The Truth About Soy Protein? (open discussion)

[JoeySon]

Hey guys,
Now I'm sure there are several other threads about this but I wanted to open a new one for my purposes. I have a short research paper to write in my nutrition therapy class and our choice of topics was very broad. We were allowed to pick "any food, supplement, or diet that has been recently debated." We then need to research some claims made about the topic of choice and decide which side we agree with or if there is inconclusive evidence available. I chose to do mine on soy protein and whether or not some of the claims that seem a little crazy (IMO) have any validity.

Some claims about Soy protein:

-increased estrogen

-consumption of soy increases risk of some types of cancer

-soy lowers cholesterol when consumed in amounts of 25g *

-babies should not consume soy products/formula

-Soy has negative effects on fertility

An argument I find interesting in soy's favor is that Asian cultures have consumed soy for thousands of years and have no noticeable health problems associated.

Hopefully I didn't lose you on the lengthy opening post but I'm eager to hear your guys thoughts and I'm opening it up to the AM community. I'm not asking you to do my work but anything factual you can contribute would be greatly appreciated!

Joey

[grandroid828]

Cant speak too much about it, and this is just a suggestion, but 1,3 dimethylamine is a VERY recent and highly debatable supplement. Might be a better topic. Either way good luck!

[BBB]

I'm looking for answers on the use of soy also. I've tried to do some research and only get even more confused. However, I have stayed away because of estrogen concerns.

[djbombsquad]

Hey guys,
Now I'm sure there are several other threads about this but I wanted to open a new one for my purposes. I have a short research paper to write in my nutrition therapy class and our choice of topics was very broad. We were allowed to pick "any food, supplement, or diet that has been recently debated." We then need to research some claims made about the topic of choice and decide which side we agree with or if there is inconclusive evidence available. I chose to do mine on soy protein and whether or not some of the claims that seem a little crazy (IMO) have any validity.

Some claims about Soy protein:

-increased estrogen

-consumption of soy increases risk of some types of cancer

-soy lowers cholesterol when consumed in amounts of 25g *

-babies should not consume soy products/formula

-Soy has negative effects on fertility

An argument I find interesting in soy's favor is that Asian cultures have consumed soy for thousands of years and have no noticeable health problems associated.

Hopefully I didn't lose you on the lengthy opening post but I'm eager to hear your guys thoughts and I'm opening it up to the AM community. I'm not asking you to do my work but anything factual you can contribute would be greatly appreciated!

Joey

Depending on how it's washed etc so is a low carb choice for protein and is easy on the stomach . I have no boobs and I consume soy all the time. Some benefits is that it helps with inslin too.

[JoeySon]

Cant speak too much about it, and this is just a suggestion, but 1,3 dimethylamine is a VERY recent and highly debatable supplement. Might be a better topic. Either way good luck!

I had considered this but chose soy out of my own curiosity

[JoeySon]

I'm looking for answers on the use of soy also. I've tried to do some research and only get even more confused. However, I have stayed away because of estrogen concerns.

From what I've read you need to ingest a very large amount of soy to have those affects

[AaronJP1]

Started ya own huh?

[JoeySon]

Started ya own huh?

Yea didn't see yours until after. With our powers combined...lol

[mumbles12]

would not risk it with soy personally.. too much fortification anyway

[BBB]

Scientists have differed on the potential implications of the increase of isoflavones in the body. In men, some would lead you to believe that an increase in isoflavones would have a feminizing effect on the male because estrogen is a hormone found more abundantly in females. However, this is most likely not the case. Some doctors have pointed out that since isoflavones do bind estrogen receptor cells instead of normal estrogen compounds, that the overall effect could minimize the amount of estrogen present in males instead of increasing it. For females, the isoflavones can limit estrogen production as well for those who are hormonally imbalanced to begin with. Also, increases in estrogen levels that are not the direct result of pregnancy can lead to an increased risk in developing kidney and ovarian cancer over time. This becomes more likely after the age of 35.
Benefits Versus Risks

So, there are some risks to increasing your overall intake of estrogen by consuming soy-based products. Isoflavones do have some effect of estrogen levels, but it is not yet clear to what extent these compounds affect the regulation of that hormone. So, do these risks outweigh the benefits inherent to increasing your intake of soy protein? This more-or-less depends on your situation. Soy products can be major boons for those who are at a higher risk for heart-related problems. Since they offer a low-fat and low-cholesterol alternative to meat-based protein sources, those who are at a higher risk for heart disease would probably be better served to sticking with soy instead of returning to a reliance on meat-based protein. You should also keep in mind that in many countries in Asia, the daily intake of isoflavones is 5-10 times higher than in the West and yet there is a lower incidence rate of heart disease and cancer.

[BBB]

Soy protein isolate increases urinary estrogens and the ratio of 2:16alpha-hydroxyestrone in men at high risk of prostate cancer.

Hamilton-Reeves JM, Rebello SA, Thomas W, Slaton JW, Kurzer MS.
Source

Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108, USA.

