Soy is a HOT topic and is the source of a heated debate in the nutrition and health community...
Much of what is written about soy is sensationalism, exaggeration and twisted lies to get readership, period.
No, I am NOT going to apologize for saying it because it is TRUE! I am sick and tired of website owners, blog authors, and even the mainstream media using scare tactics to get readership! It is nothing more than a twist on research to write sensational titles and controversial, scary sounding information to make money!
So I am going to offer a little common sense along with a LONG list of scientific research rather than just make a bunch of random claims....
Reading most articles on soy you would think it was some insidious, super-natural bean with some crazy, comic book style gender bending super powers!
Let's get our feet back on the ground and see what the research REALLY says!
This article is NOT going to be short so you might want to go get yourself a nice iced- spearmint tea or if you are reading in the winter a nice piping hot cup of herbal tea because this is going to be long!
Soy is a HOT topic in nutrition these days, some people
believe it is a healthy, delicious food, while others think it will do anything
from cause mineral deficiencies to change your gender! What is the truth and what does the research
REALLY say!
I think it is important to understand that there is MONEY to
be made by making sensational claims.
Why? Because sensationalism goes
VIRAL!
If I just write nice little stories about how broccoli is
good for you, or how you should eat your leafy greens no one is really going to
care that much. It is more of a, yeah,
we know kind of thing. But if I write an
article claiming that soy will cause infertility and change your gender I've got
a heavy hitter! The more traffic I get
the more advertising money I get, the more ad revenue, the more sales
etc....... Sensationalism sells!
I've read through many of these soy articles and when I get
to the bottom, rarely do I find any links to research. I may find links to other articles on the
same subject but I just don't find links to research. Why, because there really isn't any research
that actually proves or validates the claims being made. This is so frustrating to me because people
believe this stuff. Some of it is even
found in articles from the New York Times and other 'reputable' media
outlets.
Let's look at the actual research to find the truth about soy!
I'm not interested in sensationalism, I am also not
interested in promoting a food if it is in fact harmful. Regardless of my dietary choices, I could
certainly create a healthy, soy-free plant based diet if I found soy to be
an unhealthy or health damaging
food. I have no ties to any industry, I
don't sell soy or soy supplements I have absolutely no reason to promote soy as
healthy or not.
Myth #1 Soy Estrogens wreak havoc on your hormonal balance and cause
estrogen dominance, infertility and feminization of boys......etc.
This is the one claim that scares most people. It is scary to think that something could
affect your hormonal balance, but does soy really do this? First, a little common sense here. Does soy have the same reproductive system as
you? NO.
It is a plant.
There are three forms of estrogen found in the human body,
estradiol, estriol and estrone. In different
stages of life the level of these forms of estrogen change. The most active estrogen in the human body before
menopause is estradiol. Estradiol has
about 80 times greater potency than estriol and 12 times stronger than
estrone.
As you can see, endogenous, or estrogens made inside the
human body, have varying degrees of potency.
It is important to note here
that:
Phyto-estrogens are 100,000 TIMES weaker than estradiol!
Phytoestrogens have been found to be 1/100th to 1/1000th the
strength of estradiol. Phytoestrogens
have been found in research to either have very
mild pro-estrogenic activity OR mild anti-estrogenic activity. 1 I have explained in many nutrition classes
that phyto-estrogens have a very weak effect on estrogen receptors, therefore
they can have a more balancing effect rather than as powerful of an effect as
sensationalists claim.
If a woman has high estrogen levels, the WEAKER
phyto-estrogens will bind with receptor sites in place of some of the body's
significantly more powerful estrogens and actually LOWER estrogen levels.
In menopause, where estrogen levels are decreasing and changing
these weak phyto-estrogens can bind with otherwise empty receptor sites and
exert a weak estrogenic effect thereby easing menopausal symptoms.
It is important to understand the difference between a
steroidal form of estrogen and its powerful effect on the body, and a PLANT
estrogen that is very weak in comparison.
These weak phyto-estrogens DO NOT have the ability to do what these
sensational articles claim they are doing.
To explain in more technical terms I will quote an article
in US Pharmacist:
"Current
research suggests that phytoestrogens may be natural selective estrogen
receptor modulators (SERMs),8 which means that they can bind to certain estrogen receptors
in some tissues, either activating or down-regulating cellular responses.
The estrogen response system consists of two forms of the estrogen receptor
(ER-alpha), prominent in breast and uterine tissue, and (ER-beta) activate
cardioprotective and bone-stabilizing metabolic processes. Numerous
coregulators act in concert to regulate the transcriptional machinery of
cells sensitive to estrogenic compounds. As a result, depending on
concentrations of endogenous estrogens, as well as on which receptor
complexes are activated or down-regulated, SERMs can have either estrogenic
or anti-estrogenic effects.
Simultaneously, the
phytoestrogens appear to down-regulate the activity of the alpha-type
estrogen receptors (ER alpha) prominent in breast and uterine tissue. This
is one possible mechanism behind their proposed anticancer effects.
In addition,
accumulating evidence suggests that phytoestrogens can favorably affect the
balance of estrogen metabolites in the body. "Bad" metabolites
(16 alpha-hydroxyestrone, 4-hydroxyestrone and 4-hydroxyestradiol) are
genotoxic and mutagenic. The ratio of "good"
(2-hydroxyestrone) to "bad" metabolites is increasingly being
used as a marker to assess cancer risk. Non-ER–mediated effects on growth regulation
in human breast cancer cells have also been documented for phytoestrogens
role in these disease."2
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When we begin to review the scientific literature on soy, we
start to see that soy does NOT have the potency to cause significant estrogenic
activity. There are three different types of phyto-estrogens known at this time
and they include: coumestans, isoflavones, lignans and phenolic
phytoestrogens. These different types of
phyto-estrogens are found in a wide variety of plant foods, soy has become the subject
of much debate however, it is not even the plant with the highest
concentrations, more on that later.
What about the NATURALLY occuring hormones in Cow's Milk?
This is where things start to get interesting and also where
I think a lot of this demonizing of soy is coming from. Scare everyone about soy so they won't pay
attention to the fact that cow's milk contains NATURALLY occuring steroidal
hormones!
Before I cite the research I want to mention that this study
was done by The American Dairy Science Association so of course they downplay
the importance of estrogen compounds found in milk but I think it is extremely
important for people to understand that they are consuming bio-active steroidal
hormones that occur naturally in milk and this was a study on RAW organic milk
as well!!!
Yep, RAW organic milk contains estradiol and estrone, two bio-active steroidal hormones also found in humans!
I will quote the conclusion exactly as stated in the study: "Organic
and conventional dairy products did not
have substantially different concentrations of E1 [estrone] and E2
[beta-estradiol]. My point in quoting
this is that cow's milk NATURALLY contains the exact same potent estrogens as
the human body and they will have the same potency when binding to estrogen
receptors in the body, whereas phyto-estrogens do not!
This whole scare about phyto-estrogens and hormonal balance
seems a bit silly to me.
We run around
scared of a weak phytoestrogen and yet we completely ignore the most powerful
source of bio-active estrogens in our diet....MILK!
Okay, so if you still aren't convinced
that these phytoestrogens are not the demon they are portrayed to be, don't
take my word for it, let's look at the research available:
A study published in Menopause in 2000 found, " No
soy-related changes were observed on vaginal cytology, endometrial thickness,
uterine artery pulsatility index, or metabolic and hormonal parameters tested." The study went on to conclude that soyselect
may be a safe and effective treatment of hot flashes in menopausal women.3
A study published in Nutrition and Cancer in 1999 looked at
soy intake and its effect on sex hormone metabolism. The conclusion of this study: " Thus soy
consumption had no significant effect on the menstrual cycle, serum sex
hormones, or urinary estrogen metabolite ratio in premenopausal OC [oral
contraceptive] users or non-OC users."4
A study published in 2002 on the effect of soy protein on
endogenous hormones in post-menopausal women reported: " This study does
not provide evidence that long-term ingestion of soy protein alters steroid
hormone values, but it suggests that soy protein may have small effects on
thyroid hormone values that are unlikely
to be clinically important."5 [emphasis mine]
A study published in Metabolism in 2000 looked at soy
protein foods on oxidized LDL levels as well as ex vivo hormone receptor
activity and concluded: " consumption of high-isoflavone foods was
associated with reduced levels of
circulating oxidized LDL even in subjects taking vitamin E, with no evidence of increased urinary
estrogenic activity. Soy consumption may reduce cardiovascular disease
risk without increasing the risk for hormone-dependent cancers."6
Another study entitiled "Modest Hormonal Effects of Soy
Isoflavones in Postmenopausal Women" : Set out to study the hormonal effects
of soy phytoestrogens on post-menopausal women.
