Talk:Phytoestrogens

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i added a comment on cancer and phytoestrogens and rewrote the part on FSA report. is there a final report? i have only found draft reports on www.food.gov.uk Bedrupsbaneman 5 July 2005 11:45 (UTC)

Added a new section including links to the two major classes of phytoestrogens.


Contents

[edit] Phytoestrogens in Men and Women

I can find a BBC report of the opinion of a Belfast physician, but no published article to go along with it. Dr. Anderson has published her opinion PMID 16234205, but where are her data? Shouldn't this be deleted?Pustelnik 20:17, 6 October 2007 (UTC)

[edit] Merged article

Since "phytoestrogen" and "phytoestrogens" is the same thing and the phytoestrogen article contained only one paragraph I have pasted it into this one. The other article is now redundant and can be deleted.--Tchoutoye

This arcticle still needs a lot of work, especially on the negative health effects of phytoestrogens in food (male infertility, disruption of menstrual cycle, thyroid damage) and on the scale in which they occur (unfermented soya is used in 60% of processed food). A mention could be made of the report of the British Royal Society called "Endocrine Disrupting Chemicals" and the CoT inquiry could be worked out in more detail. One of the committee members, Professor Richard Sharpe head of the Medical Research Council's human reproductive sciences unit at Edinburgh University, has done extensive research on phytoestrogens in food.

Interesting article: the health risks of soya --Tchoutoye 10:54, 26 July 2006 (UTC)

I would be quick to point out that "negative health effects" has a very different meaning for various people. The proper term should be "biological responses", which in this case is likely similar to estrogens. The point of removing the negative spin on the wording, is that there are people who are seeking hormonal alteration, or where such biological responses would not impact them. While thyroid damage could rarely be considered a good thing, disruption of the menstrual cycle is insignificant to those women who have gone through menopause and would gain a benefit from the better stabilization of hormones over any "menstrual distruption" (considering that their menstration is already disrupted.) Also, as for "male infertility", the proper term would be "feminization", which includes impacts upon fertility of men. But there are those people who are seeking this feminization such as transsexuals, and other transgenders, who would see this alteration of hormone levels as a positive rather than a negative. As with anything, negative and positive is in how it is applied, I mean, one "negative health effect" of Botox is nerve inhibition, which can result in death, but properly applied, it can yield effects that simulate youthfulness in older people. At least call it "potential negative effects". And in the future, it would be a good idea to not assume that every male in the world wants to remain so. --Puellanivis 22:11, 26 July 2006 (UTC)
  • This is absolute nonsense. These are not nutritional supplements which a person is free to take or reject. These are part and parcel of all processed foods and fed to the entire population. The large scale results of phytoestrogens are clearly and overwhelmingly negative. 24.200.248.28 23:29, 4 November 2006 (UTC)


  • Speaking of absolute nonsense. It's nonsense to make a statement that alludes to "food processing" having anything to do with the fact that foods contain phytoestrogens. Plants contain them naturally and always have. Not just soy. Yes, even organically grown foods contain them naturally. And they aren't "fed to the entire nation" as some sort of trickery or conspiracy as the writer above would have us believe. Every living thing produces hormones as part of its natural chemistry and we eat those living things. Get over it. 75.70.37.61 17:00, 24 June 2007 (UTC)

Is phytoestrogens same as phyto-oestrogen? e.g. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9329514&dopt=Abstract

[edit] Even for women

it's not so good , and who cares if some transgenders want to take them because they want to be females.

it doesn't make them a healthy substance.


imagine for example if some flower would have phytoandrogens in it. it would soon find it's way in the same place as cannabis and coca in most countries......... makes you feel like theres a conspiracy to make everyone weak timid and docile , and it's working.

seriously at least wikipedia should warn what phytoestrogens or any substance that binds to the estrogen receptor does. for real.

instead of " lower cholesterol and promote bone health " and lower cholesterol could be bad sometimes...

on another note , why am I wasting my time , wikimedia has this medieval mentality , some hippy registered useer will come and call bullshit with some "study" about cholesterol from soy.com —The preceding unsigned comment was added by 88.155.113.162 (talk) 14:54, 11 April 2007 (UTC).

  • I guess there is a reason you want to stay anonymous. Actually, daidzein, a phytoestrogen found in soy and elsewhere, has been described as a phytoandrogen PMID 17252558. There is at least one other phytoandrogen PMID 17261169, and these substances have been implicated in sex-reversal in fish.PMID 12492408 What's your point?Pustelnik 14:02, 13 October 2007 (UTC)

[edit] Effect on humans

How much phytoestrogen in a male human being is required to actually begin feminizing him? Doing a web search for such topics brings up many websites claiming eating soy products, for instance, can have such an effect on a man, but these sites cite few reliable sources, if any at all. Can feminization occur even in normal amounts of soy products? I have been a vegetarian (borderline vegan) for the past three years and I've regularly consumed a good amount of soy products, and I have yet to see such effects in myself. In fact, androgenic body hair, which is sensitive to the level of testosterone in the blood, has increased for me. — Sam 01:43, 6 July 2007 (UTC)

