Why Does Soy Reduce Estrogen Levels In Studies?

[biohacked]

Soy is widely known in health circles as pro-estrogenic and feminizing and men are recommended to avoid it. If that’s actually the case, can anyone explain why serum estrogen levels actually decrease in soy-supplemented groups in studies in both men and women? And why is there an inverse relationship between hormone dependent cancers such as breast and prostate cancer (I suppose all cancers are hormone dependent) and soy consumption? Here are just some of the studies I’m talking about:

ncbi.nlm.nih.gov/pubmed/8770469 - 36-oz of daily soymilk consumption for a month significantly decreased serum 17 beta-estradiol levels in premenopausal women.

ncbi.nlm.nih.gov/pubmed/9839524 - Estrone and estradiol levels were decreased by 23% and 27% at the end of the study in the soy milk supplemented group in Japanese women. The change in estrone and estradiol levels was minor in the control, non-soy group.

ncbi.nlm.nih.gov/pubmed/11303585 - Serum estrone concentrations decreased in the soy-supplemented group in Japanese men. There was no change in testosterone levels in both the soy group and the control group.

Is it that the estrogen circulation in blood decreases from soy but estrogen level inside the cell increases? Is that why soy is so widely considered as ‘estrogenic’?

 

[jdwaca]

Soy is widely known in health circles as pro-estrogenic and feminizing and men are recommended to avoid it. If that’s actually the case, can anyone explain why serum estrogen levels actually decrease in soy-supplemented groups in studies in both men and women? And why is there an inverse relationship between hormone dependent cancers such as breast and prostate cancer (I suppose all cancers are hormone dependent) and soy consumption? Here are just some of the studies I’m talking about:

ncbi.nlm.nih.gov/pubmed/8770469 - 36-oz of daily soymilk consumption for a month significantly decreased serum 17 beta-estradiol levels in premenopausal women.

ncbi.nlm.nih.gov/pubmed/9839524 - Estrone and estradiol levels were decreased by 23% and 27% at the end of the study in the soy milk supplemented group in Japanese women. The change in estrone and estradiol levels was minor in the control, non-soy group.

ncbi.nlm.nih.gov/pubmed/11303585 - Serum estrone concentrations decreased in the soy-supplemented group in Japanese men. There was no change in testosterone levels in both the soy group and the control group.

Is it that the estrogen circulation in blood decreases from soy but estrogen level inside the cell increases? Is that why soy is so widely considered as ‘estrogenic’?

I didn’t take a look at the actual studies because I saw a couple key words that were dead giveaways. Key word, Japanese.

From what I was taught in school (degrees are in nutrition....not to sound all “high and mighty”, just passing along knowledge) different demographics of people will yield different results. Asian cultures have been consuming soy, and soy based products for centuries. Their bodies are accustomed to it, and react differently than that of other cultures. Another example would be the water in Mexico. If Americans drink it, they get sick, but the Mexican people have adapted to the impurities/contaminants etc. Not the same thing exactly, but you get the idea.

What you need to look at are studies on American populations. You’ll find the results are the exact opposite in many cases. In others, you’ll see no change. While most studies will lead you to believe soy products are harmful, there is some margin of error. Personally, I do not eat anything largely comprised of soy. For several reasons. This happens to be one of them. There is enough evidence for me to conclude that soy is probably not the best food to be consuming. But like I said, take every study with a grain of salt. To each their own.

 

[biohacked]

Thanks for the response, jdwaca, pretty interesting view on this, but I do find it a bit hard to buy that the ethnical difference would be so big that amongst one ethnicity there would be a significant reduction in estrogen while another (Americans for example) would have an increase. I'm not sure that 'centuries' would be enough of a time period to adapt to soy consumption, where it becomes the complete opposite effect in people than the one that (supposedly) should be seen. Any studies on Western populations that you can point me to? Thanks.

 

[jdwaca]

Thanks for the response, jdwaca, pretty interesting view on this, but I do find it a bit hard to buy that the ethnical difference would be so big that amongst one ethnicity there would be a significant reduction in estrogen while another (Americans for example) would have an increase. I'm not sure that 'centuries' would be enough of a time period to adapt to soy consumption, where it becomes the complete opposite effect in people than the one that (supposedly) should be seen. Any studies on Western populations that you can point me to? Thanks.

I say centuries, but it’s actually many centuries, more like thousands of years. The effects on Americans are attributed to the phytoestrogens in soy, and the fact that relatively speaking, soy has only been recently introduced into the American diet. I would assume the same to be true for other similar cultures, not just Americans. Western Europeans for example. I understand your questioning though. I don’t know the names of studies of the top of my head. I would have to look it up. I’ll see what I can find tomorrow.

 

[u_e_s_i]

Soy contains a lot of phytoestrogens which are estrogen-like compounds made by plants. Interestingly these have estrogenic effects on the human body

 

[jdwaca]

Thanks for the response, jdwaca, pretty interesting view on this, but I do find it a bit hard to buy that the ethnical difference would be so big that amongst one ethnicity there would be a significant reduction in estrogen while another (Americans for example) would have an increase. I'm not sure that 'centuries' would be enough of a time period to adapt to soy consumption, where it becomes the complete opposite effect in people than the one that (supposedly) should be seen. Any studies on Western populations that you can point me to? Thanks.

Here’s an interesting article from the National Center for Biotechnology Information. (Link posted below). Under Health Effects of Soy, about midway through, it discusses the differences between Asian and American diets and adaptations.

A factor I forgot to mention, that his study reminded me of, is that coy consumption in toddlers and infants, can have drastic health ramifications. Such as early onset of puberty, endocrine system disruption, and alterations in development of breast tissue (developmental health in general). There is also strong evidence proving disruption of several neurotransmitter systems, which have cascading damaging effects. Concern levels vary across the board, depending on the expert, but generally all acknowledge that there is some concern. Most of the information on this study stems from the consumption of soy based formula as an infant. Soy formula is terrible for a child.

.ncbi.nlm.nih.gov/pmc/articles/PMC1480510/

 

[jdwaca]

Here’s an interesting article from the National Center for Biotechnology Information. (Link posted below). Under Health Effects of Soy, about midway through, it discusses the differences between Asian and American diets and adaptations.

A factor I forgot to mention, that his study reminded me of, is that coy consumption in toddlers and infants, can have drastic health ramifications. Such as early onset of puberty, endocrine system disruption, and alterations in development of breast tissue (developmental health in general). There is also strong evidence proving disruption of several neurotransmitter systems, which have cascading damaging effects. Concern levels vary across the board, depending on the expert, but generally all acknowledge that there is some concern. Most of the information on this study stems from the consumption of soy based formula as an infant. Soy formula is terrible for a child.

.ncbi.nlm.nih.gov/pmc/articles/PMC1480510/

Wouldn’t let me post the actual link because my post count isn’t high enough, which I think is irrelevant and f’ing stupid....so put www in front of the half ass link on my previous post.

 

[biohacked]

Thanks for the article, as I mentioned in the first post, I realise that the consensus amongst most is that soy should be avoided and is estrogenic, I just haven't been able to find concrete studies that would confirm that (found the opposite, in fact). Also, while the phytoestrogens in soy are estrogenic, their activity is supposedly a lot weaker than estrogen. Since they theoretically bind to estrogen receptors, replacing estrogen, the net estrogenic activity should be lower than had you not consumed phytoestrgens and let estrogen become active by binding to its receptors - at least that's my thinking on that.
The problem with the article you posted is that, again, it doesn't reference any studies that would actually prove that soy is feminising or estrogenic. It's certainly interesting but in this case, it was all theory.

 

[jdwaca]

Thanks for the article, as I mentioned in the first post, I realise that the consensus amongst most is that soy should be avoided and is estrogenic, I just haven't been able to find concrete studies that would confirm that (found the opposite, in fact). Also, while the phytoestrogens in soy are estrogenic, their activity is supposedly a lot weaker than estrogen. Since they theoretically bind to estrogen receptors, replacing estrogen, the net estrogenic activity should be lower than had you not consumed phytoestrgens and let estrogen become active by binding to its receptors - at least that's my thinking on that.
The problem with the article you posted is that, again, it doesn't reference any studies that would actually prove that soy is feminising or estrogenic. It's certainly interesting but in this case, it was all theory.

A “theory” from the US National Library of Medicine. Lol. K.

 

[biohacked]

A “theory” from the US National Library of Medicine. Lol. K.

Alright, where's the data and studies showing anything they claimed then (they referenced none)? Why does it matter that it's 'US National Library of Medicine'? If you don't reference any research then there is no proof that what you're saying is true. How is then the article you posted not theory? If there's research out there that I don't know about, sure, if one shows it to me, I'll analyze it and reconsider.

 

[jdwaca]

A few quotes taken from ncbi.nlm.nih.gov/pmc/articles/PMC5241282/
There are also 190 sources listed from doctors, and medical journals, and the studies are cited at the end of article. One of many articles on the topic. There are just SOME examples. Bottom line, as with most controversial studies/topics, is the information can be conflicting. But if someone told you, "hey...if you eat this it could help you....or it could hurt you", would you eat it? Or just stay away due to the lack of knowledge and conflicting information? Do what you want, I'm just saying medicine has a valid, definitive argument against soy, especially in young adults. And pay attention to paragraph 6 noting the differences in Asian biological factors to those of American and some European cultures. As I mentioned before in the previous "theory".