The conclusions in this study are slightly different than the others,
however, none of the small changes noted were deemed to be stastitically or
even physiologically significant. Their
conclusion: "The high-iso diet [high isoflavone] resulted in a small but
significant decrease in estrone-sulfate (E1-S), a trend toward lower estradiol
(E2) and estrone (E1), and a small but significant increase in SHBG [sex
hormone binding globulin]. For the other hormones, the few significant changes
noted were also small and probably not of physiological importance. There were
no significant effects of the low-iso or high-iso diets on vaginal cytology or
endometrial biopsy results. These data suggest that effects of isoflavones on
plasma hormones per se are not significant mechanisms by which soy consumption
may exert estrogen-like effects in postmenopausal women."7
There are many other studies that have similar conclusions
but I think you get the picture, soy isoflavones do not have a significant
effect on circulating hormones in women and certainly no negative effects were
seen.
But What About Men? Soy is bad for men right?
Mention the word SOY in a room full of men and watch them
all flee toward the nearest exit!! Soy
is scary to men, read the latest body building magazine or men's magazine and
you'd think we had discovered some freakish gender bending monster plant from
the dark side!
Is all this fear really scientifically justified?
Let's ignore all the sensational claims being made, all the
SCARY ideas being tossed around and get right to the science!
First up, a study published in the Journal of Nutrition in
2002 looked at the hormonal effects of soy in both men and women. You'd think with all the fear surrounding soy
that this study would find some crazy gender bending effect in men, or at least
a lowering of fertility right?
NOPE! The conclusion of this
study is not scary at all: "These
recent studies in men consuming soyfoods or supplements containing 40–70 mg/d
of soy isoflavones showed few effects on plasma hormones or semen quality.
These data do not support concerns about effects on reproductive hormones and
semen quality."8
But everyone says soy decreases testosterone and impairs
fertility in men? Yes, I know you have read articles in seeming 'reputable'
magazines, newspapers or maybe even
heard it on t.v. but you need to realize one thing....what does the media
need? They need an audience and the
bigger the audience, the bigger their profits!
The best way to achieve this.....use sensationalism. If you mention fertility or testosterone to
men every last one of them is going to read it!
They know this is the best way to get readership in men and the more
sensational the claims the better. Is it
true? No, but it sure gets readership. Let's keep going......
A meta-analysis published in Fertility and Sterility in 2010,
basically a review of the current scientific literature on soy protein and its
effect on reproductive hormones in men. This
is not the result of one study, this is an analysis of the available peer
reviewed research. What did the
researchers conclude as a result of this meta-analysis: " No significant effects of soy protein
or isoflavone intake on T [testosterone], SHBG [sex-hormone binding globulin],
free T [free testosterone], or FAI [free androgen index] were detected
regardless of statistical model. The results of this meta-analysis suggest that
neither soy foods nor isoflavone supplements alter measures of bioavailable T [testosterone]
concentrations in men."9
Soy reduces the risk of Prostate Cancer
Unfortunately among all the ridiculous, unsupported claims
about soy and male hormones and fertility the benefits of phyto-estrogens in
men are lost. Yes, soy has shown to have
beneficial effects in men, especially in reducing the risk of prostate cancer
by reducing PSA levels in men.