  • A lot. They are much less potent, on a weight for weight basis, than estradiol, often by a factor of 1000 or even 10,000. Because of the way endocrine receptors work, they can act as "weak agonist-antagonists". This means that they have a little effect by themselves, but prevent a more potent estrogen from working. They can block the effects of estrogens naturally produced by males, and you might end up with a lower total estrogen effect. It is naive to say they "might" have an effect, without quoting a peer-reviewed referrence. Toads might cause warts, too. You need proof, otherwise it is just your point of view, and not neutral. Pustelnik 19:35, 6 October 2007 (UTC)


    • This is a news article. What have Drs. Anderson and Lewis published in peer-reviewed journals? Have they published any evidence that eating soy causes breast development in males? If so, I can't find it in PubMed. There is a big difference between a news article or a review article and actual research. Only research is considered to be scientific evidence. Pustelnik 22:51, 8 October 2007 (UTC)
      • They certainly have published something...

http://www.informaworld.com/smpp/content~content=a727272918~db=all

http://www.liebertonline.com/doi/abs/10.1089/10966200152053695

There's (obviously) much more material on male rats, but not from them:

http://www.ingentaconnect.com/content/oup/toxsci/2006/00000091/00000001/art00093

(Effective doses per kg in humans are 10-25x lower than those in rodents btw)

84.50.242.39 (talk) 00:59, 10 February 2008 (UTC)

        • Please sign your posts. The first article quoted states an opinion, but does not involve any actual original rerearch by the authors. The second article is an in-vitro study, and the abstracts state that low doses had no effect on sperm. Having no effect on sperm function is a long way from causing breast tissue growth in males, don't you think? If your question is: "Do soy estrogens cause breast development in human males, in quantities that are plausibly ingested in the diet?", the answer must be "There is no published evidence that they do". If you disagree, please quote a peer-reviewd research article that states the contrary. Please state the source of your claim that effective doses are 10-25 X lower in humans. For what chemicals, and in terms of what effects? Pustelnik (talk) 19:42, 10 February 2008 (UTC)
          • I did sign with the IP, I don't have a username. I did not claim the second article is on mammary gland tissue, it's just an example that these two authors do study, and publish articles on, phytoestrogens. I do not care enough to carry out an in-depth search on all their publications and everything published in the field, and record all my sources. I just wanted to point out that safety cannot be assumed, esp. in pregnant women (and was hoping someone else would have the time to go deeper). If it isn't for the estrogenic effect, the anti-thyroid effect is still an obvious reason to avoid at least genistein and daidzein. 82.131.19.119 (talk) 01:29, 14 February 2008 (UTC)

[edit] Section "Health risks" disputable

Section "Health risks" contains disputable claims:

"Phytoestrogens have the same effect as normal estrogens [...]" This is wrong. So-called "phytoestrogens" have a much lower estrogenic effect than estrogens.

"and in high quantity are known to cause gynecomastia [...], lower androgen levels in men, infertility, early bone maturation [...]" Such claims are highly controversial amongst the endocrinologic community, i.e., they are not "known to".

"and some isoflavones can enlarge the population of estrogen receptors in certain tissues." Like the whole sentence, references are missing.

I have removed all specific unreferenced health risks and simply replaced the section describing infertility etc with unresearched concerns over hormonal imbalances. All of these issues are merely speculation and have no real scientific basis as far as I've managed to find. Halogenated 17:02, 13 September 2007 (UTC)

Please see http://en.wikipedia.org/wiki/Soy#Soy_controversy for comparison.


  • I agree, and have tried to clean up the referrences. I can find no published report of gynecomastia due to phytoestrogens. Speculation is not evidence, and most of the adverse claims are not backed up with any study actually showing any adverse effect, but see the "minor effects on serum reproductive hormones" referrence" for an example as to how such claims could be verified.Pustelnik 18:28, 7 October 2007 (UTC)
    • There certainly is abnormal mammary gland development in male rats:

http://www.ingentaconnect.com/content/oup/toxsci/2006/00000091/00000001/art00093

Doing such tests on humans would be complicated, as you can guess...

84.50.242.39 (talk) 00:51, 10 February 2008 (UTC)

[edit] Cleaned Up

I merged a couple of sections, removed a number of unreferenced and unsubstantiated comments and generally clean a few parts up. It's not great, but at least it is more accurate. Halogenated 17:14, 13 September 2007 (UTC)

[edit] Good Work

This article is really starting to come along! When I first stumbled across it I found myself compelled to try and edit out some of the obvious flawed assertions and claims without causing too much fuss, as my area of expertise is far from here! I'm glad to see the interest taken up by Pustelnik and Jennylee who evidently are much better versed on the topic. Cheers! Halogenated 03:57, 13 October 2007 (UTC)

Sometimes a keen interest and steady contributions as you have done and continue doing is as important as knowledge on the topic. Keep up the good work! JennyLen☤ 06:16, 13 October 2007 (UTC)
Yeah! Thanks to the folks cleaning up the urban legend stuff from this article. Came here looking to see if there was real research to back up claims that Yoruban Nigerians have a high rate of twins, and that it's caused by phytoestrogens in the yams they eat. Didn't find any; don't think there is any. -Anon. —Preceding unsigned comment added by 71.191.16.16 (talk) 03:59, 17 February 2008 (UTC)