[CKD] soybean oil

[Iron Bull]

What's the deal with soybean oil. I get nervous just looking at the word soy. Does this stuff raise estrogen levels and kill testosterone or what? :confused:

[west_on_46]

My MedLine search turned up a bunch of garbage so far.

There seems to be a lot of clamoring about soy on really shaky logic, that being: It's known that female hormones have cardioprotective effect; since soy contains phytoestrogens, it must have a cardioprotective effect as well, right? Well... maybe, maybe not. I'm not contesting that. I'm just annoyed that the research on soy drums it up like this and like that and it's hard to find anything informative and objective.

I did find two papers which are contradicting each other. None of them were done in humans, which even further reduces their value:

Studies on the oestrogenic activity of soybean oil on albino rats. elSattar ElBaltran SA. Boll Chim Farm 2001 Mar-Apr;140(2):119-24

The oestrogenic activity of soybean oil was studied biologically by vaginal epithelium cornification and the uterine weight method. A significant increase in vaginal cornification was found in ovariectomized adult rats given soybean oil orally for five days resulting an oestrogenic like activity for the soybean oil. Also, using the uterine weight method in immature and ovariectomized rats, the administration of either oestradiol or soybean oil induced a significant increase in the uterine weight. These results indicated that the effect of soybean oil has an oestrogenic like activity equal to 0.6 that activity of oestradiol. Furthermore, with respect to body weight the administration of either oestradiol or soybean oil showed insignificant change than the initial body weight. These findings suggest that soybean oil exerts an oestrogenic like effect.

Lack of oestrogen-like activity in commercially refined vegetable oils. Bieber MA. Food Chem Toxicol 1986 Mar;24(3):251-3

Commercially refined corn, safflower, sunflower and soya-bean oils, as well as well as lard and beef tallow, were fed to pre-pubertal female mice at a level of 5 or 20% of a semi-synthetic diet to assess whether they exhibited any oestrogen-like activity, as measured by changes in uterine weight or in the ratio of uterine weight to body weight. No measurable oestrogen-like activity was observed, in contrast to the effects in positive-control animals treated with 5, 10 or 15 ppb diethylstilboestrol. This finding contradicts an earlier report in the literature. It also shows that oestrogen-like activity in a commercially refined oil is not likely to be a variable in the complex mechanism of the dietary modulation of induced breast-tumour growth.

Neither study was done on humans or has a complete specification of quantity and duration of the diets. I've not read the full texts of these yet.

By the way, if any of yous are interested in being a nerd like me and do MedLine searches, go nuts:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed

[Iron Bull]

Thanks west on 46 for the great info. Good stuff!:thup: