The Elite Physique

The Truth About Soy Protein

Here’s The Truth About Soy Protein

The truth about soy protein is an interesting topic.  Soy was all the rage some years ago in the media.  The government gave it a green light to the general public, suggesting it’s the 8th wonder of the world. The FDA recommend 25 grams of soy protein a day as a part of a diet low in saturated fat and low in cholesterol to help reduce the risk of heart disease.  With those suggestions, people flocked to this particular protein.

the truth about soy protein

Does Soy Protein Have Benefits?

Research began suggesting that soy protein may increase thyroid hormone while dieting and may enhance anabolic hormones levels for those weight training.  Interestingly enough, a great deal of real world and scientific evidence has recently come to light.  The truth about soy protein is that it is NOT that great for you, especially for male bodybuilders!

Soy is not just an inferior protein, it’s a bad protein because of the isoflavones that it contains. Two of these isoflavones;

  1. Genistein
  2. Daidzein

…are what cause most of the negative effects that comes with soy’s use.  Isoflavones are polyphenolic compounds that possess both estrogen-agonist and estrogen-antagonist properties. This classifies them as phytoestrogens — plant-derived compounds with estrogenic activity.

Soy Protein and Women

The two isoflavones, genistein and daidzein, bind to estrogen receptors as it’s home of choice, such as the Alpha and Beta receptors.  There isn’t a lot to worry about with the Beta receptors.  However, breast tumors, increased body fat, and water retention are associated with Alpha receptors.  It’s important to understand that genistein and daidzein bind to the Alpha receptor quickly and strongly.

If the compound that is bound to the site cause any growth, while stopping naturally-produced estrogen from binding, that would be the ideal situation.  However, the problem is that genistein does activate transcription (the process of constructing a messenger RNA molecule using a DNA molecule as a template with resulting transfer of genetic information to the messenger RNA) to a great degree once bound to the Alpha receptor.  This process will cause the growth of tissues.  If a tissue is cancerous, the cancer will grow.

What Does The American Journal of Clinical Nutrition Say?

The American Journal of Clinical Nutrition discovered substantial cell proliferation in breast tissue from soy products in 14 days.  In addition, BioMedicalCentral states, “In recent years the relationship between soy foods and breast cancer has become controversial because of concerns that soy-derived isoflavones, which exhibit estrogen-like properties under certain experimental conditions, may stimulate the growth of existing estrogen-sensitive breast tumors “

Now, if they didn’t activate transcription to a pronounced level, it would be considered an anti-estrogenic action and safe.  However, that’s not the case.  Also, women using performance enhancement drugs (PEDs) should stay away from soy.  

In 1992, the Swiss Health Service concluded that two cups of soy milk a day provides the estrogenic equivalent of one birth control pill.  In addition, infants fed soy formula gives the equivalent of five birth control pills.  Just keep this in the forefront of your mind; soy contains isoflavones that mimic estrogen in the body (phytoestrogen).  It binds to estrogen receptor sites and causes health issues.  Don’t take soy if you are pregnant and never use it as a milk replacement or used in infant formula.  Other soy side-effects for women are pre-mature puberty, hormonal disruption, infertility, and miscarriages.  Sadly, that’s the truth about soy protein. 

Soy Protein and Men

Research shows that soy protein decreases overall testosterone levels.  One study showed over a 75% decrease in testosterone production in men after taking in soy protein.  Another study, using healthy adult men on a diet consuming soy protein was compared to a diet of meat proteins revealed testosterone levels much lower on the soy diet.  In addition, genistein causes testicular cells to die in vitro studies.  With such definitive results, one should consider his or her protein choice.

It’s evident that soy protein lowers testosterone levels.  Since genistein binds to the same receptor site, you’d think that it would reduce estrogen activity some.  That’s not the case.  Genistein doesn’t stop the effects of estradiol.  It’s been shown to exert the effect when combined with estradiol.  So far, not a good outcome for soy.

Since soy lowers testosterone in men, and even increases estrogen, you can image the side-effects.  Men using soy products can see breast enlargement, decreased libido, moods swings, frequent depression, erectile dysfunction, and lowered sperm count.  In addition, research shows that it’s possible that soy’s isoflavones can cause growth and malignancy of the prostate.  This is due to the estrogen receptor Alpha is partly responsible for the induction of growth.

