# Soy Protein Isolate



## akadon (Apr 12, 2014)

Anyone else taking Honeyville Soy Protein Isolate? A 4lb bag has 24g of protein per oz. Has anyone had *personal experience* with Soy Protein Isolate?


----------



## exerciseordie (Apr 12, 2014)

I can tell you that soy is def not optimal due to the amino acid profile. Whey is far better


----------



## Oldschool (Apr 13, 2014)

Why not take the money you would spend on soy and buy some real food. Like beef. It has a superior amino acid profile and ZINC which you may be deficient in. Good luck.


----------



## Anthony Tate (Apr 14, 2014)

I think its pretty decent.


----------



## akadon (Apr 14, 2014)

OldSkool said:


> Why not take the money you would spend on soy and buy some real food. Like beef. It has a superior amino acid profile and ZINC which you may be deficient in. Good luck.



I plan on eating both, but was interested supplementing a small portion (about 1/4 to 1/3) of my daily protein needs. Soy protein seems to be the least expensive and very affordable. It would be 1,555 grams of protein for $24.


----------



## akadon (Apr 14, 2014)

I'm surprised that no one else has any experience with using soy protein...


----------



## dave 236 (Apr 14, 2014)

Soy protein is cheap because its awful. Its also not a particularly good choice for males. Its a phyto-estrogen. Just do some research.  Beef, chicken, fish, and eggs are great and supplement with whey or a whey egg protein blend. All of those give more bang for the buck than soy and taste better.

Sent from my DROID RAZR HD using Tapatalk


----------



## Mincow (Apr 14, 2014)

Everything I've read places soy protein on the bottom end of protein choices.  There are several better sources as many listed above.


----------



## flood (Apr 16, 2014)

akadon said:


> I'm surprised that no one else has any experience with using soy protein...


I avoid all soy. I wrecks testosterone.


----------



## theCaptn' (Apr 16, 2014)

Collagen protein. Thank me later.


----------



## Uplifted (Apr 16, 2014)

Soy protein = bitch tits


----------



## akadon (Apr 16, 2014)

Uplifted said:


> Soy protein = bitch tits



protein is protein just like a calorie is a calorie no matter it's source correct?


----------



## orange24 (Apr 17, 2014)

No


----------



## Dale Mabry (Apr 17, 2014)

akadon said:


> protein is protein just like a calorie is a calorie no matter it's source correct?



No.  Aside from the poor amino acid profile, soy contains trypsin inhibitors which block protein degrading enzymes.  If you don;t fully digest protein, you don't absorb it.  There was a study a while back that showed eating soy even lowers the bioavailability of other protein sources you consume with it because they don't get broken down.

Here's a good rundown from John Kiefer on soy.

http://articles.elitefts.com/nutrition/soy-the-protein-killer/


----------



## Kenny Croxdale (Apr 17, 2014)

exerciseordie said:


> I can tell you that soy is def not optimal due to the amino acid profile. Whey is far better



*Not True*

Soy is higher in...

1) Glutamine

2) Branch Chain Amino Acids (Leucine/Isoluecine/Valine

3) Argenine

Kenny Croxdale


----------



## Kenny Croxdale (Apr 17, 2014)

flood said:


> I avoid all soy. I wrecks testosterone.



*Misconception*

Like you, I've heard this forever and never used it. 

However, the research indicates that isn't true. 

*Whey vs. Soy -- You've Been Tricked*
http://www.timinvermont.com/fitness/soyvswhy.htm

"Animal research suggests some great advantages of using soy protein isolate as a bodybuilding supplement. Research has shown that the isoflavone daidzein found in soy-protein isolate might have a gender specific normalizing effect on sex-hormone production. Lab animals experienced testosterone and growth hormone excretion as well as muscle growth in males, while the female animals experienced a decrease in these hormones and fat loss."

*Soy Vs. Whey* 

"The latest studies into soy protein suggest it does not decrease testosterone and raise estrogen, as previously thought."

"... the American College of Sports Medicine (ACSM) Meeting, May 2004, and sponsored by the US National Dairy Council, found the post-workout consumption of isonitrogenous and isoenergetic soy drink to be statistically significant in hastening mass, fat-bone free mass (FBFM) and increases in strength..."

Soy's Amino Acid Profile

1) Soy is higher in Arginine than Whey.

2) Soy is higher in Glutamine than Whey

"Arginine is well known as a stimulant of anabolic hormones that stimulate muscle formation, while glutamine is considered essential during metabolic stress."http://www.bodybuilding.com/fun/drobson71.htm

*Synergistic Protein Stack*

Synergistic: The sum is greater than the individual parts. 

Synergistic Example: 2 + 2 = 5

What research shows is that combining two proteins with different amino acid profiles, magnifies the effetiveness.

"Used together in an exercise regimen, soy and whey proteins complement each other well. Whey protein, as mentioned, is high in branched chain amino acids, used as an important energy source by the body during exercise, while soy protein has high amounts of the amino acids arginine and glutamine."

*Another Look*

The best thing to do is review the information posted above, do your own research and come to you own conclusions.

As for me, Soy Isolate appears to have some definite strength.  Even better is the low cost of it.

