Extremely interesting and informative article. Discusses the importance
of fermented soy, estrogen dominance from soy and that flax seed has
components similar to soy.

Source: http://www.drlam.com/opinion/print/soyandestrogen.htm

Soy and Estrogen Dominance

In the last ten years, Soy has gone from an obscure food to the perfect
food. Promoters of soy products would like you to believe that next to
water, soy is probably one of the healthiest foods you can eat.

Based on soy's extensive history of consumption in the Asian diet and
the long lifespan of Asians as a group, soy industry has been
successfully promoted soy as a family tradition and key to longevity
and good health. However, careful scrutiny shows that the Asian diet is
not one that is focused on soy at all. In fact 65% of the calories from
a Japanese diet comes from fish. In China, 65% of calories come from
pork. The total caloric intake from soy in the Chinese diet is only
1.5%. The amount of soy consumed in Asia averages only 2 teaspoons a
day and up to ¼ cup in some parts of Japan. This is certainly not the
large amount that we were led to believe. Furthermore, the modern
processed soy protein food in the form of soy burgers and soy drinks
found in supermarkets in no way resembles the traditional Asian soy.
Soy consists of complex chemical and structural components. The main
components are protein, essential fatty acids, as well as a class of
compounds known as isoflavones. Isoflavones as a family include
compounds such as genistein, daidzein, equol, and glycitein. These are
also called phytoestrogens in that they have properties that are
estrogen like but are derived from plants. The amount of genistein per
day consumed in the average Japanese is only 10mg. Mega consumption of
isoflavones such as soy burgers can bring the total daily genistein
intake to over 200mg. Genistein is particularly harmful for people who
have preexisting low or marginally low thyroid function. It's
antagonism to the thyroid hormone is well established. A daily dose of
genistein as low as 30mg can affect normal thyroid function.

The soy isoflavone genistein and daidzein are similar to 17
beta-estradiols, but are 100,000 times weaker in estrogenic activity
and are therefore weak estrogens. Although these isoflavones are weak
estrogens, people who eat a lot of it can have their blood level of
isoflavones as much as 10,000 times higher than those who do not
consume soy. Over time, high concentrations of isoflavones in the body
can have a significant cumulative estrogenic and toxic effect,
especially when they are exposed to organs that have sensitive estrogen
receptors sites such as the breast, uterus, and thyroid.

The Chinese and Japanese have known about the toxicity of soy for
centuries. Soy contains a variety of toxic chemicals, which cannot be
fully metabolized by the body, unless it undergoes a long cooking, or
fermentation process. Unfermented soy contains phylates, which acts as
an anti-nutrient and blocks the body's absorption of minerals from
the gastro intestinal track. It also contains enzymes inhibitors that
reduce protein digestion. Processed soy protein contains carcinogens
such as nitrates, lysinoalanine, as well as a large group of
anti-nutrients not found in traditional soy consumed in Asia. It also
lacks calcium and causes a deficiency of vitamin D, both of which are
not conducive for bone building.

The way soy is consumed in Asia is that it is allowed to be fermented
first for a long time, from 6 months to 3 years. Only after extensive
fermentation is soy being eaten as a condiment and not as a replacement
for animal food. Fermented soy includes miso, tempeh, and natto and
does not have the negative properties of unfermented soy. Miso is
widely used as a soup base in Japan. Natto is a foul smelling fermented
soybean preparation that has been consumed in Japan for over 1,000
years. Natto also has a high concentration of vitamin K2, a critical
nutrient for bone building. It also has the extraordinary property of
dissolving blood clots and keeping our blood vessels clear.

Modern processed soy products, including soy burgers and soy cheese are
not the same as traditional Asian soy. They are by and large
unfermented and include tofu and soy protein. These do not provide the
same benefits as fermented soy products. A typical Japanese man eats
about 8 grams (2 teaspoon) a day of soy that is mostly fermented as
compared to the 220 grams (8oz) a western person in the form of a chunk
of tofu and 2 glasses of soy milk, both of which are unfermented.
Eating unfermented soy by a vegetarian actually increases the risk of
mineral deficiency including calcium, magnesium, copper, and zinc.
Unfermented soy such as soymilk is also the second most common
allergen. 1% of the population is truly allergic to cow's milk, and
2/3 of those will be intolerant to soymilk. Soymilk is also high in
aluminum, because they are processed in large aluminum tanks. Studies
have shown that 30gram of unfermented soy consumed daily can affect
thyroid function and is strongly linked to a host of auto immune
diseases such as Hashimoto's thryoiditis as well as hypothyroidism.

There are some studies have shown that taking 35-60 gram of soy protein
a day containing aromatase inhibitor genistein can protect the body
against breast cancer. Other studies have shown that women eating soy
had a higher incidence of changes in their bodily cellular structure
consistent with per-malignant such as epithelial hyperplasia. Whether
soy is beneficial or detrimental to those with estrogen dominance is
highly controversial. The key to the puzzle is to understand that
phytoestrogens are widely distributed in plants and have structures
quite similar to the estrogen in our bodies. As such, they can bind
weakly to our body's internal estrogen receptor sites. Because
estrogen is involved in the development of many unwanted disease
including hormone sensitive cancers such as breast cancer, it is
important to keep the estrogen level as low as possible in the body.
Exposure to the estrogenic effect from soy, though weak, should be
avoided in those who are at risk or , have symptoms of , or are in an
estrogen dominance state.

Fortunately, flax seed also contains compounds that are structurally
similar to the phyto-estrogen of soy. Enterolactone and enterodiol from
flax seeds are structurally similar to the phyto-estrogen and daidzein
from soy. This closeness suggests that flax seed may interfere with
estrogen metabolism through competitive binding of the receptor sites.
Studies have shown that supplementing the diet with 1oz of ground flax
seed but not with 1 oz of soy flour significantly alters the estrogen
metabolism in the body. The end result is that there is a favoring of
the less biologically active estrogen metabolites (2OHE1) in
postmenopausal women. To avoid the negative properties of unfermented
soy, it is wise to replace it with freshly ground flaxseeds so that the
body can receive the beneficial phyto-estrogenic effect of unfermented
soy while avoiding its anti-nutrient properties. Choose flaxseed that
is grown in cold climate such as Canada. Flaxseed also is a good source
of omega-3 fatty acid but it has a tendency to turn rancid rather
quickly and takes second place when compared to fish oil as a source of
omega-3 fatty acid.