14 Ağustos 2012 Salı

Soy consumption myths, truths, and sensationalism!

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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 peoplebelieve it is a healthy, delicious food, while others think it will do anythingfrom cause mineral deficiencies to change your gender!  What is the truth and what does the researchREALLY say!
I think it is important to understand that there is MONEY tobe made by making sensational claims. Why?  Because sensationalism goesVIRAL!


If I just write nice little stories about how broccoli isgood for you, or how you should eat your leafy greens no one is really going tocare that much.  It is more of a, yeah,we know kind of thing.  But if I write anarticle claiming that soy will cause infertility and change your gender I've gota heavy hitter!  The more traffic I getthe more advertising money I get, the more ad revenue, the more salesetc.......  Sensationalism sells!


I've read through many of these soy articles and when I getto the bottom, rarely do I find any links to research.  I may find links to other articles on thesame subject but I just don't find links to research.  Why, because there really isn't any researchthat actually proves or validates the claims being made.  This is so frustrating to me because peoplebelieve this stuff.  Some of it is evenfound in articles from the New York Times and other 'reputable' mediaoutlets. 
Let's look at the actual research to find the truth about soy!I'm not interested in sensationalism, I am also notinterested in promoting a food if it is in fact harmful.  Regardless of my dietary choices, I couldcertainly create a healthy, soy-free plant based diet if I found soy to bean  unhealthy or health damagingfood.  I have no ties to any industry, Idon't sell soy or soy supplements I have absolutely no reason to promote soy ashealthy or not.

Myth #1 Soy Estrogens wreak havoc on your hormonal balance and causeestrogen dominance, infertility and feminization of boys......etc.


This is the one claim that scares most people.  It is scary to think that something couldaffect your hormonal balance, but does soy really do this?  First, a little common sense here.  Does soy have the same reproductive system asyou?  NO. It is a plant.    There are three forms of estrogen found in the human body,estradiol, estriol and estrone.  In differentstages of life the level of these forms of estrogen change.  The most active estrogen in the human body beforemenopause is estradiol.  Estradiol hasabout 80 times greater potency than estriol and 12 times stronger thanestrone.  As you can see, endogenous, or estrogens made inside thehuman body, have varying degrees of potency.  It is important to note herethat:
Phyto-estrogens are 100,000 TIMES weaker than estradiol!
Phytoestrogens have been found to be 1/100th to 1/1000th thestrength of estradiol.   Phytoestrogenshave been found in research to either have very mild pro-estrogenic activity OR mild anti-estrogenic activity. 1  I have explained in many nutrition classesthat phyto-estrogens have a very weak effect on estrogen receptors, thereforethey can have a more balancing effect rather than as powerful of an effect assensationalists claim.If a woman has high estrogen levels, the WEAKERphyto-estrogens will bind with receptor sites in place of some of the body'ssignificantly more powerful estrogens and actually LOWER estrogen levels.
In menopause, where estrogen levels are decreasing and changingthese weak phyto-estrogens can bind with otherwise empty receptor sites andexert a weak estrogenic effect thereby easing menopausal symptoms.
It is important to understand the difference between asteroidal form of estrogen and its powerful effect on the body, and a PLANTestrogen that is very weak in comparison. These weak phyto-estrogens DO NOT have the ability to do what thesesensational articles claim they are doing.
To explain in more technical terms I will quote an articlein 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

When we begin to review the scientific literature on soy, westart to see that soy does NOT have the potency to cause significant estrogenicactivity. There are three different types of phyto-estrogens known at this timeand they include: coumestans, isoflavones, lignans and phenolicphytoestrogens.  These different types ofphyto-estrogens are found in a wide variety of plant foods, soy has become the subjectof much debate however, it is not even the plant with the highestconcentrations, more on that later.
What about the NATURALLY occuring hormones in Cow's Milk?
This is where things start to get interesting and also whereI think a lot of this demonizing of soy is coming from.  Scare everyone about soy so they won't payattention to the fact that cow's milk contains NATURALLY occuring steroidalhormones!