Kenny Croxdale


----------



## theCaptn' (Apr 17, 2014)

Who knows what's true or not. Eat more meat I say.


----------



## akadon (Apr 17, 2014)

Dale Mabry said:


> No.  Aside from the poor amino acid profile, soy contains trypsin inhibitors which block protein degrading enzymes.  If you don;t fully digest protein, you don't absorb it.  There was a study a while back that showed eating soy even lowers the bioavailability of other protein sources you consume with it because they don't get broken down.
> 
> Here's a good rundown from John Kiefer on soy.
> 
> http://articles.elitefts.com/nutrition/soy-the-protein-killer/



Thanks for bringing "trypsin" to my attention. From what I just read, when soy is fermented or heat treated, trypsin levels become severely depleted. Soy protein isolate is heat treated I believe.


----------



## Dale Mabry (Apr 17, 2014)

akadon said:


> Thanks for bringing "trypsin" to my attention. From what I just read, when soy is fermented or heat treated, trypsin levels become severely depleted. Soy protein isolate is heat treated I believe.



It should be heat treated, not sure for how long though and it may vary by manufacturer.  My concern would be in relying on SPI as the primary source of protein.  You will remove 80-90% of the TIAs from heating it properly but having 3-4 servigns a day could impact protein digestibility significantly.  I wouldn't worry about this so much from a gains perspective because most BBers overeat protein anyway.  What I would be concerned with is fucking up your gut bacteria.  You aren't supposed to have large amounts of undigested protein in your colon.  This is the problem with gluten, we don't digest it very well and it can fuck up your microbiota.  This is also why gluten and legumes such as soy and peanuts tend to be immunogenic, 80% of your immune system is housed in your gut.


----------



## akadon (Apr 18, 2014)

Dale Mabry said:


> It should be heat treated, not sure for how long though and it may vary by manufacturer.  My concern would be in relying on SPI as the primary source of protein.  You will remove 80-90% of the TIAs from heating it properly but having 3-4 servigns a day could impact protein digestibility significantly.  I wouldn't worry about this so much from a gains perspective because most BBers overeat protein anyway.  What I would be concerned with is fucking up your gut bacteria.  You aren't supposed to have large amounts of undigested protein in your colon.  This is the problem with gluten, we don't digest it very well and it can fuck up your microbiota.  This is also why gluten and legumes such as soy and peanuts tend to be immunogenic, 80% of your immune system is housed in your gut.



Yea, I've been doing a lot of reading, and just read about soy containing phytates which affects the gastrointestinal tract. While I believe that the estrogen effects on humans is bull and that most of soy's anti-nutrients are dropped to a safe level during fermentation, I'm not sure and decided not to risk taking SPI as I do not know and can not be 100% sure what's left in it or how it was prepaid.


----------



## Dale Mabry (Apr 19, 2014)

You don't really need to worry about phytates because they do not bind minerals, they are already bound to them in whatever you are eating.  I agree the estrogenic effect is likely overstated, my primary concern with soy is that we don't break it down very well.  Now, if it's hydrolyzed, it doesn't really concern me as much.


----------



## akadon (Apr 19, 2014)

Dale Mabry said:


> You don't really need to worry about phytates because they do not bind minerals, they are already bound to them in whatever you are eating.  I agree the estrogenic effect is likely overstated, my primary concern with soy is that we don't break it down very well.  Now, if it's hydrolyzed, it doesn't really concern me as much.









I just decided to buy 10 lbs of Whey protein. It cost A LOT more than I can really afford on a regular basis, but there are too many unknowns when it comes to buying soy. I can't be to sure what's in it and how certain brands prepared it. Thanks for all the useful info.


----------



## Dale Mabry (Apr 20, 2014)

Whey is pretty good and fast absorbing.  I used to be more about blends, but I don't eat casein anymore so the only blend I would use is whey/egg.  Although, at this point I get all of my protein from food.


----------



## theCaptn' (Apr 20, 2014)

Whey concentrate has all the nutrients in it still.


----------



## flood (Apr 20, 2014)

Dale Mabry said:


> Whey is pretty good and fast absorbing.  I used to be more about blends, but I don't eat casein anymore so the only blend I would use is whey/egg.  Although, at this point I get all of my protein from food.


Me too, love the grass fed ribeye. Since raising my fats a lot and dropping carbs WAY down - I max out protein and don't need the powder anymore. I didn't know soy had little effect on protein. Is this study from 2013 flawed?                                                            *The effects of soy and whey protein supplementation on acute hormonal reponses to resistance exercise in men*                                             "*CONCLUSION:*

Our main findings demonstrate that 14 days of supplementation with soy protein does appear to partially blunt serum testosterone. In addition, whey influences the response of cortisol following an acute bout of resistance exercise by blunting its increase during recovery. Protein supplementation alters the physiological responses to a commonly used exercise modality with some differences due to the type of protein utilized."                http://www.ncbi.nlm.nih.gov/pubmed/24015701


----------



## flood (Apr 20, 2014)

theCaptn' said:


> Collagen protein. Thank me later.


That's a great tip. Youtheory makes a collagen protein powder that would have saved me mixing collagen into my shakes separately. Neocell collagen 1&3 was $9 alone.


----------

