Wednesday, August 8, 2012

Soy consumption myths, truths, and sensationalism!

Soy is a HOT topic and is the source of a heated debate in the nutrition and health community...


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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

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.
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3 comments:

Jeannie said...

Thank you so much for your article. It has definitely put my mind to rest.

Tandi Hartle said...

Jeannie, I'm so glad the article helped you!

Victoria said...

Wow, I am sure that took you a while to write! Great article!