A study published in the Urology journal in 2004 looked at
the effects of phytoestrogens and their effect on PSA levels and sex hormones
in men with prostate cancer. Well, if
you've bought into the scare tactics used by many media outlets you may think
soy contributed to prostate cancer along with everything else they say soy
does, but you'd be wrong! This study
concluded: " The data from this study indicate that a daily diet
containing four slices of a bread rich in HT [heat treated] soy grits favorably
influences the PSA level and the free/total PSA ratio in patients with prostate
cancer. This work provides some evidence to support epidemiologic studies
claiming that male populations who consume high phytoestrogen diets have a
reduced risk of prostate cancer development and progression." 10
A study in 2006 published in the European Journal of
Clinical Nutrition looked at soy consumption and its subsequent effects on
testesterone levels as well as PSA levels as well. This study had a similar conclusion to the
studies before it: " A 14% decline
in serum PSA levels (P=0.10), but no change in testosterone (P=0.70), was
observed during the high soy diet in contrast to the low soy diet."
So yet again, we see that soy did not cause any decrease or
change in teststerone levels in men. The
majority of research available does NOT show that soy has any negative hormonal
effects on men.
So where are all these claims coming from?
There is an article in a journal that was
written about A SINGLE CASE where a man had been drinking ONE GALLON OF SOY
MILK PER DAY, along with any other soy that may have been in his diet and he
did have some effects including gynecomastia, the development of mammary tissue
in men.
As soon as the soymilk
consumption was reduced to a normal amount all of the negative effects
resolved.
This isolated and EXTREME case
is used to promote a whole slew of false information and because it was
published in some prestigious journal it must mean that soy intake in men is
bad!
There have been other ANIMAL
studies where MASSIVE doses of isolated isoflavones have been used to exert
negative effects in monkeys and other animals but again, these effects are not
seen in humans consuming normal or even high amounts of soy foods.
The information is being twisted and exaggerated and an
unsuspecting public is being misled to believe that somehow this is some
super-natural bean that has super powers that can wreak havoc on human
health.....it honestly is as humble and simple a bean as any other. But, if you still aren't convinced I will
continue on with the research in men...............
Another article in Nutrition and Cancer looked at soy milk
intake and serum sex hormone levels in British men. Unlike what you may expect, no gender
bending, super natural powers were seen in soy.
The researchers of this study concluded: " Soy milk intake was not
associated with serum concentrations of testosterone, free testosterone,
androstanediol glucuronide, sex hormone-binding globulin, or luteinizing
hormone. These results suggest that soy milk intake, as a marker of isoflavone
intake, is not associated with serum sex hormone concentrations among
free-living Western men."11
Okay, last research article on soy and male hormones......if
this doesn't allay your fears I really don't know what will.
This study looked at serum hormone levels and
soy milk consumption among Japanese men.
Serum estrone levels actually
DECREASED in the soy supplemented group and INCREASED over time in the
control group over time. The
researchers also concluded that none of the other hormones, including
testosterone changed significantly between the soy supplemented group or
control group. 12
The take home message here, consumption of organic non-GMO
of course tofu, tempeh, soy milk, edamame or other whole soy foods DOES NOT
have any negative hormonal effects in men, women, children, aliens etc...!~
*Okay maybe it does in aliens ;-)
What about Soy and
Thyroid Function?
Both medical doctors and alternative practitioners have a
tendency to spread nutrition information they read in the latest magazine or
'reputable' newspaper with little research into where the article came from or
what science supports the claims being made.
I have heard from clients who have told me some practitioner
told them their thyroid issues were caused by a diet too low in fat, some were
told their endometriosis was caused by eating too much edamame, the problem
with this is........well,
it IS NOT TRUE, period! I challenge either of these practitioners to
provide solid PROOF that this is actually the case!
These soy articles drive me up the wall because the fact is,
they each cite each other as a source but provide little scientific research to
support their claims and when they do cite research it is generally a study
done on animals on EXORBITANT amounts of isolated isoflavones that has NO real
life application and therefore is useless in terms of evaluating the effects of
the whole food in a human diet!