Before I cite the research I want to mention that this studywas done by The American Dairy Science Association so of course they downplaythe importance of estrogen compounds found in milk but I think it is extremelyimportant for people to understand that they are consuming bio-active steroidalhormones that occur naturally in milk and this was a study on RAW organic milkas 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: "Organicand conventional dairy products did nothave substantially different concentrations of E1 [estrone] and E2[beta-estradiol].  My point in quotingthis is that cow's milk NATURALLY contains the exact same potent estrogens asthe human body and they will have the same potency when binding to estrogenreceptors in the body, whereas phyto-estrogens do not!
This whole scare about phyto-estrogens and hormonal balanceseems a bit silly to me. 

We run aroundscared of a weak phytoestrogen and yet we completely ignore the most powerfulsource of bio-active estrogens in our diet....MILK!   
Okay, so if you still aren't convincedthat these phytoestrogens are not the demon they are portrayed to be, don'ttake my word for it, let's look at the research available:
A study published in Menopause in 2000 found, " Nosoy-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 soyselectmay be a safe and effective treatment of hot flashes in menopausal women.3

A study published in Nutrition and Cancer in 1999 looked atsoy intake and its effect on sex hormone metabolism.  The conclusion of this study: " Thus soyconsumption had no significant effect on the menstrual cycle, serum sexhormones, or urinary estrogen metabolite ratio in premenopausal OC [oralcontraceptive] users or non-OC users."4
A study published in 2002 on the effect of soy protein onendogenous hormones in post-menopausal women reported: " This study doesnot provide evidence that long-term ingestion of soy protein alters steroidhormone values, but it suggests that soy protein may have small effects onthyroid hormone values that are unlikelyto be clinically important."5 [emphasis mine]
A study  published in Metabolism in 2000 looked at soyprotein foods on oxidized LDL levels as well as ex vivo hormone receptoractivity and concluded: " consumption of high-isoflavone foods wasassociated with reduced levels ofcirculating oxidized LDL even in subjects taking vitamin E, with no evidence of increased urinaryestrogenic activity. Soy consumption may reduce cardiovascular diseaserisk without increasing the risk for hormone-dependent cancers."6

Another study entitiled "Modest Hormonal Effects of SoyIsoflavones in Postmenopausal Women" :  Set out to study the hormonal effectsof 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 oreven physiologically significant.  Theirconclusion: "The high-iso diet [high isoflavone] resulted in a small butsignificant decrease in estrone-sulfate (E1-S), a trend toward lower estradiol(E2) and estrone (E1), and a small but significant increase in SHBG [sexhormone binding globulin]. For the other hormones, the few significant changesnoted were also small and probably not of physiological importance. There wereno significant effects of the low-iso or high-iso diets on vaginal cytology orendometrial biopsy results. These data suggest that effects of isoflavones onplasma hormones per se are not significant mechanisms by which soy consumptionmay exert estrogen-like effects in postmenopausal women."7
There are many other studies that have similar conclusionsbut I think you get the picture, soy isoflavones do not have a significanteffect on circulating hormones in women and certainly no negative effects wereseen.
But What About Men? Soy is bad for men right?


Mention the word SOY in a room full of men and watch themall flee toward the nearest exit!!  Soyis scary to men, read the latest body building magazine or men's magazine andyou'd think we had discovered some freakish gender bending monster plant fromthe dark side!

