Wednesday, 29 March 2017

Closure to homoSOYxuality

I have been a vegetarian for 20 years now, give and take. I've had my share of soy in the meals I cook, and also in the ones I have in restaurants. So far I can assure you that I still feel the same man, i.e., deeply in love with my wife, still feel attracted to the opposite sex (especially to anyone looking like Jennifer Lawrence, Natalie Portman, Monica Belluci or Charlize Theron), no shrinkage of penis has occurred so far (you'll have to trust me on that for I'll never post any proof on Instagram :P, I don't even have an Instagram account), and I am not infertile (two beautiful babies so far, but I'm stopping there and it's not about the soy beans, it's really that now I need to enjoy the kids and travel with them, show them the world, the different cultures and diversities so they don't blame soy beans for male homosexuality in the future).

I understand the political stance played by a scapegoat decoy, but we must be truthful to the available scientific data collected thus far. The best practice is actually to kind of lightly x-ray the previously referred literature (see post here) and see exactly what was measured, what agents were scrutinised and reference levels suggested to produce significant alterations (reference to these articles can be found in the previous post). Let's start then:

"Altered sexualy dimorphic nucleus of the preoptic area (SDN-POA) volume in adult Long-Evans rats by dietary soy phytoestrogens"

A study using Long-Evans female and male rats where a Phytoestrogens-rich diet and a Phytoestrogens-free diet are put to test. There is a significant reduction in body weight and prostate weight observed, however, testosterone levels are not affected by the different diet treatments; and finally the Phytoestrogens-rich lifelong diet delays puberty onset without impacting on the cycle. The study does not check impact on humans and to be fair never intended to, but other questions we can distill are, for example, how many of us humans would indeed make a life based on phytoestrogens-rich diets? Most likely, no one. And how much phytoestrogens is too much? Where is the threshold? What other foods that make part of our diet also contain high levels of phytoestrogens, and what is a 'high level of phytoestrogens'???!

Again, this is not a judgmental analysis of the study, actually it's quite far from that, but instead a judgmental analysis of anyone using it as proof of soy impacting on human sexual maturation, per se.

"A soy supplement and tamoxifen inhibit sexual behaviour in female rats"

A study focusing on the patterns of sexual behaviour in rodents (rats) based on 'chemotrophism' triggered by progesterone and oestrogen. Diets containing different soy contents were studied as impacting agents on sexual mating behaviour a few hours after ingestion and analysed against a progesterone injection. Overall, the results indicated soy supplement as an oestrogen antagonist - bad news to certain people,  crude news in the overall picture -, but again, how much soy is too much, where's the threshold? I am not considering the study a limited one as to be fair it did study what was proposed in itself, but who can consider phenotypical/biochemical/endocrine changes to male biology simply based on these values? No one.

And to be fair I could go on and one with every single study discussed in the previous soy post, but it wouldn't take us anywhere. So I chose to discuss the hot topic, the one that really has been driving criticism against soy presence in diets go crazy, i.e., soy-based infant formulas.

"Safety of soy-based infant formulas containing isoflavones: The clinical evidence"

For starters, soy-based infant formulas provide a healthy alternative to those children who are lactose-intolerant. Moreover, they agree with the most strict regulatory and safety standards. A comparison study conducted at the University of Iowa, comparing between soy-based infant formula (SBIF) and human milk/cow's milk, and analysing mean weight in infants, resulted in no differences in the first 4 months of development. And a follow-up study of the adults who were fed either SBIFs or cow's milk showed that no differences were produced in their adult weight, for both males and females.

In terms of reproductive development the presence of isoflavones that some scientists attribute to impacting agents affecting sexual maturation stages of those fed with SBIFs, was also evaluated. But this article refers also other research articles written by intelligent people and not by lazy prophets of doom, that backup the complexity of extrapolating potential adverse effects (seen occurring in animal models) into the human biology.

I must quote the article on a few remarkable/excellent observations:

"...rodent studies investigating in utero exposure to isoflavones need to be interpreted in the light of the relatively lower estradiol levels in pregnant rodents compared with pregnant women. The fetal rat is exposed to picomole levels of estradiol whereas the human fetus is exposed to micromole levels of estradiol" [1].

"Fielden et al (2003) [2] studied the effect of gestational and lactational exposure to genistein on testicular weight and sperm quality in adult mice at levels comparable with or greater than human exposure. Results showed no significant treatment-related effects on male offspring body weight, anogenital distance, seminal vesicle weight, or testis weight. However, not all studies concur with these findings [3]". 

"In contrast, clinical studies showed that infants fed SBIF have normal reproductive development and later health. In an abstract, Businco et al (1999) [4] studied 34 children who had been fed SBIFs who were then evaluated at a median age 29 mo. A detailed physical exam included signs of sexual maturation and bone density, metabolic markers of bone, and one marker of estrogen. The investigators’ conclusion was that phytoestrogens in SBIFs did not induce hormonal effects".

And we could go on and on for weeks and get exactly the same feedback we have been comprising thus far. There isn't enough evidence that can suggest that phytoestrogens, to the levels that are fed to people, especially infants, can impact on sexual maturation. As to people turning gay because they are fed SBIF, what can I say???? Homosexuality has been among us since ever and now we need to blame soy for personal options??? What are people going to come up with next? That our politicians don't really want to corrupt, it's the air we breath that is making them selfish pricks?

Well, the judge is still out there for an eventual need to relate phytoestrogens to different sexual orientations. In terms of sexual maturation and aberrant sexual organs' development, we could very much blame parents for smoking, the tones of rubbish put into consumed meat, the completely makeshift foods that are sold in our supermarkets, the quality of our lives filled up with stress and anxiety, the incredible irrational intake of sugar and hydrogenated fats that are generating super obese newborns, the levels of lead that back in the 60s was present in the paint used in cradles and other furniture for children, or even the nail polish solvent ethyl acetate in toothpaste,  etc etc etc. 

I might bring up some hysterical/historical facts on that matter if you guys comment on this post and make me believe it's worth. See you soon and keep using soy, moderately as anything else... you wouldn't drink a whole cow would you? 


[1] Clark, J. H. (1998) Female reproductive and toxicology of estrogen. Korach, K. S. eds. Reproductive and Developmental Toxicology 1998:259-276 Marcel Dekker New York.

[2] Fielden, M. R., Samy, S. M., Chou, K. C. & Zacharewski, T. R. (2003) Effect of human dietary exposure levels of genistein during gestation and lactation on long-term reproductive development and sperm quality in mice. Food Chem. Toxicol. 41:447-454.

[3] Wisniewski, A. B., Klein, S. L., Lakshmanan, Y. & Gearhart, J. P. (2003) Exposure to genistein during gestation and lactation demasculinizes the reproductive system in rats. J. Urol. 169:1582-1586.

[4] Businco, L., Bruno, G., Giampietro, P. G. & Furcolo, G. (1999) No oetrogens hormonal effects in long-term soy formula fed children. J. Allergy Clin. Immunol.103:S169.

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