Soy and Muscle Growth

Soy is the vegetarian’s answer to a diet scarce in muscle-building amino acids.  It’s also pushed as a cholesterol-lowering supplement for “fattening” red meat.  We have all been brain-washed into thinking that animal protein and NATURAL saturated fats are bad.  We are also pressured into thinking that plant proteins, like soy, are here to save your muscle, your day, and your life.

There’s no such thing as soy protein and muscle growthSoy protein was beat by casein in breakdown and protein synthesis.  It can’t touch casein or whey.  Soy protein lowers protein synthesis and inhibited protein accretion, even on very low doses.   Soy protein has been shown to decrease muscular strength, lower testosterone, and increase cortisol when consumed post-training. The exact opposite of what we get from meat and dairy.  Sorry soy, you lose once again.

Marketing Soy As The Wonder Food

The government backed soy protein because it was believed that it reduced the risk of heart disease.  There’s more to that nugget of information.  Soy protein is clinically shown to decease HDL cholesterol, the GOOD KIND!

Much of the positive information we hear about soy is from companies and multi-level marketing companies marketing it, such as Herballife.  Shockingly, the soybean itself is toxic to humans as well as livestock because it is one of the most heavily sprayed crops.  Nearly 93% of it is genetically modified, which is very concerning.

A lot of companies will add soy protein to their protein bars and drinks.  Yes, it’s a little secret that supplement companies use.  It’s cheap and adds “protein” to the label.  Be cautious.  I’ve seen whey protein on the shelf in Walmart and on the back list of ingredients was soy protein.  This is why it is critically important to read every food and supplement label and make sure there isn’t any soy within the product!  If you really want at plant-based protein, try hemp, rice, pea, etc.

More Soy Horrors [Recent Studies]

The buck doesn’t stop there.  The truth about soy protein is that soy is responsible for a whole host of health problems. People seem to just pawn off their health issues on genetics when a lot of it has to do with their diet.  Soy isn’t as great as it’s marketed to be.

Did You Know That Soy…

  • Suppresses thyroid hormone
  • Causes GI upset
  • Alters brain function in a negative way
  • Is responsible for constipation, bloating, and nausea
  • Disrupts the endocrine system
  • Triggers allergic reactions (rash, itching, and in severe instances, anaphylaxis)
  • Increases potential for breast and prostate cancer
  • Inhibits reproductive health
  • Reduces appetite

To add to that, Linda Ray at states, “soy isoflavones can trigger food allergies in some people, with side-effects including itching, a runny nose, stomach irritations and digestive disorders. Doctors at the Mayo Clinic say soy supplements are in correlation with bloating, cramping and other stomach problems.”  But it’s not just allergies and digestive issues.  It can wreak havoc on your thyroid, your metabolic mastermind. 

The isoflavones, genistein and daidzein, have many harmful effects on thyroid production, testosterone production, muscle growth, and overall health.  A Japanese study at the Ishizuki Clinic shows that just 35mg of isoflavones a day can cause thyroid suppression in healthy individuals in just three months.  When your damage your thyroid, you will start packing on the body fat.  

But that’s not all.  The Journal of the American College of Nutrition shows cognitive dysfunction and brain atrophy in men taking in two or more servings of tofu a week.

Oh, But We Use Soy Protein Isolate!

So, what is the difference between soy protein isolate (SPI) and concentrate?  Isolate undergoes more processing, which results in a higher protein content with less carbs, lactose and fat. The main difference between the two (isolate and concentrate) is that isolate is the purest form of protein. Isolate usually contains between 90-94% protein while concentrate has a protein ratio of around 70-85%.  Soy protein isolate also contains phytates, which can decrease mineral absorption.

Soy protein isolate is soy’s heavily processed stepchild, an inferior protein. It’s a protein that does more damage than good. Soy protein isolate or concentrate, they are both a poor choice. If you want a high-quality protein, one that will do your body and health good, choose whey protein.

Whey is the dominant protein in mother’s milk and has a biological value (BV) of 104-159, depending on purity, the highest of all protein sources.  BV is a measure of a protein’s ability to be used by the body, simply meaning that it yields more usable grams of amino acids so it is easy to absorb.  Soy’s BV is 73, very low on the totem pole.   In addition, whey also contains the highest amount of BCAAs.   That’s a two-for-one-shot!

