is soy milk ok?

[lols]

i tried to do a search on this topic, but didnt come up with much.

is there any research that indicates that drinking soy milk is bad for women? Ive heard its not recommended for men - but if consumed daily - does this do any harm?

ive been having a cup before training in the early am and have it in a takeaway coffee mid morning.

[LOGAN]

show me this article....i dont see how it would be bad for anyone....i use SILK and buy it in bulk from sams....sometimes ill make a protein shake with the vanilla flavored stuff...it tatstes rather well and adds some soy protein to the mix

[Puddles]

There are conflicting thoughts on the benefits/risks of using soy.

http://web.aces.uiuc.edu/faq/faq.pdl...d=5&faq_id=969

http://www.personalconsult.com/artic...ehormones.html

http://www.drlam.com/opinion/soyandestrogen.cfm

http://www.mothering.com/articles/gr...soy_story.html


And this is kinda weird but my cat is not picky however he will not drink soy milk. It's one of the few things he will turn down. Makes me wonder if he knows something I don't.

[liftsiron]

Soy protein while looking good on paper is onlly about 35% digestable. Soy normally contains plant estrogens which may lead to weight gain, mood swings etc. Studies on soy and thyroid function show that as little as 30 grams of soy protein per day may really screw up that organ. Sometimes requireing medication for life.

[Voodoo]

Aisans have been using soy for centuries. And they don't seem to have a problem.

[lols]

Originally Posted by liftsiron

Soy protein while looking good on paper is onlly about 35% digestable. Soy normally contains plant estrogens which may lead to weight gain, mood swings etc. Studies on soy and thyroid function show that as little as 30 grams of soy protein per day may really screw up that organ. Sometimes requireing medication for life.

this is interesting.. do you have info to back it up?

[Mr.X]

Soy protein has good and bad properties.

On islands in japan, women live until 120y/o with soy and fiber in their diet.

lols, I wouldn't worry about adding soy to your diet as a woman. Men on the other hand should stay away from soy.

[liftsiron]

Originally Posted by Voodoo

Aisans have been using soy for centuries. And they don't seem to have a problem.

How would you know, I would bet 90% of Aisa's population never see a real doctor.

[liftsiron]

Originally Posted by lols

this is interesting.. do you have info to back it up?

Goitrogenic and Estrogenic Activity of Soy Isoflavones



Daniel R. Doerge1 and Daniel M. Sheehan2
1Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, Arkansas, USA; 2Daniel M. Sheehan and Associates, Little Rock, Arkansas, USA



Abstract

Soy is known to produce estrogenic isoflavones. Here, we briefly review the evidence for binding of isoflavones to the estrogen receptor, in vivo estrogenicity and developmental toxicity, and estrogen developmental carcinogenesis in rats. Genistein, the major soy isoflavone, also has a frank estrogenic effect in women. We then focus on evidence from animal and human studies suggesting a link between soy consumption and goiter, an activity independent of estrogenicity. Iodine deficiency greatly increases soy antithyroid effects, whereas iodine supplementation is protective. Thus, soy effects on the thyroid involve the critical relationship between iodine status and thyroid function. In rats consuming genistein-fortified diets, genistein was measured in the thyroid at levels that produced dose-dependent and significant inactivation of rat and human thyroid peroxidase (TPO) in vitro. Furthermore, rat TPO activity was dose-dependently reduced by up to 80%. Although these effects are clear and reproducible, other measures of thyroid function in vivo (serum levels of triiodothyronine, thyroxine, and thyroid-stimulating hormone; thyroid weight; and thyroid histopathology) were all normal. Additional factors appear necessary for soy to cause overt thyroid toxicity. These clearly include iodine deficiency but may also include additional soy components, other defects of hormone synthesis, or additional goitrogenic dietary factors. Although safety testing of natural products, including soy products, is not required, the possibility that widely consumed soy products may cause harm in the human population via either or both estrogenic and goitrogenic activities is of concern. Rigorous, high-quality experimental and human research into soy toxicity is the best way to address these concerns. Similar studies in wildlife populations are also appropriate. Key words: estrogen toxicity, estrogenicity, genistein, isoflavones, mass spectrometry, soy, thyroid peroxidase, thyroid toxicity. Environ Health Perspect 110(suppl 3):349-353 (2002).

[liftsiron]

New Findings May Support Soy-Dementia in Men


August 9, 2003 - Ian Williams Goddard

In April 2000, Lon White and others reported a dose-dependent positive correlation between tofu consumption and brain atrophy in a large sample of men over several decades. [1] While correlation does not prove causation, study size and duration along with the robust dose-dependent relationship caused me, even as a vegetarian, to avoid tofu and other soy products.

Correlation-based hypotheses should be tested against the availability of possible causal mechanisms. In addition to possible causal mechanisms previously cited by this author, [2] recent findings significantly increase the case for a causal mechanism of soy-induced brain atrophy.

