti-aging hormone that provides many beneficial effects throughout the body. The
one significant drawback to estrogen replacement therapy is the increased risk of certain cancers.
Natural phytoestrogens have been proposed as methods of replacing estrogen without using potent
Each woman taking Premarin and other estrogen drugs will have to ascertain if consumming large
amounts of soy can effectively substitute for estrogen drugs. Blood tests that show a complete
hormone profile can help ascertain this.