Do Estrogens In Soy Increase Prostate Cancer Risk?
At present, confusion and controversy surround the inclusion of soy in the diet of those men at risk for developing prostate cancer.
Research on soy and prostate cancer presents a conflicting picture.
A Japanese study published in Cancer Epidemiology Biomarkers & Prevention found a correlation between increased intake of soy isoflavones and decreased risk of localized prostate cancer.
The 20 year study of 8000 Japanese men in Hawaii found a direct correlation between tofu consumption and lower rates of prostate cancer. Those who consumed tofu once a week or less were three times as likely to get prostate cancer as those who ate it daily.
The same study found, however, that a high intake of these compounds correlated with more severe cases of advanced prostate cancer.
The benefits of soy
Countries that have a high intake of soy in their diet tend to have much lower rates of prostate cancer compared to countries where soy intake is fairly low.
Plant chemicals known as isoflavones are thought to play a key role in soy’s amazing cancer-protecting qualities. One isoflavone in particular, genistein, has been found to be effective in slowing the progression of prostate cancer.
In a study conducted at the University of California in the US, scientists added genistein to a culture of human prostate cancer cells. It was found to spur the production of a gene called p21, which inhibits the manufacture of a protein that cancer cells need to grow, so causing the cancer cells to die off. Animal studies have confirmed that genistein can reduce the size of prostate cancer tumors.
How can soy benefit prostate cancer?
The protection against cancer may come from phyto-oestrogens in soy. Phyto-oestrogens are chemicals found in plant foods (phyto means ‘plant’). They are similar to the female sex hormone oestrogen. There are different types of phyto-oestrogens. Some are found in soya bean products. Others are found in the fiber of whole grains, fruit, vegetables and flax seed. Milk may also contain phyto-oestrogens, but this depends on what the cows have been eating.
The isoflavones in soy keep cells from going rowdy,” says researcher Nagi B. Kumar, PhD, RD, of the Moffitt Cancer Center in Tampa, who headed that study in Prostate. “Most cells function, mature, and eventually die off. But some cells are mutated, and they proliferate in a way that’s pointless, progressive, and wild. That’s what causes cancer, and soy seems to help stop this.”
Daidzein, another soybean estrogen generously supplied by these soy foods, is now under intense study for its potential cancer-fighting and bone-building qualities. It, like genistein, is turned by intestinal bacteria into a substance that competes with human estrogen. Although other foods contain phytosterols, no other commonly consumed foods contain these two powerful phytoestrogens. And it has been proven in human studies that isoflavones in the diet are absorbed into the bloodstream– one study in which volunteers ate 40 grams of textured soy protein daily for just five days, the isoflavone levels in their urine (which indicates their presence in the bloodstream) increased as much as thousand-fold in comparison to levels taken before the study.
On the other hand…..
Soy apparently has many beneficial constituents along with harmful ones.
Dietary genistein and highly processed soy agents have been found to stimulate growth in the MCF-7 prostate cancer cells, and to promote prostate cancer in ovaraectomised athymic mice models.
Non-fermented soy contains allergens, several toxins, and (particularly if uncooked, unfermented, & unsprouted) powerful protease inhibitors, which inhibit the critical anti-cancer action of proteolytic enzymes, particularly trypsin.
Far from being the perfect food, modern soy products contain anti-nutrients and toxins and they interfere with the absorption of vitamins and minerals.”
Unfermented soy contains high levels of a number of compounds that can: block the absorption of calcium, magnesium, iron and zinc; stunt growth; and alter hormone levels, disrupting menstruation, lowering testosterone, increasing the risk of breast cancer, and causing thyroid and prostate complications!. Unfermented soy includes things like soy milk, soy burgers and soy hot dogs,
Soybeans ontains large quantities of natural toxins or “anti-nutrients”. First among them are potent enzyme inhibitors that block the action of trypsin and other enzymes needed for protein digestion.
These inhibitors are large, tightly folded proteins that are not completely deactivated during ordinary cooking. They can produce serious gastric distress, reduced protein digestion and chronic deficiencies in amino acid uptake. In test animals, diets high in trypsin inhibitors cause enlargement and pathological conditions of the pancreas, including cancer.14
Practical common-sense conclusions:
Avoid Unfermented soy products -Only eat fermented soy products
In order to derive some benefit from soy, consume only fermented soy products – such as organic miso (mugi barley and genmai miso are the best), organic tempeh, soy sauce or tamari and natto.
Fermented soy products have the highest levels of cancer-fighting nutrients. Fermented soy products are known to contain high concentrations of the isoflavone, genistein, and other compounds that exhibit anticancer activity in preclinical models. This is because the phytic acid, which is inherent in soy beans, has been neutralized in the process of fermentation. In addition, consuming fermented soy is very beneficial in recolonizing the friendly bacteria in the large intestine, which neutralizes the ‘unfriendly’ bacteria and allows for greater general assimilation of foods and nutrients.
Fermentation is the only way to rid soy of its undesirable constituents and “kill” the anti-nutrients it contains.
One problem, until the development of the fermentation process, was that the beneficial soy isoflavones are only present in fairly small amounts in unfermented soya products. For example, a recent Japanese study has found that the level of genistein in fermented soy products is far higher than in unfermented soy beans, soy milk or tofu.
Fermentation also doesn’t involve the multiple chemical processes required in the production of tofu and other processed soy products.
A highly recommended fermented soy beverage product is Haelan 951 – A Revolutionary New Type Of Soy Drink That Could Offer Vital Protection Against prostate Cancer.
A number of fermented soy extracts are sold as nutritional supplements. Perhaps the most popular of these in the cancer world is Haelan 951. According to the manufacturer, “Haelan’s (patented) fermentation process hydrolyzes many of the soy bean proteins into amino acids and compounds that are rich in nitrogen and fermentation metabolites of the naturally occurring isoflavones such as genistein, protease inhibitors, saponins, phytosterols, and inositol hexaphosphate (IP-6) compounds in soy beans.” It is described as “an excellent source of pre-digested soy proteins”. It is a thick, beige, bitter-tasting liquid.
Haelan 951 may prove effective against recurrent cases of prostate cancer
US cancer specialists at the Prostate Cancer Research and Education Foundation in California carried out a small trial in 1998 with 12 patients who all had a history of recurrent prostate cancer and rising levels of prostate specific antigen (PSA) – an indicator of the severity of the disease. All of the patients were given a fermented soy drink, in this case Haelan 851 (an earlier version of Haelan 951). The researchers found that half of the patients in the study responded to the treatment with a drop in their PSA levels.
Individual case studies also support the effectiveness of Haelan 951. One 58 year-old man was first diagnosed with a prostate tumor following a biopsy three years ago. His doctor recommended either surgery to remove his prostate gland, or radiotherapy. The patient refused both options and instead started taking Haelan 951, two weeks after receiving the diagnosis. His PSA levels have remained stable for three years and, at his last check-up, his prostate gland appeared perfectly normal on rectal examination and ultrasound scan.
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The Benefits of Fermented Soy Products for Breast Cancer
Refined Carbohydrates and Breast Cancer Risk