Atrophic Pharmacology Indicated

Brain-derived neurotrophic factor (BDNF) facilitates the survival and genesis of brain cells. [3,4] The neuroprotective effects of caloric restriction are attributed in part to increased BDNF. [5] On the other hand, reduced BDNF is known to cause brain-cell atrophy and is associated with Alzheimer’s disease. [6,7] Now, a study in "Neuroscience Letters" reports that soy significantly reduced BDNF in the hippocampus and cerebral cortex of male rats. [8] Since reduced BDNF can cause neural atrophy, these findings appear to provide compelling evidence for a causal mechanism that might explain the positive correlation between tofu (soy) consumption and brain atrophy reported by White et al. [1]

Bad For Boys, Good For Girls?

While soy appears to reduce BDNF in male rats, it has also been shown to increase BDNF in female rats. [9] In fact, soy appears to affect neurological parameters in a sex-defined fashion wherein females benefit and males suffer. [10-13] There is little doubt among researchers that this is because soy is high in phytoestrogens, which are plant-derived substances that act like the female hormone estrogen.

However, that sex-defined difference fails to explain the findings regarding the wives of male subjects in White et al., who reported: "A similar association of midlife tofu intake with poor late life cognitive test scores was also observed among wives of cohort members, using the husband’s answers to food frequency questions as proxy for the wife’s consumption." [1] White et al. proposed that long-term consumption of weaker soy estrogens may displace the body’s own stronger estrogen along with its benefits.

Evidence Against Soy-Dementia Hypothesis?

A possible signal contrary to a soy-dementia link is the low prevalence of dementia [14] and high consumption of soy in Okinawa, Japan. [15] However, that negative correlation, like any correlation, does not prove causation. For example, perhaps soy does cause dementia but other factors in Okinawa offset the effect.

Also, White et al. explored correlations of a range of foods to neurological parameters, whereas this Okinawa analysis is a sweeping generalization of only tofu to all of Okinawa. In other words, it stands to reason that the study by White et al. finding a positive tofu-dementia correlation has the greater likelihood of providing the more accurate picture. Nevertheless, in my view this Okinawa data warrants further examination as a possible route to falsifying the soy-dementia hypotheses.

In closing, the findings of soy-induced BDNF reduction in male rat brain regions that are central to the onset of dementia, in addition to previous findings, [2] appear to provide compelling evidence of a possible causal mechanism that might explain the soy-dementia correlation reported by White et al. [1] Obviously further research is necessary before a clear picture emerges regarding the effects of long-term soy consumption on the brain. But in the meantime, my inclination is to play it safe and avoid soy.


--------------------------------------------------------------------------------

References

White et al.: "In this population, higher midlife tofu consumption was independently associated with indicators of cognitive impairment and brain atrophy in late life."
Goddard (scroll to): "Is There Reason to Believe Tofu May Cause Brain Atrophy?"
Korte M: "Neurotrophic factors have long been known to promote neuronal survival and differentiation."
J Neurochem (Sep 2002): "These findings suggest that BDNF plays an important role in the regulation of the basal level of neurogenesis in dentate gyrus of adult mice [...]."
Endocrinology (Jun 2003): "Recent studies have shown that DR [dietary restriction] stimulates the production of brain-derived neurotrophic factor (BDNF) in brain cells, which may mediate neuroprotective and neurogenic actions of DR."
Arch Gen Psychiatry (Jul 1997): "stress can decrease the expression of brain-derived neurotrophic factor and lead to atrophy of these same populations of stress-vulnerable hippocampal neurons."
Brain Res Mol Brain Res (Oct 3, 1997): "a reduction in BDNF mRNA expression has been observed in human post-mortem Alzheimer’s disease hippocampi. [...] These results support and extend previous findings that BDNF mRNA is reduced in the human Alzheimer’s disease hippocampus and temporal cortex, and suggest that loss of BDNF may contribute to the progressive atrophy of neurons in Alzheimer’s disease."
Neurosci Lett (Feb 27, 2003): "significant reductions were found in brain-derived neurotrophic factor (BDNF) mRNA expression in the CA3 and CA4 region of the hippocampus and in the cerebral cortex in the [male] rats fed the diet containing phytoestrogens, compared with those on the soya-free diet."
Neurosci Lett (Feb 1999): "soy phytoestrogens significantly increased the mRNA levels of BDNF [...in] female rats."
Neurotoxicol Teratol (Jan-Feb 2002): "when learning and memory parameters were examined in a radial arm maze testing visual-spatial memory (VSM), the diet treatments significantly changed the typical sexually dimorphic pattern of VSM. Specifically, adult Phyto-rich fed females outperformed Phyto-free fed females, while in males on the same diets, the opposite pattern of maze performance was observed."
BMC Neurosci (2001 2(1):20): "Female rats receiving lifelong exposure to a high-phytoestrogen containing diet (Phyto-600) acquired the maze faster than females fed a phytoestrogen-free diet (Phyto-free); in males the opposite diet effect was identified. [...] These findings suggest that dietary soy derived phytoestrogens can influence learning and memory and alter the expression of proteins involved in neural protection and inflammation in rats."
BMC Neurosis (2001 2(1):21): "When a diet change was initiated in adulthood, control phytoestrogen-rich fed females outperformed control females switched to a phytoestrogen-free diet. Whereas, in control males the opposite diet effect was identified."
Neurosci Lett (May 15, 2003): "This study is the first to show that lifelong consumption of dietary phytoestrogens alters the HPA stress response in male rats."
Dementia Rates in Okinawa vs Japan & US.
Soy Phytochemical Intake in Okinawa.