The Good And Bad About Soy ”second part”
The following shows the soy protein content of some common unfermented soy products. Are you eating multiple servings of these everyday?
Unfermented Soy Foods_____Serving Size_____Protein (grams)
Soy protein isolate____________1 oz_____________25
Soy nuts, roasted_____________1/2 cup___________22
Soy burger__________________1 patty___________14
Tofu, firm___________________4 oz_____________14
Edamame, boiled_____________1/2 cup__________12
Soy milk____________________8 oz______________8
Soy nut butter________________2 Tbsp.___________8
Soy cheese__________________1 oz______________6
Soy yogurt__________________4 oz______________4
Furthermore, unfermented soy is a hidden component of the American diet. Research estimates that soy is present in 70% of all supermarket products and widely used in fast food chains.
Soy is used to bulk up and bind many processed foods so that food firms can put a higher protein value on them.
The husk of the soybean is used for fiber in breads, cereals, and snacks.
The big one is soybean oil which is the most consumed vegetable oil in the world. It is used in frying oils, salad dressings, and many processed foods.
Last but not least, 70% of the soybeans grown in the U.S. are used for animal feed, with poultry being the highest livestock sector consuming soybeans, followed by hogs, dairy, beef, and aquaculture. These soy-fed animals are then eaten by us.
Soy is largely genetically modified. 94% of the soy planted in the U.S. is “Roundup Ready”, which means it is genetically bioengineered to survive heavy application of Monsanto’s toxic Roundup herbicide. In March 2019, a San Francisco federal jury unanimously agreed that Roundup caused a man’s non-Hodgkins lymphoma. The verdict is the second in the U.S. to find a connection between the herbicide’s key ingredient glyphosate and cancer. Therefore, even if you are eating fermented soy, make sure it is organically grown.
Soy is one of the top eight allergens. They are cow’s milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, and soybean. These foods account for about 90% of all food allergies. If you have a soy allergy or sensitivity, watch out for “hidden” soy as it is often used in many processed food products.
Research On Soy And Disease
Soy is unique in that it contains a high concentration of isoflavones or plant estrogens (called genistein and daidzein) that are structurally similar to human estrogen but with weaker effects. They can bind to estrogen receptors in numerous tissues, including those associated with reproduction, as well as bone, liver, heart, and brain. In human tissues, isoflavones can have totally opposite effects – they can either mimic estrogen or block
Soy is a controversial food that has been widely studied for its estrogenic as well as anti-estrogenic effects on the body. Proponents claim that soy can tame hot flashes, prevent osteoporosis, and protect against hormonal cancers. Opponents worry that it may actually increase the risk of cancer, cause thyroid problems, and other health issues.
Up to now, there is yet concrete conclusions about soy, but it is probably due to the wide variation in how the studies have been designed – the types of soy used (fermented vs. unfermented), quantity consumed, and duration of exposure (since childhood vs. adulthood). That said, Asian populations have eaten a traditional diet of fermented soy for thousands of years and have reported a neutral to beneficial effect on many health conditions.
Average Isoflavone Intake in Asia is 25-50 mg/day.
Fermented Soy Foods_______Serving Size____Isoflavone content (mg)
Tempeh, cooked_____________3 oz_____________30
Soy sauce__________________1 Tsbp.___________0.02
Excessive estrogen stimulates the growth and multiplication of breast cancer cells. So it was once thought that soy foods increase the risk of breast cancer because soy contains isoflavones that may mimic our estrogen.
However, it has also been suggested that the lower risk of breast cancer in Asian countries compared to Europe, North America, and Australia/New Zealand is attributed to a lifelong intake of traditional soy foods. So who is right?
So far studies have not provided a clear-cut answer. Some have shown a slight benefit while others show no association. Nonetheless, no research has demonstrated that soy causes breast cancer, even in women who have had the cancer before. In fact, it appears that soy may have a mild estrogen-blocking action in breast tissues, resulting in a slight reduction of breast cancer risk and recurrence of breast cancer.
In addition, the protective effect seems to be more pronounced for women who start eating soy early in life. Women from Asian countries generally start consuming fermented soy foods found in traditional Asian diets at an early age. Fermented soy contains healthy bacteria that can convert isoflavone daidzein to equol. Equol is believed to block potentially negative effects of estrogen. Studies found that 50-60% of adults in Asia possess the equol-producing gut bacteria compared to only 25-30% of adults in Western countries. This may also explain why women from Asia who eat fermented soy seem to derive more benefits than Western women who generally consume unfermented, processed soy.
See also; The Good And Bad About Soy ”first part”
In theory, the potential estrogenic effects of soy isoflavones could help to tame hot flashes and night sweats that accompany menopause by giving an estrogen-like boost during a time of dwindling estrogen levels. Hence, soy has been a popular alternative treatment though it is not clearly supported by research which shows conflicting results. Nonetheless, in Asian countries where fermented soy is eaten daily, women do report lower rates of menopausal symptoms (10-20%) compared to women in the U.S. (70-80%).
Memory and Cognitive Function
Menopause has been linked with mood changes and memory impairment. Low levels of estrogen in women can reduce the number of estrogen receptors in the brain that are necessary for cognitive functions like memory and learning. The soy isoflavone daidzein has been hypothesized to reduce cognitive decline. Unfortunately, trials have yielded contradictory results with some showing benefits and others no benefit.
Endometrial (Uterine) Cancer
It is thought that the development of endometrial cancer could be related to prolonged exposure to unopposed estrogen, i.e., estrogen not counterbalanced with the hormone progesterone. Excess estrogen relative to progesterone may result in endometrial thickening and ultimately, endometrial cancer. A number of studies have examined whether high intakes of soy with anti-estrogenic activity in uterine tissue could be associated with a lower risk of endometrial cancer. The results are inconclusive.