Abstract

Specific estrogen metabolites may initiate and promote hormone-related cancers. In epidemiological studies, significantly lower excretion of urinary estradiol (E2) and lower ratio of urinary 2-hydroxy estrogens to 16alpha-hydroxyestrone (2:16 OH-E1) have been reported in prostate cancer cases compared to controls. Although soy supplementation has been shown to increase the ratio 2:16 OH-E1 in women, no studies to our knowledge have investigated the effects of soy supplementation on estrogen metabolism in men. The objective of this randomized controlled trial was to determine the effects of soy protein isolate consumption on estrogen metabolism in men at high risk for developing advanced prostate cancer. Fifty-eight men supplemented their habitual diets with 1 of 3 protein isolates: 1) isoflavone-rich soy protein isolate (SPI+) (107 mg isoflavones/d); 2) alcohol-washed soy protein isolate (SPI-) (<6 mg isoflavones/d); or 3) milk protein isolate (MPI), each providing 40 g protein/d. At 0, 3, and 6 mo of supplementation, the urinary estrogen metabolite profile was measured by GC-MS. Both soy groups had higher E2 excretion than the MPI group at 3 and 6 mo. After 6 mo of supplementation, the SPI+ group had a significantly higher urinary 2:16 OH-E1 ratio than the MPI group. Increased urinary E2 excretion and 2:16 OH-E1 ratio in men consuming soy protein isolate are consistent with studies in postmenopausal women and suggest that soy consumption may be beneficial in men at high risk of progressing to advanced prostate cancer as a result of effects on endogenous estrogen metabolism.

PMID: 17885008 [PubMed - indexed for MEDLINE] Free full text

[BBB]

Does consuming soy affect hormone levels?

Answered by Mark Messina, PhD, MS
SharePrint
Some recent postings suggest that people avoid soy (tofu and soymilk) because of its effects on hormone levels. While confusion around this topic is certainly understandable, I can assure you as someone who has studied this area professionally for the past 20 years, when one considers the clinical (human intervention) data, there is no reason to be concerned about soyfoods. Confusion arises only when one considers the results of animal studies. However, not only do these studies have little relevance to humans—in part because rodents metabolize soy differently than humans¹—there is no reason to rely upon them for insight because of the wealth of clinical data available on soyfoods.
With respect to the effects of soy phytoestrogens (isoflavones) on hormone levels, a recently published meta-analysis that included 32 clinical studies showed that neither isoflavone-rich soy protein nor isoflavones affect reproductive hormone levels in men, including both total and free testosterone and total and free dihydrotestosterone.² Similarly, a meta-analysis that included 47 clinical studies showed neither soy nor isoflavones had meaningful effects on reproductive hormone levels in pre- or postmenopausal women. ³ Also, a recent comprehensive review found soy does not exert feminizing effects in men; this review included 9 studies that showed soy does not affect estrogen levels.⁴ It is noteworthy that many of the studies included in the two meta-analyses and one review cited above involved interventions in which soy and isoflavone exposure far exceed that typical for Asia.
As to the fermented vs. non-fermented soyfood issue, both foods are good choices. Both types contain equivalent amounts of isoflavones, so if isoflavones are a concern, one type of food doesn’t hold an advantage over the other. Arguments that fermented soyfoods are superior to non-fermented ones are often based on claims that fermentation inactivates or destroys protease inhibitors (which inhibit protein digestion) and phytic acid (which inhibits mineral absorption), compounds which are naturally present in soybeans and many plant foods. However, the digestibility of soy protein from non-fermented soyfoods approaches 100%, so there is little room for improvement.^5-9 Furthermore, despite the presence of phytic acid and oxalate, current research indicates that daily soy consumption does not impact mineral absoroption over the long term.¹⁰
Finally, there is a considerable amount of evidence indicating that soyfoods provide health benefits independent of their nutrient content. For example, there are both animal and epidemiologic data indicating soy consumption during childhood and/or adolescence reduces breast cancer risk. In addition, there is evidence indicating soy may be useful for both the prevention and treatment of prostate cancer, and for several reasons, soyfoods are very heart-healthy. One can have a healthy diet without ever eating soyfoods but it would be unfortunate for people to avoid these nutritious foods because of a misunderstanding about their health effects.

[hossjob]

This is cool. I try to avoid soy at all costs and would like to learn more about it. I've jsut always been under the assumption (from articles i've ready, I've never pursued actual research - which I probably should - ignorance on my part) because soy is so abundantly found in packaged foods and additives and condiments. I'm goint to follow this thread. Thanks for starting this.

[pushinweightw]

One thing to consider in the populations that ingest soy is the form in which they do so. Is it fermented? Is it organic? Is it in a processed form like soy isolate? Also consider that much of the soy in the US is genetically modified soy. Does this make a difference? Depends on who you talk to. Also when looking at the health of populations that have consumed soy traditionally one must take into account the whole diet of the populace as well as lifestyles such as daily exercise/activity.

