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Emperor G_D

Soy: to bean or not to bean?

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Hmmm.

 

12 weeks may have been too short to see significant hormonal effects.

 

There is a huge body of data that shows soy to be both directly estrogenic and to increase the production of s-equol, a potent estrogen lignan, from gut bacteria in humans...I'd steer clear of it given that there are so many other sources of protein that do not carry soy's estrogenic baggage.

 

 

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Tangentially related, I liked this quote:

 

"Although they are structurally similar to anthropogenic endocrine-disrupting compounds (EDC) and behave similarly on numerous molecular and cellular targets, intake of soya phyto-oestrogens is broadly encouraged and regarded as healthy, while their synthetic counterparts are increasingly viewed with caution and met with repeated calls to ban or restrict their use. This attitudinal discordance is almost entirely based on the source of the compounds (soya is ‘natural’, while synthetic chemicals are not) rather than the scientific evidence regarding their hormone-disrupting activities."

 

source

 

People go nuts over estrogenic compounds like bisphenol-A in plastic bottles but many of those same people buy and consume soy and flax "milk" by the liter....

 

 

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3 hours ago, STENDEC said:

People go nuts over estrogenic compounds like bisphenol-A in plastic bottles but many of those same people buy and consume soy and flax "milk" by the liter....

 

I do hear that natural vs synthetic discussion among the less scientifically literate crowd.

One difference between BPA and soy is the issue of choice -- soy ingestion in quantity is generally a voluntary act. However BPA et al. is present in many kinds of packaging in stealth mode.

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Soy is estrogenic...no way around it

 

Soy diets might increase women's bone strength

Science News
August 7, 2018

Osteoporosis, decreased physical activity and weight gain are serious health concerns for postmenopausal women. Researchers from the University of Missouri now have discovered through a new animal study that soy protein found in food might counter the negative effects of menopause on bone and metabolic health. Moreover, the researchers believe that soy protein might also have positive impacts on bone strength for women who have not yet reached menopause.

 

"The findings suggest that all women might see improved bone strength by adding some soy-based whole foods, such as tofu and soy milk, to their diet," said Pamela Hinton, professor of nutrition and exercise physiology. "We also believe that soy-based diets can improve metabolic function for postmenopausal women."

 

Hinton and Victoria Vieira-Potter, co-author and associate professor of nutrition and exercise physiology, studied the effects of soy versus corn-based diets on rats selectively bred to have low fitness levels. Rats were again divided between those with and without ovaries to mimic effects of menopause. Prior research has found that these rats are good models for menopausal women. They compared the impact of the soy diet on bone strength and metabolic function to rats fed a corn-based, soy-free diet.

 

"Prior research has shown that these rats are good models, as average American women are relatively inactive both before, and especially after, menopause," Vieira-Potter said. "As such, understanding how dietary protein sources, such as soy, can impact metabolism and bone health in these rats can help us better understand how such diets might impact women's health across the lifespan."

 

The researchers found that the tibia bones of the rats that were fed soy were stronger compared to the rats who were fed the corn-based diet, regardless of ovarian hormone status. Moreover, they found that the soy-based diet also improved metabolic function of the rats both with and without ovaries.

 

"Bottom line, this study showed that women might improve bone strength by adding some soy-based whole foods to their diet," Hinton said. "Our findings suggest that women don't even need to eat as much soy as is found in typical Asian diets, but adding some tofu or other soy, for example foods found in vegetarian diets, could help strengthen bones."

 

Journal Reference:

Pamela S. Hinton, Laura C. Ortinau, Rebecca K. Dirkes, Emily L. Shaw, Matthew W. Richard, Terese Z. Zidon, Steven L. Britton, Lauren G. Koch, Victoria J. Vieira-Potter. Soy protein improves tibial whole-bone and tissue-level biomechanical properties in ovariectomized and ovary-intact, low-fit female rats. Bone Reports, 2018; 8: 244 DOI: 10.1016/j.bonr.2018.05.002
 

 

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I did some reading on this over the weekend and came across this review:

 

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5188409/

 

Section 16 was particularly interesting:

 

"Two case reports describing feminizing effects that allegedly occurred as a result of soyfood consumption have been published [389,390]. However, in both cases the individuals were said to have consumed 360 mg/day isoflavones (~9-fold greater than the mean intake among older Japanese men) in the context of unbalanced and likely nutrient-deficient diets since soyfoods accounted for the vast majority of calories consumed. Furthermore, in contrast to the rise in circulating estrogen levels noted in one case [389], no effects on estrogen levels have been noted in numerous clinical studies in which men were exposed to as much as 150 mg/day isoflavones [391].