Herbal Life Cult Soy Protein

I’ve been having my The Elite Physique business since the mid 1990s. I started in Baton Rouge, personal training at many of the gyms in the greater Baton Rouge area. I moved to speck on the map, Miami, OK in 2002. There’s no opportunity here, so I stated this website to write and sell my eBooks as well as online personal training. After 18 years online, with 15 eBooks under my belt, and thousands of clients online, from the MAC girl to an American Gladiator as clients, I get this email from a woman in this small town. Keep in mind that she’s an herbal life distributor. She unsubscribed from my Bodybuilding Course online.  Here’s her reason…
I know Karen personally from the gym. This website looks like a Tv infomercial full of scams.

She sells herbal life. She’s CAUSING health issues and she has the nerve to talk smack to me, after I’ve been in the fitness industry for over 30 years.

Here’s my response:
Wow. This is Karen. The entire website is mine (both and

It’s FAR from a scam. EVERY word on both my websites were written by me and all my eBooks are written by me. I created these sites so women could have a bodybuilding information source. I’ve been having these websites for 18 years now and I’ve never been called a scam.

Lesson 1, you didn’t even opened, so how do you really know my information level? Might read it and let me know what’s so scammy about it. I give SOLID information and a before/after photo testimonial… From a REAL client.

Sorry, but I hate being called something I’m not… even after 32 years in the sport.

In addition, I spent thousands of dollars on how to build and run a successful website the right way. For you to sit there and tell me that the business that I built is a scam is a personal jab. I’ve been in bodybuilding for over 30 years. It’s who I am. And apparently you see me as a scam artist. I THOUGHT women were to help empower one another.

But if you want to compare apples, you need to take a look at your  herbal life. The staple ingredient is SOY! Soy is the WORSE kind of protein you can put into your body. The BV is below that of car oil. Soy causes cancer and leads to man boobs in men.

And this is why I hate “Miami, OK”.  People don’t know what they don’t know. You spend your entire life in something, building and creating the best it can be, and someone, anyone who knows nothing can came along and yell scam.  You don’t know me personally… You just know who I am.  Oh, and I DID do an infomercial for the NuWave Oven, but that’s NOT on my websites.

Karen Sessions NSCA-CPT

What About Fermented Soy?

Soy protein is actually an anti-nutrient.  This means is has certain enzyme blockers that block the absorption of minerals and proteins.  For example, Phytic acid is a distinctive natural ingredient located in plant seeds. It’s been in the limelight due to its effects on mineral absorption. Phytic acid blocks the absorption of minerals such as iron, calcium, magnesium, and especially zinc.  This leads to mineral deficiencies.  Unless that soy is fermented, you are going to have a lot of problems.

So, we established that soy is an inferior protein for many reasons.  But, can you have fermented soy?  Yes, in limited amounts.  Things such as miso, natto, tempeh, touf, etc. are acceptable in limited amounts.  It has to be fermented soy, either organic or non-GMO.  Those are the only options.  But remember, keep it in moderation.

Final Soy Thoughts

The bottom line, recent studies prove that soy sucks.  Soy protein costs just PENNIES to make and they charge you a pretty penny for it.  In the end, you get the short end of the sick, twice.  If you want a quality protein, one that is actually going to do your body, health, and muscles good, invest in a high-quality whey protein.  In addition, eat real meat such as chicken, turkey, steak, fish, etc.  

Now, check out my free guide below on how to build impressive muscle quickly, easily, and naturally…


Build Impressive Muscle Using Natural Tactics

Now that you have a bit of information of what NOT to consume, try the recommendations in my FREE Guide.  This is what you need to take your physique to the next level.

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Karen Sessions NSCA-CPT

Build Impressive Muscle Using Natural Tactics

My name is Karen Sessions and I am a life-time natural female bodybuilder, multi-certified fitness instructor, author, specialist in performance nutrition, and a success coach. I've been in the fitness industry since 1988! I teach people Just Like You how to transform their bodies, get in shape, build muscle, lose fat and compete in Bodybuilding, Physique, and Figure Competitions. When you have the CORRECT information you can have total confidence and turn your dreams into reality... and I can help transform YOUR body. I have helped THOUSANDS of clients reach their goals and I can help you, too. Be sure to grab my free gift above so you can start moving toward your goal.

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