SIF is associated with very early as well as late menarche (178, 179), and with heavy menstrual bleeding and larger uterine fibroids

In addition to reproductive organs, allergy and cognitive testing at multiple stages of development could discern differences in immune system and cognitive development. The retrospective study by Strom and colleagues (136) found associations with menstrual, asthma, and allergy phenotypes in relation to infant diet.

We conducted a retrospective analysis of the Simons Foundation Autism Research Initiative (SFARI) medical record database (139). There was a 2.6-fold higher rate of febrile seizures, a 2.1-fold higher rate of epilepsy comorbidity, and a 4-fold higher rate of simple partial seizures in autistic children fed SIF. In addition to seizures, there was an increased incidence of allergies, attention-deficit hyperactivity disorder, asthma, and bipolar disorder in the SIF cohort

In addition to neurological and immune health, soy isoflavones affect development of the intestines as well as the makeup of the intestinal microbiota (146). There have been two studies investigating the influence of SIF on the gut microflora in infants and/or children. The first study found increased equol excretion in the soy group (19%) compared to controls (5%) with elevated Bifidobacteria, Bacteroides, and Clostridia bacteria in fecal samples from the soy group (147). The second study found elevated Bifidobacteria species (B. adolescentis and B. infantis), which were not detected before commencing the SIF (148).

Bifidobaterium, Bacteriodes, and Clostridium are among the human intestinal bacteria that can produce S-equol (149, 150). S-equol is the biologically active metabolite of daidzein. Intestinal bacteria transform daidzein to equol in humans that are equol producers. In Japan, Korea, and China, up to 80% of people are equol producers, but as few as 25% of people in North America and Europe can biotransform daidzein into equol (150). Equol modulates expression of the BRCA1 and BRCA2 breast cancer genes through an epigenetic mechanism resulting in decreased methylation, which results in an increased level of oncosuppressors in breast cancer cell lines (151. (In other words, can decrease cancer in Asian populations)

Overall, lack of knowledge related to the effects of SIF and agrochemicals on health could be equated with the state of affairs of cigarette smoking in the 1950s when smoking was generally regarded as safe. Over 50 years after the Surgeon General first warned of the health hazards of smoking, tobacco use is still a large burden in the United States where 18% of adults smoke.7 Decades later, there are no RCT that prove smoking causes lung cancer; however, enough evidence has accumulated where an RCT would be unethical. One could envision a similar scenario unfolding as evidence accumulates regarding adverse health effects associated with agrochemicals and GM food. A summary of the known effects of infant feeding on childhood development is provided in Figure Figure22.(Figure 2 shows an increase in seizures with soy formula)

 

[biohacked]

Thanks for that. Doesn't that make you think though, that the problems with infants on soy is because they didn't simply recieve human milk, which has all the necessary factors for developement rather than because they consumed soy? It could also very well mean that it's not soy itself that's bad but not receiving mother's milk is the cause of problems. Soy was just the substitute. Infants on cow's milk for instance do much worse than on soy. Should that mean we shouldn't consume dairy? Is there any research like this on adults? I don't think the stance is definitive at all. As you said yourself the informatioln is conflicting.

 

[jdwaca]

Thanks for that. Doesn't that make you think though, that the problems with infants on soy is because they didn't simply recieve human milk, which has all the necessary factors for developement rather than because they consumed soy? It could also very well mean that it's not soy itself that's bad but not receiving mother's milk is the cause of problems. Soy was just the substitute. Infants on cow's milk for instance do much worse than on soy. Should that mean we shouldn't consume dairy? Is there any research like this on adults?

Some of those studies that had infants on soy based formula, had comparative groups of infants on dairy-based formula as well as breast milk as controls. This soy based group is the only group that received those results.

And correct, infants should not consume dairy.

There is information on adults but the studies are all conflicting. It seems that the results also very by age group, and culture. Some studies will say it is completely fine and maybe even healthy, and other studies will say how harmful it can be to your endocrine system, reproductive system etc. It just depends on the parameters of the study. You have to take into account the age group, the demographic, and the controls used. A lot of the studies saying soy is safe and beneficial, were done on cultures other than the American culture.

Conclusions can be drawn any way that you want, and an argument can literally be made for either case. But why take the chance consuming something that really isn’t that big of a staple of most peoples diets.