Is all this fear really scientifically justified?
Let's ignore all the sensational claims being made, all theSCARY ideas being tossed around and get right to the science!
First up, a study published in the Journal of Nutrition in2002 looked at the hormonal effects of soy in both men and women.  You'd think with all the fear surrounding soythat this study would find some crazy gender bending effect in men, or at leasta lowering of fertility right? NOPE!  The conclusion of thisstudy is not scary at all:  "Theserecent studies in men consuming soyfoods or supplements containing 40–70 mg/dof soy isoflavones showed few effects on plasma hormones or semen quality.These data do not support concerns about effects on reproductive hormones andsemen quality."8
But everyone says soy decreases testosterone and impairsfertility in  men?  Yes, I know you  have read articles in seeming 'reputable'magazines,  newspapers or maybe evenheard it on t.v. but you need to realize one thing....what does the medianeed?  They need an audience and thebigger the audience, the bigger their profits! The best way to achieve this.....use sensationalism.  If you mention fertility or testosterone tomen every last one of them is going to read it! They know this is the best way to get readership in men and the moresensational the claims the better.  Is ittrue?  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 itseffect on reproductive hormones in men.  Thisis not the result of one study, this is an analysis of the available peerreviewed research.  What did theresearchers conclude as a result of this meta-analysis:  " No significant effects of soy proteinor isoflavone intake on T [testosterone], SHBG [sex-hormone binding globulin],free T [free testosterone], or FAI [free androgen index] were detectedregardless of statistical model. The results of this meta-analysis suggest thatneither 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 claimsabout soy and male hormones and fertility the benefits of phyto-estrogens inmen are lost.  Yes, soy has shown to havebeneficial effects in men, especially in reducing the risk of prostate cancerby reducing PSA levels in men.

A study published in the Urology journal in 2004 looked atthe effects of phytoestrogens and their effect on PSA levels and sex hormonesin men with prostate cancer.  Well, ifyou've bought into the scare tactics used by many media outlets you may thinksoy contributed to prostate cancer along with everything else they say soydoes, but you'd be wrong!  This studyconcluded: " The data from this study indicate that a daily dietcontaining four slices of a bread rich in HT [heat treated] soy grits favorablyinfluences the PSA level and the free/total PSA ratio in patients with prostatecancer. This work provides some evidence to support epidemiologic studiesclaiming that male populations who consume high phytoestrogen diets have areduced risk of prostate cancer development and progression." 10

A study in 2006 published in the European Journal ofClinical Nutrition looked at soy consumption and its subsequent effects ontestesterone levels as well as PSA levels as well.  This study had a similar conclusion to thestudies before it:  " A 14% declinein serum PSA levels (P=0.10), but no change in testosterone (P=0.70), wasobserved during the high soy diet in contrast to the low soy diet." 
So yet again, we see that soy did not cause any decrease orchange in teststerone levels in men.  Themajority of research available does NOT show that soy has any negative hormonaleffects on men. 

So where are all these claims coming from?   
There is an article in a journal that waswritten about A SINGLE CASE where a man had been drinking ONE GALLON OF SOYMILK PER DAY, along with any other soy that may have been in his diet and hedid have some effects including gynecomastia, the development of mammary tissuein men.  As soon as the soymilkconsumption was reduced to a normal amount all of the negative effectsresolved.  This isolated and EXTREME caseis used to promote a whole slew of false information and because it waspublished in some prestigious journal it must mean that soy intake in men isbad!  There have been other ANIMALstudies where MASSIVE doses of isolated isoflavones have been used to exertnegative effects in monkeys and other animals but again, these effects are notseen in humans consuming normal or even high amounts of soy foods. 

The information is being twisted and exaggerated and anunsuspecting public is being misled to believe that somehow this is somesuper-natural bean that has super powers that can wreak havoc on humanhealth.....it honestly is as humble and simple a bean as any other.  But, if you still aren't convinced I willcontinue on with the research in men...............
Another article in Nutrition and Cancer looked at soy milkintake and serum sex hormone levels in British men.  Unlike what you may expect, no genderbending, super natural powers were seen in soy. The researchers of this study concluded: " Soy milk intake was notassociated with serum concentrations of testosterone, free testosterone,androstanediol glucuronide, sex hormone-binding globulin, or luteinizinghormone. These results suggest that soy milk intake, as a marker of isoflavoneintake, is not associated with serum sex hormone concentrations amongfree-living Western men."11
Okay, last research article on soy and male hormones......ifthis doesn't allay your fears I really don't know what will.  

This study looked at serum hormone levels andsoy milk consumption among Japanese men. Serum estrone levels actuallyDECREASED in the soy supplemented group and INCREASED over time in thecontrol group over time.   Theresearchers also concluded that none of the other hormones, includingtestosterone changed significantly between the soy supplemented group orcontrol group. 12
The take home message here, consumption of organic non-GMOof course tofu, tempeh, soy milk, edamame or other whole soy foods DOES NOThave any negative hormonal effects in men, women, children, aliens etc...!~
*Okay maybe it does in aliens ;-)
What about Soy andThyroid Function?