Similarly, the drop in testosterone levels noted in the other case [390] is as already noted, inconsistent with the preponderance of the clinical data showing neither soy nor isoflavone supplements affect testosterone levels [283]. More specifically, a systematic review and meta-analysis that included 15 placebo-controlled treatment groups with baseline and ending measures and an additional 32 reports involving 36 treatment groups found no effects of soy protein or isoflavone intake on testosterone, sex hormone binding globulin, free testosterone or the free androgen index [283]. Studies published subsequent to this meta-analysis have reached similar conclusions [168,392,393,394]. The two aforementioned case reports simply illustrate that consuming excessive amounts of essentially any food can potentially lead to abnormalities [389,390]."

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This study yields a handy dose calculator for soy protein.

 

Nutr Cancer. 2006;55(1):1-12.
Estimated Asian adult soy protein and isoflavone intakes.
Messina M1, Nagata C, Wu AH.

There is substantial interest in the possible anticancer effects of soy foods. In part, this is because of the historically low incidence rates of breast and prostate cancer in Asia. Of the several putative soybean chemopreventive agents, isoflavones have received the most attention. Awareness of this research has led increasing numbers of consumers to use soy foods, isoflavone-fortified foods, and isoflavone supplements. Therefore, there is a need for guidance regarding appropriate isoflavone intake levels. To this end, this article analyzed soy protein (as a surrogate for isoflavones) and isoflavone intake of the major soy food-consuming countries using individual dietary surveys for the bulk of the information. In total, 24 surveys from 4 countries that met the inclusion criteria were identified: Japan (n = 11), China (n = 7), Hong Kong (n = 4), and Singapore (n = 2). The results indicate that older Japanese adults consume approximately 6-11 g of soy protein and 25-50 mg of isoflavones (expressed as aglycone equivalents) per day. Intake in Hong Kong and Singapore is lower than in Japan, whereas significant regional intake differences exist for China. Evidence suggests that < or =10% of the Asian population consumes as much as 25 g of soy protein or 100 mg of isoflavones per day. The applicability of these findings for making soy intake recommendations for non-Asians is discussed.

 

PMID: 16965235

 

So for your typical tofu-eating vegetarian, the amount of isoflavone they get might be fairly minimal but for a bodybuilder supplementing his diet with soy protein shakes, getting 4-500mg of isoflavone a day might not be unexpected.

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http://cebp.aacrjournals.org/content/16/4/829.long

 

...Soy protein powder decreases serum testosterone levels in healthy men and acts as an ER-β agonist...

...mean age of 32.25 years (range 25 to 47). Serum testosterone decreased 19%(±22%) during the 4-week use of soy protein powder (P = 0.021)....

 

 

https://www.ncbi.nlm.nih.gov/pubmed/24015701

 

...14 days of supplementation with soy protein does appear to partially blunt serum testosterone....

 

 

https://academic.oup.com/jn/article/135/3/584/4663709

 

...dihydrotestosterone (DHT) and DHT/testosterone were significantly decreased by the low-iso SPI [9.4% (P = 0.036) and 9.0% (P = 0.004), respectively] and the high-iso SPI [15% (P = 0.047) and 14% (P = 0.013), respectively], compared with the MPI at d 57....

...Estradiol and estrone levels were significantly increased following consumption of the low-iso SPI relative to the MPI at d 57...

 

 

----

 

...I will continue

 

.

 

.

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We've seen elsewhere that whey increases MPS more when compared to soy but this is the first I've seen that it also apparently increases muscle satellite cell counts which may indicate that whey protein is not only promoting hypertrophy but also hyperplasia.

 

Nutrients. 2017 Sep 4;9(9). pii: E972. doi: 10.3390/nu9090972.
Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males.
Mobley CB1, Haun CT2, Roberson PA3, Mumford PW4, Romero MA5, Kephart WC6, Anderson RG7, Vann CG8, Osburn SC9, Pledge CD10, Martin JS11,12, Young KC13,14, Goodlett MD15,16, Pascoe DD17, Lockwood CM18, Roberts MD19,20.

