Please Scroll Down to See Forums Below Hey everyone. I need some assistance. I am a strict vegan bodybuilder and eat a large amount of soy for protein. Recently, I have read some research that states that although soy does help lower estrogen levels in men, it also lowers testosterone levels due to the Sex Hormone Binding Globulin (SHBG). Some research says it is great for men, others say it is bad. For those that have done the research, what have you found?
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soy and testosterone
- Thread starter motorwolf
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I was an advocate of Soy Protein and like you, i'm sure did much research and read conflicting things. The good things, Soy does have higher levels of Glutamine, which is good of course, and supposedly can help with such things such as heart disease, cancer and even help with fatloss. On the other hand, I've I've also read things like Soy products contain certain enzymes which can actually prohibit protein absorption (really bad), although I don't know if this is true for Soy Protein Isolate which would be the preferred method of using it.
It sounded good, so I supplemented with Soy Protein Isolate a few seperate occasions and when I did, I used it quite alot. In my personal experience I would have to say that I noticed I became a little leaner, but also noticed that when I eventually switched back to Whey Protein I quickyl got greater gains in strength and size . I don't know if this really had anything to do with Soy Protein and maybe i'm giving too much credit to different proteins, but this is what i think happened and I think i'm unbiased about it.
It sounded good, so I supplemented with Soy Protein Isolate a few seperate occasions and when I did, I used it quite alot. In my personal experience I would have to say that I noticed I became a little leaner, but also noticed that when I eventually switched back to Whey Protein I quickyl got greater gains in strength and size . I don't know if this really had anything to do with Soy Protein and maybe i'm giving too much credit to different proteins, but this is what i think happened and I think i'm unbiased about it.
cyberflash
New member
Gunter Schlierkamp, the German monster - 300+ lbs off season, uses Soy protein with Whey....
I think that Soy has been downplayed by companies selling Whey, because Soy is much cheaper. I take Soy Isolates and mix it with Whey.... I believe in multi protein source.
Soy helped me get leaner. By the way, Glutamine is Anti-catabolic ... which means it preserves muscle mass. And Soy has more than twice the glutamine of whey ...
I haven't heard about soy prohibiting protein absorption ... I think it's crap.
Soy isolates have a very high biological value ... meaning very good absorption ....
Frankly, Soy is great for getting really lean .. and it is the only complete plant protein source ... cholesterol free
I think that Soy has been downplayed by companies selling Whey, because Soy is much cheaper. I take Soy Isolates and mix it with Whey.... I believe in multi protein source.
Soy helped me get leaner. By the way, Glutamine is Anti-catabolic ... which means it preserves muscle mass. And Soy has more than twice the glutamine of whey ...
I haven't heard about soy prohibiting protein absorption ... I think it's crap.
Soy isolates have a very high biological value ... meaning very good absorption ....
Frankly, Soy is great for getting really lean .. and it is the only complete plant protein source ... cholesterol free
chrismac365
New member
RE: Soy and Test levels
I heard the same news on the Today Show.
I think this is not really anything to worry about. It sounded to me like there is a relatively small drop.
If you are a Vegan, chances are your diet lends itself to lower testosterone production in other ways (like lack of cholesterol and lack of natural pro hormones found in meat) - so the soy issue should not be a top worry.
I heard the same news on the Today Show.
I think this is not really anything to worry about. It sounded to me like there is a relatively small drop.
If you are a Vegan, chances are your diet lends itself to lower testosterone production in other ways (like lack of cholesterol and lack of natural pro hormones found in meat) - so the soy issue should not be a top worry.
cyberflash
New member
soy can increase testosterone .... also anti-estrogenic for men ... Japanese men have smaller breast due to this.
it has the reverse effect on women ... increase estrogen.
see article below:
Soy protein BAD, I don't think so.
By Alex Rogers, Proteinfactory.com
Recently, an article was written by a certain Net Magazine, claiming that soy protein was a "Bad" Protein to use if you were a bodybuilder looking to add lean muscle mass. The article concluded with the use of research studies, that soy proteins' phytoestorgens actually lowered testosterone production in animal studies. Hence lower testosterone levels, higher estrogen levels, no muscle gains.
But of course there are always two sides to the story, and I think I have a better case, jury listen up!!!
I would have to disagree, and nutritional experts agree, that soy protein is an excellent protein to use if you're a bodybuilder using the protein to gain muscle mass. Here are a bunch of reasons.
Hormonal Studies
1)A study found that soy protein isolate (daidzein) may have a gender specific normalizing effect on sex-hormone prduction. Male lab animals experienced greater testosterone and growth-hormone excretion as well as muscle growth" This contradicts the study that found that genestein decreased testosterone serum.
2)Another study found that soy may be actually antiestrogenic. . They may also act as antiestrogens by competing for the binding sites of estrogen receptors or the active site of the estrogen biosynthesizing and metabolizing enzymes, such as aromatase and estrogen-specific 17 beta-hydroxysteroid oxidoreductase (type 1).
3)Probably the best research study contracting the one used by the author of "The bad protein" is this.
The phytoestrogens are only found in raw soy products. Not soy protein isolates, which are used as protein supplements for bodybuilders.
"There are very little data on effects of phytoestrogens in males. Estrogenic effects in wildlife have been described but the evidence for the role of phytoestrogens is indirect and seen under conditions of excessive exposure."