What DOES the research say about soy and thyroid?
A review published in the Thyroid journal in 2006 looked at
soy intake and its effect on hypothyroidism from 14 trials looking at soy
intake and at least one marker of thyroid function. This review of the current literature
concluded that: " However, hypothyroid
adults need not avoid soy foods. In addition, there remains a
theoretical concern based on in vitro and animal data that in individuals with
compromised thyroid function and/or whose iodine intake is marginal soy foods
may increase risk of developing clinical hypothyroidism. Therefore, it is
important for soy food consumers to make sure their intake of iodine is
adequate."13
In review, the researchers state that there is no evidence
to suggest an avoidance of soy food if you are hypothyroid. The important factor was to ensure adequate
iodine levels.
In another study in the Journal of Medicinal Food in 2007,
researchers looked at the effects of both seaweeds and soy on thyroid
function. Interestingly they found that
seaweed increased TSH levels, while soy did not. To quote the researchers conclusion: " Soy
supplementation did not affect thyroid end points. Seven weeks of 5 g/day
seaweed supplementation was associated with a small but statistically
significant increase in TSH. Soy protein isolate supplementation was not
associated with changes in serum thyroid hormone concentrations." 14
Another study in 2007 looked at soy isoflavone supplements
with varying levels of isoflavones to evaluate varying levels of intake and its
effect on thyroid function in healthy men.
Well, yet again researchers did not find any significant effect whether
low or high intake. The conclusion:
" Results of this study demonstrate that soy isoflavones in a protein
matrix do not significantly influence circulating thyroid hormones in healthy
young men." 15
The most important consideration in thyroid function and soy
consumption is merely to ensure that you have adequate iodine intake and other
than that regular soy consumption will not have any negative effect on thyroid
function.
What about Breast Cancer and Soy Consumption?
I want to be entirely thorough here because I know there are
A LOT of claims out there. Most of the
articles written merely say soy contains 'estrogens' therefore it is implicated
in all things related to 'estrogen.'
This is ridiculous! The majority
of research out there does not support ANY of the claims circulating around
about soy. I don't want you to merely take my word for it, because
that is what MOST other bloggers and writers out there expect you to do with
their sensational, albeit, FALSE claims.
Common sense tells me that any whole, plant based FOOD is
designed by nature to be beneficial, nutritious and healthy. But because of the smear campaign against
soy, we aren't going to even talk about common sense...just the science.
Did you know there are over 600 compounds in an orange that could KILL
you!
It's true! However,
they are in such minute amounts in an orange that you could never eat enough to
cause you any harm. But if someone
decided to have some vendetta against oranges for some reason they certainly
could use this information to cause a lot of fear. This is exactly what is happening with soy,
information is being twisted, misconstrued and exaggerated.
Researchers published a study in 2008 evaluating breast
cancer risks in association with soy consumption, they found that women
consuming 1 cup of soymilk per day or
1/2 cup of tofu daily had a 30% lower risk of breast cancer compared to
women with little to not soy products in their diet. 16
I'm not going to go into as much detail here on soy
consumption and breast cancer simply because if you read the portion of this
article with research showing that soy does not affect serum estrogen levels in
women it obviously makes sense that it is not going to affect breast cancer or
any other estrogen related health problems.
If you understand that cow's milk contains bio-active forms of estrogen
you know where the increases in estrogen actually come from.
Studies have shown though that the best protection soy
consumption has on breast cancer risk is when it is consumed early on in
life. Most breast cancer begins during
puberty and therefore early consumption has a greater effect on reducing the
risk of breast cancer. 17, 18
What about women who
already HAVE or Have Had breast cancer?
Medical doctors and their extremely POOR nutrition education
and understanding give a HUGE variation in recommendations when it comes to soy
and breast cancer. Some recommend
consumption, while others recommend against it. Unfortunately, doctors get their information
from the same place the public does and they are just as confused as the rest
of the population. If you think doctors
have time, or even care to review the current scientific literature you are
sorely mistaken.