[JoeySon]

Does consuming soy affect hormone levels?

Answered by Mark Messina, PhD, MS
SharePrint
Some recent postings suggest that people avoid soy (tofu and soymilk) because of its effects on hormone levels. While confusion around this topic is certainly understandable, I can assure you as someone who has studied this area professionally for the past 20 years, when one considers the clinical (human intervention) data, there is no reason to be concerned about soyfoods. Confusion arises only when one considers the results of animal studies. However, not only do these studies have little relevance to humans—in part because rodents metabolize soy differently than humans¹—there is no reason to rely upon them for insight because of the wealth of clinical data available on soyfoods.
With respect to the effects of soy phytoestrogens (isoflavones) on hormone levels, a recently published meta-analysis that included 32 clinical studies showed that neither isoflavone-rich soy protein nor isoflavones affect reproductive hormone levels in men, including both total and free testosterone and total and free dihydrotestosterone.² Similarly, a meta-analysis that included 47 clinical studies showed neither soy nor isoflavones had meaningful effects on reproductive hormone levels in pre- or postmenopausal women. ³ Also, a recent comprehensive review found soy does not exert feminizing effects in men; this review included 9 studies that showed soy does not affect estrogen levels.⁴ It is noteworthy that many of the studies included in the two meta-analyses and one review cited above involved interventions in which soy and isoflavone exposure far exceed that typical for Asia.
As to the fermented vs. non-fermented soyfood issue, both foods are good choices. Both types contain equivalent amounts of isoflavones, so if isoflavones are a concern, one type of food doesn’t hold an advantage over the other. Arguments that fermented soyfoods are superior to non-fermented ones are often based on claims that fermentation inactivates or destroys protease inhibitors (which inhibit protein digestion) and phytic acid (which inhibits mineral absorption), compounds which are naturally present in soybeans and many plant foods. However, the digestibility of soy protein from non-fermented soyfoods approaches 100%, so there is little room for improvement.^5-9 Furthermore, despite the presence of phytic acid and oxalate, current research indicates that daily soy consumption does not impact mineral absoroption over the long term.¹⁰
Finally, there is a considerable amount of evidence indicating that soyfoods provide health benefits independent of their nutrient content. For example, there are both animal and epidemiologic data indicating soy consumption during childhood and/or adolescence reduces breast cancer risk. In addition, there is evidence indicating soy may be useful for both the prevention and treatment of prostate cancer, and for several reasons, soyfoods are very heart-healthy. One can have a healthy diet without ever eating soyfoods but it would be unfortunate for people to avoid these nutritious foods because of a misunderstanding about their health effects.

That really sticks out to me in my beginning of the research. It seems all men need to see is the word estrogen and they run away when in fact I have yet to find one concrete study that states it simply raises estro in HUMANS

Also, I know "up your mass" is a very popular weight gainer and its main source of protein is soy iso..so then the countless people who have used it now have increased estro side effects? I find that hard to believe

[JoeySon]

One thing to consider in the populations that ingest soy is the form in which they do so. Is it fermented? Is it organic? Is it in a processed form like soy isolate? Also consider that much of the soy in the US is genetically modified soy. Does this make a difference? Depends on who you talk to. Also when looking at the health of populations that have consumed soy traditionally one must take into account the whole diet of the populace as well as lifestyles such as daily exercise/activity.

I think this is a great point..I was looking at different types of soy protein powder and soy concentrate is actually processed and rinsed with alcahol which is scary in itself

[JoeySon]

So I walked into my locally owned supplement shop and just asked the guy if they carried soy protein and he said "absolutely not" when I asked him why the only answer he could muster was "it's ****ty stuff" I was hoping to have a somewhat intelligent conversation with him, oh well lol fail

[JoeySon]

would not risk it with soy personally.. too much fortification anyway

Care to elaborate? Not challenging you, just curious

[JudoJosh]

Soy isoflavones are anti-androgenic. They impair Leydig cell function, androgen receptor sensitivity and erectile function (albeit in rodents) but there is sufficient research on human males showing that even a modest consumption (50g a day) will reduce testos levels and has also been shown to reduce androgen receptor expression.

Even besides that soy is very difficult to digest, a common allergen and comes with the unnecessary estrogen baggage. So my question is with the availability of milk and egg proteins, why bother with soy?

[EBF Inc]

Soy isoflavones are anti-androgenic. They impair Leydig cell function, androgen receptor sensitivity and erectile function (albeit in rodents) but there is sufficient research on human males showing that even a modest consumption (50g a day) will reduce testos levels and has also been shown to reduce androgen receptor expression.

Even besides that soy is very difficult to digest, a common allergen and comes with the unnecessary estrogen baggage. So my question is with the availability of milk and egg proteins, why bother with soy?

Certain flavones can be beneficial tho

Eqoul topically for hair regrowth

Kampeferol for fat burning