Both medical doctors and alternative practitioners have atendency to spread nutrition information they read in the latest magazine or'reputable' newspaper with little research into where the article came from orwhat science supports the claims being made. I have heard from clients who have told me some practitionertold them their thyroid issues were caused by a diet too low in fat, some weretold their endometriosis was caused by eating too much edamame, the problemwith this is........well,

it IS NOT TRUE, period!  I challenge either of these practitioners toprovide 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 tosupport their claims and when they do cite research it is generally a studydone on animals on EXORBITANT amounts of isolated isoflavones that has NO reallife application and therefore is useless in terms of evaluating the effects ofthe 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 atsoy intake and its effect on hypothyroidism from 14 trials looking at soyintake and at least one marker of thyroid function.  This review of the current literatureconcluded that: " However, hypothyroidadults need not avoid soy foods. In addition, there remains atheoretical concern based on in vitro and animal data that in individuals withcompromised thyroid function and/or whose iodine intake is marginal soy foodsmay increase risk of developing clinical hypothyroidism. Therefore, it isimportant for soy food consumers to make sure their intake of iodine isadequate."13

In review, the researchers state that there is no evidenceto suggest an avoidance of soy food if you are hypothyroid.  The important factor was to ensure adequateiodine levels.

In another study in the Journal of Medicinal Food in 2007,researchers looked at the effects of both seaweeds and soy on thyroidfunction.  Interestingly they found thatseaweed increased TSH levels, while soy did not.  To quote the researchers conclusion: " Soysupplementation did not affect thyroid end points. Seven weeks of 5 g/dayseaweed supplementation was associated with a small but statisticallysignificant increase in TSH. Soy protein isolate supplementation was notassociated with changes in serum thyroid hormone concentrations." 14
Another study in 2007 looked at soy isoflavone supplementswith varying levels of isoflavones to evaluate varying levels of intake and itseffect on thyroid function in healthy men. Well, yet again researchers did not find any significant effect whetherlow or high intake.  The conclusion:" Results of this study demonstrate that soy isoflavones in a proteinmatrix do not significantly influence circulating thyroid hormones in healthyyoung men." 15
The most important consideration in thyroid function and soyconsumption is merely to ensure that you have adequate iodine intake and otherthan that regular soy consumption will not have any negative effect on thyroidfunction.
What about Breast Cancer and Soy Consumption?
I want to be entirely thorough here because I know there areA LOT of claims out there.  Most of thearticles written merely say soy contains 'estrogens' therefore it is implicatedin all things related to 'estrogen.' This is ridiculous!  The majorityof research out there does not support ANY of the claims circulating aroundabout soy.  I don't want  you to merely take my word for it, becausethat is what MOST other bloggers and writers out there expect you to do withtheir sensational, albeit, FALSE claims. 
Common sense tells me that any whole, plant based FOOD isdesigned by nature to be beneficial, nutritious and healthy.  But because of the smear campaign againstsoy, 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 KILLyou!
It's true!  However,they are in such minute amounts in an orange that you could never eat enough tocause you any harm.  But if someonedecided to have some vendetta against oranges for some reason they certainlycould 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 breastcancer risks in association with soy consumption, they found that womenconsuming 1 cup of soymilk per day or 1/2 cup of tofu daily had a 30% lower risk of breast cancer compared towomen with little to not soy products in their diet. 16
I'm not going to go into as much detail here on soyconsumption and breast cancer simply because if you read the portion of thisarticle with research showing that soy does not affect serum estrogen levels inwomen it obviously makes sense that it is not going to affect breast cancer orany other estrogen related health problems. If you understand that cow's milk contains bio-active forms of estrogenyou know where the increases in estrogen actually come from.
Studies have shown though that the best protection soyconsumption has on breast cancer risk is when it is consumed early on inlife.  Most breast cancer begins duringpuberty and therefore early consumption has a greater effect on reducing therisk of breast cancer. 17, 18