What does the
science say:
A study published in 2009 in the Journal of the American
Medical Association actually showed that soy consumption could reduce the
recurrence of breast cancer. 19 This is not the only study that has
found a reduced risk of recurrence with soy intake, however, for the sake of
space I will only cite one more study just to solidify in your mind that soy
does not 'cause' or 'contribute' to breast cancer and it can actually be
beneficial to women who have had breast cancer.
The Shanghai Breast Cancer Survival Study included over
5,000 women and evaluated them over a 4 year period. During this time they evaluated consumption
of soy products and survival rates. The
researchers found that women who regularly consumed soy products such as soy
milk, tofu, or edamame had a 32% LOWER risk of recurrence and a 29% decreased
risk of death when compared to women with little or no soy intake.20
What about Inconsistent conclusions from research in the U.S.?
Researchers from this study also made the statement that the
inconsistent data on breast cancer and soy consumption in the U.S. is probably
due to the LOW intake of soy food among Americans!
This makes it more difficult to assess soy
intake and its effect on cancer when intake in the U.S. is so low.
I thought this was a very interesting
assessment by these researchers and I completely agree!
I would have to add to this that while soy intake is relatively low, dairy intake is HIGH and researchers CANNOT and/or DO NOT adjust for the estradiol and estrone estrogen compounds consumed in dairy products which could absolutely skew results!
What about Uterine Fibroids or Endometriosis and Soy Consumption?
I have known so many women with Uterine fibroids and their
solution always includes AVOIDING soy and other isoflavone containing foods and
this is a tragedy. Why? Because as we have seen before
phyto-estrogens are WEAK and in the case of excess estrogen they can actually
reduce estrogen levels thereby improving the situation rather than contributing
to it.
But again, don't take my word for it.......let's look at the
research.
A Japanese study found higher consumption of soy resulted in
reduced incidence of premenopausal hysterectomy for all causes. 21 When the women began this Japanese study NONE
of them had uterine fibroids or endometriosis which are the two main reasons
for hysterectomy. The reason this study
is important in looking at both endometriosis and uterine fibroids is the fact
that the women consuming higher amounts of soy had reduced risk of hysterectomy
indicating reduced incidence of common causes for hysterectomy. It is also important to look at the Japanese
studies here because in ALL of the U.S. studies researchers note that the soy
consumption among research participants remained low and dairy consumption in
the U.S. is HIGH. Researchers rarely
look at the connection between dairy consumption and female reproductive
disorders and so identifying soy's role is much more difficult in U.S.
populations.
A study in the British Journal of Nutrition looking at diet
and incidence of uterine fibroids researchers stated: " There was no significant association of intake of fats, soya isoflavones
or dietary fibre with uterine fibroids." 22
When research is cited it is also important to look at whether it
was conducted on animals, and if dietary intake or whole foods were used or if
isolated compounds were used. At times
researchers use isolates in levels significantly higher than would ever be
humanly possible to consume and this just does not provide accurate information
about real world consumption of these foods.
A study published in Epidemiology in 2007 looked at soy
consumption and the risk of endometriosis.
You may think that soy would
contribute to endometriosis, or hopefully if you've been reading this article
you have figured out by now that it doesn't but I'll quote the conclusion of
the researchers: " Dietary isoflavones may reduce the risk of
endometriosis among Japanese women."23.
They didn't say soy had no effect they concluded that soy
may REDUCE the risk of endometriosis!
Doesn't Soy Inhibit Mineral Absorption and cause mineral deficiencies?
Okay, I am addressing as many
claims about soy as I can so here is another.
This one seriously makes me laugh, I don't know why but it does, maybe
not more than the gender bender claims but it still makes me laugh. Most of the articles on this are so
exaggerated and sensational it seriously is hilarious to me, but maybe it
causes concern in others so I'll address it here, even though I personally don't
believe this even deserves acknowledgement at all
.
We will look at a study published
in 2011 in the Journal of Women's Health.