We sought to determine the effects of L-leucine (LEU) or different protein supplements standardized to LEU (~3.0 g/serving) on changes in body composition, strength, and histological attributes in skeletal muscle and adipose tissue. Seventy-five untrained, college-aged males (mean ± standard error of the mean (SE); age = 21 ± 1 years, body mass = 79.2 ± 0.3 kg) were randomly assigned to an isocaloric, lipid-, and organoleptically-matched maltodextrin placebo (PLA, n = 15), LEU (n = 14), whey protein concentrate (WPC, n = 17), whey protein hydrolysate (WPH, n = 14), or soy protein concentrate (SPC, n = 15) group. Participants performed whole-body resistance training three days per week for 12 weeks while consuming supplements twice daily. Skeletal muscle and subcutaneous (SQ) fat biopsies were obtained at baseline (T1) and ~72 h following the last day of training (T39). Tissue samples were analyzed for changes in type I and II fiber cross sectional area (CSA), non-fiber specific satellite cell count, and SQ adipocyte CSA. On average, all supplement groups including PLA exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual X-ray absorptiometry (+2.2 kg; time p = 0.024) and type I and II fiber CSA increases (+394 μm² and +927 μm²; time p < 0.001 and 0.024, respectively). Notably, all groups reported increasing Calorie intakes ~600-800 kcal/day from T1 to T39 (time p < 0.001), and all groups consumed at least 1.1 g/kg/day of protein at T1 and 1.3 g/kg/day at T39. There was a training, but no supplementation, effect regarding the reduction in SQ adipocyte CSA (-210 μm²; time p = 0.001). Interestingly, satellite cell counts within the WPC (p < 0.05) and WPH (p < 0.05) groups were greater at T39 relative to T1. In summary, LEU or protein supplementation (standardized to LEU content) does not provide added benefit in increasing whole-body skeletal muscle mass or strength above PLA following 3 months of training in previously untrained college-aged males that increase Calorie intakes with resistance training and consume above the recommended daily intake of protein throughout training. However, whey protein supplementation increases skeletal muscle satellite cell number in this population, and this phenomena may promote more favorable training adaptations over more prolonged periods.

 

PMID: 28869573 

 

FFT

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.

 

 

Isoflavone-Rich Soy Protein Isolate Suppresses Androgen Receptor Expression 

https://academic.oup.com/jn/article/137/7/1769/4664529

 

Dietary supplements of soya flour lower serum testosterone concentrations

https://www.nature.com/articles/1601495

 

Inverse Association of Soy Product Intake With Serum Androgen and Estrogen Concentrations in Japanese Men

https://www.tandfonline.com/doi/abs/10.1207/S15327914NC3601_3?journalCode=hnuc20

 

Potential detrimental effect of soy isoflavones on testis sertoli cell

http://www.csumed.org/xbwk/fileup/PDF/201406598.pdf

 

Genistein decreases androgen biosynthesis in rat Leydig cells by interference with luteinizing hormone-dependent signaling

https://www.sciencedirect.com/science/article/pii/S0378427408013350?via%3Dihub

 

Dietary soy-phytoestrogens decrease testosterone levels and prostate weight without altering LH, prostate 5-reductase or testicular steroidogenic acute regulatory peptide levels in adult male Sprague–Dawley rats

http://joe.endocrinology-journals.org/content/170/3/591.long

 

Genistein down-regulates androgen receptor by modulating HDAC6-Hsp90 chaperone function

http://mct.aacrjournals.org/content/7/10/3195.long

 

Soy, phyto‐oestrogens and male reproductive function: a review

https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2605.2009.01011.x

...caution would suggest that perinatal phyto‐oestrogen exposure, such as that found in infants feeding on soy‐based formula, should be avoided...

 

.

 

 

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On 10/8/2018 at 5:25 AM, STENDEC said:

We've seen elsewhere that whey increases MPS more when compared to soy but this is the first I've seen that it also apparently increases muscle satellite cell counts which may indicate that whey protein is not only promoting hypertrophy but also hyperplasia.

 

Nutrients. 2017 Sep 4;9(9). pii: E972. doi: 10.3390/nu9090972.
Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males.
Mobley CB1, Haun CT2, Roberson PA3, Mumford PW4, Romero MA5, Kephart WC6, Anderson RG7, Vann CG8, Osburn SC9, Pledge CD10, Martin JS11,12, Young KC13,14, Goodlett MD15,16, Pascoe DD17, Lockwood CM18, Roberts MD19,20.

We sought to determine the effects of L-leucine (LEU) or different protein supplements standardized to LEU (~3.0 g/serving) on changes in body composition, strength, and histological attributes in skeletal muscle and adipose tissue. Seventy-five untrained, college-aged males (mean ± standard error of the mean (SE); age = 21 ± 1 years, body mass = 79.2 ± 0.3 kg) were randomly assigned to an isocaloric, lipid-, and organoleptically-matched maltodextrin placebo (PLA, n = 15), LEU (n = 14), whey protein concentrate (WPC, n = 17), whey protein hydrolysate (WPH, n = 14), or soy protein concentrate (SPC, n = 15) group. Participants performed whole-body resistance training three days per week for 12 weeks while consuming supplements twice daily. Skeletal muscle and subcutaneous (SQ) fat biopsies were obtained at baseline (T1) and ~72 h following the last day of training (T39). Tissue samples were analyzed for changes in type I and II fiber cross sectional area (CSA), non-fiber specific satellite cell count, and SQ adipocyte CSA. On average, all supplement groups including PLA exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual X-ray absorptiometry (+2.2 kg; time p = 0.024) and type I and II fiber CSA increases (+394 μm² and +927 μm²; time p < 0.001 and 0.024, respectively). Notably, all groups reported increasing Calorie intakes ~600-800 kcal/day from T1 to T39 (time p < 0.001), and all groups consumed at least 1.1 g/kg/day of protein at T1 and 1.3 g/kg/day at T39. There was a training, but no supplementation, effect regarding the reduction in SQ adipocyte CSA (-210 μm²; time p = 0.001). Interestingly, satellite cell counts within the WPC (p < 0.05) and WPH (p < 0.05) groups were greater at T39 relative to T1. In summary, LEU or protein supplementation (standardized to LEU content) does not provide added benefit in increasing whole-body skeletal muscle mass or strength above PLA following 3 months of training in previously untrained college-aged males that increase Calorie intakes with resistance training and consume above the recommended daily intake of protein throughout training. However, whey protein supplementation increases skeletal muscle satellite cell number in this population, and this phenomena may promote more favorable training adaptations over more prolonged periods.