What about women whoalready HAVE or Have Had breast cancer?
Medical doctors and their extremely POOR nutrition educationand understanding give a HUGE variation in recommendations when it comes to soyand breast cancer.  Some recommendconsumption, while others recommend against it.  Unfortunately, doctors get their informationfrom the same place the public does and they are just as confused as the restof the population.  If you think doctorshave time, or even care to review the current scientific literature you aresorely mistaken. 
What does thescience say:

A study published in 2009 in the Journal of the AmericanMedical Association actually showed that soy consumption could reduce therecurrence of breast cancer. 19   This is not the only study that hasfound a reduced risk of recurrence with soy intake, however, for the sake ofspace I will only cite one more study just to solidify in your mind that soydoes not 'cause' or 'contribute' to breast cancer and it can actually bebeneficial to women who have had breast cancer.

The Shanghai Breast Cancer Survival Study included over5,000 women and evaluated them over a 4 year period.  During this time they evaluated consumptionof soy products and survival rates.  Theresearchers found that women who regularly consumed soy products such as soymilk, tofu, or edamame had a 32% LOWER risk of recurrence and a 29% decreasedrisk 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 theinconsistent data on breast cancer and soy consumption in the U.S. is probablydue to the LOW intake of soy food among Americans!  This makes it more difficult to assess soyintake and its effect on cancer when intake in the U.S. is so low.  I thought this was a very interestingassessment 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 theirsolution always includes AVOIDING soy and other isoflavone containing foods andthis is a tragedy.  Why?  Because as we have seen beforephyto-estrogens are WEAK and in the case of excess estrogen they can actuallyreduce estrogen levels thereby improving the situation rather than contributingto it.

But again, don't take my word for it.......let's look at theresearch.

A Japanese study found higher consumption of soy resulted inreduced incidence of premenopausal hysterectomy for all causes. 21  When the women began this Japanese study NONEof them had uterine fibroids or endometriosis which are the two main reasonsfor hysterectomy.  The reason this studyis important in looking at both endometriosis and uterine fibroids is the factthat the women consuming higher amounts of soy had reduced risk of hysterectomyindicating reduced incidence of common causes for hysterectomy.  It is also important to look at the Japanesestudies here because in ALL of the U.S. studies researchers note that the soyconsumption among research participants remained low and dairy consumption inthe U.S. is HIGH.  Researchers rarelylook at the connection between dairy consumption and female reproductivedisorders and so identifying soy's role is much more difficult in U.S.populations.

A study in the British Journal of Nutrition looking at dietand incidence of uterine fibroids researchers stated: " There was no significant association of intake of fats, soya isoflavonesor dietary fibre with uterine fibroids." 22

When research is cited it is also important to look at whether itwas conducted on animals, and if dietary intake or whole foods were used or ifisolated compounds were used.  At timesresearchers use isolates in levels significantly higher than would ever behumanly possible to consume and this just does not provide accurate informationabout real world consumption of these foods.

A study published in Epidemiology in 2007 looked at soyconsumption and the risk of endometriosis. You  may think that soy wouldcontribute to endometriosis, or hopefully if you've been reading this articleyou have figured out by now that it doesn't but I'll quote the conclusion ofthe researchers:  " Dietary isoflavones may reduce the risk ofendometriosis among Japanese women."23.


They didn't say soy had no effect they concluded that soymay REDUCE the risk of endometriosis!
Doesn't Soy Inhibit Mineral Absorption and cause mineral deficiencies?
Okay, I am addressing as manyclaims about soy as I can so here is another. This one seriously makes me laugh, I don't know why but it does, maybenot more than the gender bender claims but it still makes me laugh.  Most of the articles on this are soexaggerated and sensational it seriously is hilarious to me, but maybe itcauses concern in others so I'll address it here, even though I personally don'tbelieve this even deserves acknowledgement at all
.We will look at a study publishedin 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 onlegumes HERE.