*dictation text. Excuse typos

 

[biohacked]

Yeah but the problem is that you have to eat something at the end of the day. If you consumed only foods that didn't have conflicting evidence you'd be pretty much left with fruits, vegetables and grains (even if that). That approach would only make sense if very few foods had conflicting research behind them. Don't tell me animal products like fish, eggs, dairy, meat as well as common things like bread don't have a ton of conflicting research behind them. Do you avoid all of those as well because of that? I'd rather take the time to find or not find the flaws in either type of research (whether it shows benefit or harm for any food) rather than go by the fact that there is mixed evidence, so we should stay away.
Anyways, thanks for the discussion.

 

[jdwaca]

Yeah but the problem is that you have to eat something at the end of the day. If you consumed only foods that didn't have conflicting evidence you'd be pretty much left with fruits, vegetables and grains (even if that). That approach would only make sense if very few foods had conflicting research behind them. Don't tell me animal products like fish, eggs, dairy, meat as well as common things like bread don't have a ton of conflicting research behind them. Do you avoid all of those as well because of that? I'd rather take the time to find or not find the flaws in either type of research (whether it shows benefit or harm).
Anyways, thanks for the discussion.

There is conflicting information with everything you just listed, but not to the effects of Soy. I would not eat beef if they said it could mimic estrogen in my body and potentially lead to developmental and reproductive issues in young adults. All of the information on the food you listed is very very minor when compared to the potential harmful effects of soy products. Take the egg for example. Is the egg good? Or bad? The debate has been going back-and-forth for years. Last I heard, The egg is considered good once again because the cholesterol in the egg doesn’t directly iimpact the cholesterol in your bloodstream. Even if it did, I don’t think that would sway people from not ever consuming eggs.

I do think of those things when choosing foods though. I eat organic when I can, and avoid things like farm raised fish (salmon, tilapia, etc).....and soy

 

[biohacked]

Yeah but has it actually been proven that soy leads to developemental disorders? You posted that paper on soy infant formula but as I mentioned in the first post, why does it decrease estrogen levels if it is feminizing and I already stated that developemental problems could be because of a lack of human milk in that case. You said that infants shouldn't drink cow's milk. Ok, if we agree that infants shouldn't also drink soy milk, why do you extend that to adults as well in the case of soy but not in the case of dairy? You really seem to over-demonise it in your last post but as I said I actually haven't seen any solid eveidence on that in adults. Sure I eat organic as well and don't eat industrial meats and fish.

Edit: Also people who think eggs don't raise cholesterol don't know how to read studies properly. The studies that show that eggs 'don't increase' cholesterol didn't measure cholesterol levels at baseline. All the studies that did measure the baseline cholesterol of subjects (such as metabolic ward studies) clearly show the raise in cholesterol from egg consumption.

 

[jdwaca]

Yeah but has it actually been proven that soy leads to developemental disorders? You posted that paper on soy infant formula but as I mentioned in the first post, why does it decrease estrogen levels if it is feminizing and I already stated that developemental problems could be because of a lack of human milk in that case. You said that infants shouldn't drink cow's milk. Ok, if we agree that infants shouldn't also drink soy milk, why do you extend that to adults as well in the case of soy but not in the case of dairy? You really seem to over-demonise it in your last post but as I said I actually haven't seen any solid eveidence on that in adults. Sure I eat organic as well and don't eat industrial meats and fish.

Edit: Also people who think eggs don't raise cholesterol don't know how to read studies properly.

And what population of people did you see that effect on?

The digestive ssystems of infants are not capable of properly digesting dairy products. As you develop into adults that no longer seems to be the case for most. But still some people are intolerant to dairy. And when I say infant, I’m referring to literally infant babies. After a couple years of growth and development the intolerance to dairy products tends to subside.

And yes it has been proven. Did you not read that study? There was even Suggestion that lower IQs can result from consuming soy. Although ethics prevents this from ever being proven. Not just cognitive development, but reproductive, and endocrine as well.

I’m done going round and round. I’m basing my opinion on what I was taught through 2 nutrition degrees, and from what I’ve read on the topic.

If you want to eat soy, go for it. I feel like we’re starting to split hairs. You say you eat organic? Why? Because of hormones, antibiotics, types of feed given to animals etc? So? The USDA says it’s safe, yet you avoid it because MAYBE it’s bad, which I think is a good choice. But when it comes to soy, your up to bat for soy. Very confusing.

Anyway. To each their own. To eat or not to eat.

(Those questions above were rhetorical by the way. You don’t have to respond. I’m turning off the notifications to this post. Tired of kicking a dead horse)