 

PMID: 28869573 

 

FFT

 

 

absolutely no soy

 

Whey protein supplementation during resistance training augments lean body mass

 

https://www.tandfonline.com/doi/abs/10.1080/07315724.2013.793580

 

Daily protein intake (including the supplement) for carb, whey, and soy was 1.1, 1.4, and 1.4 g·kg body mass⁻¹, respectively. Lean body mass gains were significantly (p < 0.05) greater in whey (3.3 ± 1.5 kg) than carb (2.3 ± 1.7 kg) and soy (1.8 ± 1.6 kg). Fat mass 

 

.

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Psychopharmacology (Berl). 2003 Apr;167(1):46-53. Epub 2003 Mar 5.
The soya isoflavone content of rat diet can increase anxiety and stress hormone release in the male rat.
Hartley DE1, Edwards JE, Spiller CE, Alom N, Tucci S, Seth P, Forsling ML, File SE.


RATIONALE:
Most commercial rodent diets are formulated with soya protein and therefore contain soya isoflavones. Isoflavones form one of the main classes of phytoestrogens and have been found to exert both oestrogenic and anti-oestrogenic effects on the central nervous system. The effects have not been limited to reproductive behaviour, but include effects on learning and anxiety and actions on the hypothalamo-pituitary axis. It is therefore possible that the soya content of diet could have significant effects on brain and behaviour and be an important source of between-laboratory variability.

 

OBJECTIVES:
To determine whether behaviour in two animal tests of anxiety, and stress hormone production, would differ between rats that were fed a diet which was free of soya isoflavones and other phytoestrogens (iso-free) and those that were fed a diet which contained 150 microg/g of the isoflavones genistein and daidzein (iso-150). This controlled diet has an isoflavone concentration similar to that in the maintenance diet routinely used in our institution.

 

METHODS:
Male rats were randomly allocated to the iso-free and iso-150 diets and their body weights and food and water consumption were recorded for 14 days. They were then maintained on the same diets, but housed singly for 4 days, before testing in the social interaction and elevated plus-maze tests of anxiety. Corticosterone concentrations in both dietary groups were determined under basal conditions and after the stress of the two tests of anxiety. Vasopressin and oxytocin concentrations were determined after brief handling stress.

 

RESULTS:
The groups did not differ in food or water intake, body weight or oxytocin concentrations. Compared with the rats fed the iso-free diet, the rats fed the iso-150 diet spent significantly less time in active social interaction and made a significantly lower percentage of entries onto the open arms of the plus-maze, indicating anxiogenic effects in both animal tests. The groups did not differ in their basal corticosterone concentrations, but the iso-150 group had significantly elevated stress-induced corticosterone concentrations. Stress-induced plasma vasopressin concentrations were also significantly elevated in the iso-150 diet group compared with the iso-free rats.

 

CONCLUSIONS:
Major changes in behavioural measures of anxiety and in stress hormones can result from the soya isoflavone content of rat diet. These changes are as striking as those seen following drug administration and could form an important source of variation between laboratories.

 

PMID: 12618915 

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Interestingly, one Chinese study shows daidzein is anxiolytic in male rats, though it makes them wimps (lower aggression and mating)

https://www.sciencedirect.com/science/article/pii/S009130571000095X?via%3Dihub

 

And another shows genestein is anxiolytic

https://www.sciencedirect.com/science/article/pii/S0165178117301646?via%3Dihub

 

But I rather doubt that Chinese research on soy is untainted by commercial interests.

"In 2015, of the 50 top soybean companies, around half produced tofu (utilizing 350,700 tons of Non-GM soybeans), 16 produced dried soy curd (utilizing 247,600 tons), 7 produced soy milk (utilizing 80,800 tons) and soy milk powder (utilizing 230,300 tons), and the rest produced soybean paste and sauce (China Soybean Association)." http://atlanticgrainscouncil.ca/wp/wp-content/uploads/2017/03/China-Market-Research-Report.pdf

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