Most claims about soy and mineral status come from its phytate content,
if you want to know more about the
BENEFITS of phytate refer to my article on
legumes
HERE.
Researchers in this study wanted
to evaluate the effect of 2-3 servings of soy foods per day on mineral status
of premenopausal women. They took
baseline markers of iron and zinc status, bone markers, and thyroid hormones. Here are the results of this study and the
authors conclusions: " No significant changes were observed in bone
resorption, thyroidstimulating hormone (TSH), or free thyroxine after soy food intake. Incorporating ∼19 g soy protein from soy foods for 10 weeks had no
significant effect on iron or zinc status, bone resorption or formation, or
thyroid hormone status in premenopausal women.24
The actual research on soy consumption in relationship to
mineral status is actually small.
However, I have detailed the research of phytic acid in a previous
article
CLICK HERE.
I will summarize the information from that research:
phytic acid is a POTENT anti-cancer compound
and has been used and researched as a cancer treatment. It has NOT been found to affect mineral
status and in fact, is contained in plants to PREVENT mineral toxicity. Iron for example is TOXIC in excess and so
having phytic acid or oxalic acid in plant foods is a mechanism by which plants
help our bodies REGULATE absorption preventing toxicity, whereas iron in from
myoglobin or hemoglobin in animal based foods cannot be regulated!
Meat also contains Estradiol and other steroid hormones
If you are one of those individuals interested in organic
foods, you understand the risk factors associated with 'added synthetic'
hormones in foods. However, what you
may not realize is that animal based
foods have NATURALLY occuring hormones!
An animal produces hormones, just like humans and those
hormones are found in their blood, tissues and fluids just as they are found in
humans as well. Of course, these
hormones are found in higher concentrations in animals given synthetic
hormones, but my focus is the naturally occuring hormones in meat.
There is little available research on this, as I'm sure it
is a sensitive subject to the entire animal agriculture industry. However, assessement of estradiol levels has
been done in what researchers called, "edible tissues" muscle, liver
and kidney.25 I'm not going to pay for the article
to find out the results as I'm not really concerned with that, my overall point
is, steroidal, bio-active, potent hormones are found in ALL animal fluids and
tissues consumed by humans, regardless of whether or not they are organic. Increased consumption of meat has ocurred due
to concentrated farming of animals and this has NOT been good for the animals,
or human health.
Consumption of meat at our current level REQUIRES
concentrated feedlot operations, Period!
This whole organic, pasture raised idea does not remove exogenous
consumption of bovine hormones or other animal based hormones from our diet. These hormones are 100,000 times more potent
than phyto-estrogens even though we may be consuming them in much lower
quantities and yet we reasearch the effect of plant-phytoestrogens in relation
to human hormone balance but scant evidence of animal sources of estrogens and
its effect on humans is available. I'll
let you draw your own conclusions as to why this is.
All I will say is look at my right hand while
I reach in your pocket with my left. A
mere distraction from something much worse underneath the surface.
What food is highest in phyto-estrogens, and is soy the only food that
contains phytoestrogens?
Here again we have this demonizing of soy for its
phytoestrogen content and then everyone says, Eat FLAX it is good for you! Flax is good for you and so is whole soy but
this is where the story gets even MORE twisted!
If you thought SOY was the highest in phytoestrogens......think again!
Flax.....................379,380 ug/100g
Soy......................103,920 ug/100g
Okay, I am going to stop here for a second.
Flax has MORE than DOUBLE the amount of phyto-estrogens as soy!
What is up with this, flax is good for you but soy is BAD
because of its phytoestrogens and yet flax has more than double the amount of
phytoestrogens. Yes, there are different
kinds of phytoestrogen but seriously, this makes no sense to me.26 Lets go on............
Sesame seeds...........8008
Multi-grain bread.......4798
garlic.........................603
Dried apricots.............444
Dates........................329
Sunflower seeds.........216
Olive oil.....................180
Almonds....................131
Green Beans..............105
Onion.........................32
I realize that flax and soy have SIGNIFICANTLY higher levels
of phytoestrogens than other foods, however, nearly ALL plant foods have some
level of phytoestrogens. You can't avoid
them, and they are not harmful.