And what is most interesting about this study is that it was conducted by one of the same researchers at the same univeristy as the study that found genistein lowered testoserone serum levels. This researcher concluded that even though he found genestein has estrogenic effects, it really cant be concluded because of the above statement in his other reasearch findings. Hence, he found soy to be estrogenic, but it really cant be "hard" evidence because there is not enough proof and it involves ridiculous conditions.
See what I mean by two sides to every story..
Positive Benefits of soy
1) The amino acid profile of soy is excellent. If you don't know by now the Glutamic Acid level is higher than whey. Why? Mainly because it is a plant protein and not dairy.
2) Soy has been proven to lower heart disease risks and cancer. Now there are about a million studies on this statement. I not going to quote any.
3) Soy protein actually improves kidney function.
4) When soy was combined with a carbohydrate in comparison with casein. Lower bodyfat gains were observed.
Character witnessess
it has the reverse effect on women ... increase estrogen.
see article below:
Soy protein BAD, I don't think so.
By Alex Rogers, Proteinfactory.com
Recently, an article was written by a certain Net Magazine, claiming that soy protein was a "Bad" Protein to use if you were a bodybuilder looking to add lean muscle mass. The article concluded with the use of research studies, that soy proteins' phytoestorgens actually lowered testosterone production in animal studies. Hence lower testosterone levels, higher estrogen levels, no muscle gains.
But of course there are always two sides to the story, and I think I have a better case, jury listen up!!!
I would have to disagree, and nutritional experts agree, that soy protein is an excellent protein to use if you're a bodybuilder using the protein to gain muscle mass. Here are a bunch of reasons.
Hormonal Studies
1)A study found that soy protein isolate (daidzein) may have a gender specific normalizing effect on sex-hormone prduction. Male lab animals experienced greater testosterone and growth-hormone excretion as well as muscle growth" This contradicts the study that found that genestein decreased testosterone serum.
2)Another study found that soy may be actually antiestrogenic. . They may also act as antiestrogens by competing for the binding sites of estrogen receptors or the active site of the estrogen biosynthesizing and metabolizing enzymes, such as aromatase and estrogen-specific 17 beta-hydroxysteroid oxidoreductase (type 1).
3)Probably the best research study contracting the one used by the author of "The bad protein" is this.
The phytoestrogens are only found in raw soy products. Not soy protein isolates, which are used as protein supplements for bodybuilders.
"There are very little data on effects of phytoestrogens in males. Estrogenic effects in wildlife have been described but the evidence for the role of phytoestrogens is indirect and seen under conditions of excessive exposure."
And what is most interesting about this study is that it was conducted by one of the same researchers at the same univeristy as the study that found genistein lowered testoserone serum levels. This researcher concluded that even though he found genestein has estrogenic effects, it really cant be concluded because of the above statement in his other reasearch findings. Hence, he found soy to be estrogenic, but it really cant be "hard" evidence because there is not enough proof and it involves ridiculous conditions.
See what I mean by two sides to every story..
Positive Benefits of soy
1) The amino acid profile of soy is excellent. If you don't know by now the Glutamic Acid level is higher than whey. Why? Mainly because it is a plant protein and not dairy.
2) Soy has been proven to lower heart disease risks and cancer. Now there are about a million studies on this statement. I not going to quote any.
3) Soy protein actually improves kidney function.
4) When soy was combined with a carbohydrate in comparison with casein. Lower bodyfat gains were observed.
Character witnessess
soy and test
Cyberflash, thanks for the article and great site reference! As I am really trying to understand this soy affect thing (I am seeing an endocrinologist tomorrow), I have an added question regarding what you stated about men vs. women. Any ideas how the soy would affect a post-menopausal woman or a woman that has had a complete hystorectomy and is not receiving estrogen replacement?
Cyberflash, thanks for the article and great site reference! As I am really trying to understand this soy affect thing (I am seeing an endocrinologist tomorrow), I have an added question regarding what you stated about men vs. women. Any ideas how the soy would affect a post-menopausal woman or a woman that has had a complete hystorectomy and is not receiving estrogen replacement?
cyberflash
New member
I have no idea ... but this is what I can say ... soy is excellent for women based on the studies I have read ...it will lessen cancer and improve women's biological condition ... it should improve post menopausal side effects due to its isoflavones.... but again .. .I'm not a nutritional expert. ... better ask one
If you have thyroid trouble, soy is counter-productive. Many women of a certain age jumped on the soy bandwagon, only to find out that they were slightly hypothryoid, and that eating large amounts of soy actually tipped them into full-scale hypothyroidism.
Not to throw a monkey wrench into the works, but the Sunday NY Times magazine just had a piece on the industry that organic farming has become. One of the largest producers of organic milk, Horizon, actually trucks milk from all over the country and ultra-pasturizes it, thus making it of lower nutritional value than the stuff from local producers in your dairy case. Alas, organic just doesn't mean what it used to.
Not to throw a monkey wrench into the works, but the Sunday NY Times magazine just had a piece on the industry that organic farming has become. One of the largest producers of organic milk, Horizon, actually trucks milk from all over the country and ultra-pasturizes it, thus making it of lower nutritional value than the stuff from local producers in your dairy case. Alas, organic just doesn't mean what it used to.
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