Researchers in this study wantedto evaluate the effect of 2-3 servings of soy foods per day on mineral statusof premenopausal women.  They tookbaseline markers of iron and zinc status, bone markers, and thyroid hormones.  Here are the results of this study and theauthors conclusions:  " No significant changes were observed in boneresorption, thyroidstimulating hormone (TSH), or free thyroxine after soy food intake.  Incorporating 19 g soy protein from soy foods for 10 weeks had nosignificant effect on iron or zinc status, bone resorption or formation, orthyroid hormone status in premenopausal women.24

The actual research on soy consumption in relationship tomineral status is actually small. However, I have detailed the research of phytic acid in a previousarticle CLICK HERE. 
I will summarize the information from that research: 

phytic acid is a POTENT anti-cancer compoundand has been used and researched as a cancer treatment.  It has NOT been found to affect mineralstatus and in fact, is contained in plants to PREVENT mineral toxicity.  Iron for example is TOXIC in excess and sohaving phytic acid or oxalic acid in plant foods is a mechanism by which plantshelp our bodies REGULATE absorption preventing toxicity, whereas iron in frommyoglobin 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 organicfoods, you understand the risk factors associated with 'added synthetic'hormones in foods.  However, what youmay  not realize is that animal basedfoods have NATURALLY occuring hormones!

An animal produces hormones, just like humans and thosehormones are found in their blood, tissues and fluids just as they are found inhumans as well.  Of course, thesehormones are found in higher concentrations in animals given synthetichormones, but my focus is the naturally occuring hormones in meat.

There is little available research on this, as I'm sure itis a sensitive subject to the entire animal agriculture industry.  However, assessement of estradiol levels hasbeen done in what researchers called, "edible tissues" muscle, liverand kidney.25  I'm not going to pay for the articleto find out the results as I'm not really concerned with that, my overall pointis, steroidal, bio-active, potent hormones are found in ALL animal fluids andtissues consumed by humans, regardless of whether or not they are organic.  Increased consumption of meat has ocurred dueto concentrated farming of animals and this has NOT been good for the animals,or human health.
Consumption of meat at our current level REQUIRESconcentrated feedlot operations, Period! This whole organic, pasture raised idea does not remove exogenousconsumption of bovine hormones or other animal based hormones from our diet.  These hormones are 100,000 times more potentthan phyto-estrogens even though we may be consuming them in much lowerquantities and yet we reasearch the effect of plant-phytoestrogens in relationto human hormone balance but scant evidence of animal sources of estrogens andits effect on humans is available.  I'lllet you draw your own conclusions as to why this is.

  All I will say is look at my right hand whileI reach in your pocket with my left.  Amere distraction from something much worse underneath the surface.
What food is highest in phyto-estrogens, and is soy the only food thatcontains phytoestrogens?
Here again we have this demonizing of soy for itsphytoestrogen content and then everyone says, Eat FLAX it is good for you!  Flax is good for you and so is whole soy butthis is where the story gets even MORE twisted!

If you thought SOY was the highest in phytoestrogens......think again!
Flax.....................379,380 ug/100gSoy......................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 BADbecause of its phytoestrogens and yet flax has more than double the amount ofphytoestrogens.  Yes, there are differentkinds of phytoestrogen but seriously, this makes no sense to me.26  Lets go on............
Sesame seeds...........8008Multi-grain bread.......4798garlic.........................603Dried apricots.............444Dates........................329Sunflower seeds.........216Olive oil.....................180Almonds....................131Green Beans..............105Onion.........................32
I realize that flax and soy have SIGNIFICANTLY higher levelsof phytoestrogens than other foods, however, nearly ALL plant foods have somelevel of phytoestrogens.  You can't avoidthem, and they are not harmful.

Hopefully this has helped you understand that consumption ofwhole non-GMO soy foods is not harmful and is not going to cause any healthproblems. 

If there are other concerns, aside from GMO soy that youcome across don't hesistate to ask and I will certainly do some research andhelp 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
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5.  Victoria W Persky, Mary E Turyk, Ling Wang, Sally Freels, RobertChatterton, Jr, Stephen Barnes, John Erdman, Jr, Daniel W Sepkovic, H Leon Bradlow and Susan Potter  (2002). Effect of soy protein onendogenous hormones in postmenopausal women.American Journal of Clinical Nutrition
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