Hopefully this has helped you understand that consumption of
whole non-GMO soy foods is not harmful and is not going to cause any health
problems.
If there are other concerns, aside from GMO soy that you
come across don't hesistate to ask and I will certainly do some research and
help answer your questions.
Resources:
1.
http://www.athena-urology.com/patient-docs/Phytoestrogen.pdf
2.
http://www.uspharmacist.com/content/d/health%20systems/c/10174/
3.
Menopause (New York, N.Y.) [2000, 7(2):105-11]
4.
Margaret C. Martini,
Betsy B. Dancisak, Carol J. Haggans, William Thomas & Joanne L. Slavin
(2009). Effects of Soy Intake on Sex Hormone
Metabolism in Premenopausal Women. Nutrition and Cancer,34(2), 133-139.
5. Victoria W Persky, Mary E Turyk, Ling Wang, Sally Freels, Robert
Chatterton, Jr, Stephen Barnes, John Erdman, Jr, Daniel W Sepkovic, H Leon Bradlow and Susan Potter (2002). Effect of soy protein on
endogenous hormones in postmenopausal women.American Journal of Clinical Nutrition
6. http://www.sciencedirect.com/science/article/pii/S0026049500800220
7.
http://jcem.endojournals.org/content/84/10/3479.short
8.
http://jn.nutrition.org/content/132/3/570S.short
9.
http://www.sciencedirect.com/science/article/pii/S001502820900
6
10.
http://www.sciencedirect.com/science/article/pii/S0090429504004364
11.
http://www.tandfonline.com/doi/abs/10.1080/01635581.2001.9680610
12.
http://cebp.aacrjournals.org/content/10/3/179.short
13.
Mark
Messina and Geoffrey Redmond. Thyroid. March 2006, 16(3): 249-258.
doi:10.1089/thy.2006.16.249.
14.
Jane Teas, Lewis E. Braverman, Mindy S. Kurzer,
Sam Pino, Thomas G. Hurley, and James R. Hebert. Journal of Medicinal Food.
March 2007, 10(1): 90-100. doi:10.1089/jmf.2005.056.
15.
Barbara L. Dillingham, Brianne L. McVeigh,
Johanna W. Lampe, and Alison M. Duncan. Thyroid. February 2007, 17(2): 131-137.
doi:10.1089/thy.2006.0206.
16.
Wu AH, Yu MC, Tseng CC, Pike MC.
Epidemiology of soy exposures and breast cancer risk. Br J Cancer 2008;98:9-14.
17.
Korde LA, Wu AH, Fears T, et al.
Childhood soy intake and breast cancer risk in Asian American women. Cancer
Epidemiol Biomarkers Prev 2009;18:OF1-10.
18.
Shu XO, Jin F, Dai Q, et al. Soyfood
intake during adolescence and subsequent risk of breast cancer among Chinese
women. Cancer Epidemiol Biomarkers Prev. 2001;10:483-8.
19.
Shu XO, Zheng Y, Cai H, et al. Soy
food intake and breast cancer survival. JAMA. 2009;302:2437-2443.
20.
Ballard-Barbash R, Neuhouser ML.
Challenges in design and interpretation of observational research on health
behaviors and cancer survival. JAMA. 2009;302:2483-2484.
21.
Nagata C, Takatsuka N, Kawakami N,
Shimizu H. Soy product intake and premenopausal hysterectomy in a follow-up
study of Japanese women. Eur J Clin Nutr 2001:55:773-7.
22.
http://www.ncbi.nlm.nih.gov/pubmed/19459228
23.
http://www.ncbi.nlm.nih.gov/pubmed/17474167
24.
http://www.ncbi.nlm.nih.gov/pubmed/21486162
25.
http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0463.2001.tb05788.x/abstract
26.
http://www.dietaryfiberfood.com/phytoestrogen-hormones/phytoestrogen-food-sources.php