Soy Protein: A Healthy Supplement Option?

Soy Protein: A Healthy Supplement Option?
Written by Michael Garrico

There is no denying the importance of protein in your diet. Every cell in the human body relies on this essential macro-nutrient, and your hair and nails are made almost entirely from it.

Not only is protein necessary for building and repairing tissue, it is needed for your body to be able to manufacture the enzymes, hormones and the chemicals that it needs to be healthy.

Protein is both essential for your body's basic functioning and enormously beneficial for good health.

Eating a diet high in protein ensures that your body receives many health benefits, including faster recovery after exercise, a quicker build up of lean muscle, less hunger throughout the day and an easier ability to maintain a healthy weight.

But how much is too much? Are some forms of protein better than others? In this article, we will seek the answers you are most curious about.

Does Your Diet Need More Protein?

Unlike other essential macro-nutrients like fat and carbohydrates, the body doesn't store unused protein, which means that you need to eat a constant supply to keep up your reserve levels.

Protein rich foods scheme

Meat, milk, fish, beans and eggs are all natural sources of protein, but oftentimes the body building enthusiast needs an extra boost to get the optimal amounts for their health and fitness

Because of this, many people rely on a protein supplement in order to maximize the amount of protein that goes in their body. Soy-based protein powders and shakes are an easy way to add extra protein into your diet to maintain your muscle growth.

However, many people have their doubts about relying on soy as a source of protein. Soy products have been blamed for a wide array of health problems, from increased estrogen levels to hair loss and even cancer.

Do these claims hold true through the hype? Are you better off leaving your soy based protein powder at home or can it be a healthy source of supplemental protein for your diet?

You don't need to be confused any longer. We've done the tricky work of looking through the contradicting health claims and are ready to share our results with you. By the end of this article you will know if soy protein is a smart supplement choice for you.

What Is Soy Protein?

Like other common forms of supplemental protein, soy protein has many positives and possible negatives for your health. The Soyfoods Association of America has defined soy protein isolates as the following:

Soy protein isolate can be found in a wide variety of health foods, ranging from protein bars, meal replacement shakes, bottled fruit drinks, meat substitutes and baked goods.

Soy protein isolate is a dry powder food ingredient that has been separated or isolated from the other components of the soybean, making it 90 to 95 percent protein and nearly carbohydrate and fat-free.

Soyfoods Association of America 

You can know that soy is an ingredient in your food if you see one of the following terms on the nutrition label: mono-diglyceride, soya, soja, yuba, TSF (textured soy flour), TSP (textured soy protein), TVP (textured vegetable protein) or MSG (monosodium glutamate).

Though not all textured vegetable protein comes from soy, a good amount of it does, while lecithin can be made from soy, eggs, or corn. To know for sure what is in your food, you can contact the manufacturer for a more detailed ingredients list.

Types Of Soy Protein

There are two main ways that soy protein is manufactured and sold: soy protein concentrate and protein isolate.

Soy beans

There are a lot of myths going around about soy protein, but some of them are also part-true...

Soy Protein Concentrate​

Soy protein concentrate is formed when the fat content is taken out of soy beans, leaving a white flaky substance in its place. After these flakes are given an ethanol extract to neutralize its pH levels, the substance is solid enough to be sold or used within prepared foods.

Because of the ethanol extraction, soy protein concentrate has a low level of isoflavine, (plant-derived estrogen) usually around 4% of the initial amount within the bean.

This makes soy protein concentrate a smart protein supplement for men that are worried about the side effects of consuming estrogen enhancers.

Soy Protein Isolate

After the formation of white flakes in soy, the concentrate is processed one more step through centrifugation that extracts the highest percentage of protein by weight.

The isoflavone levels remain higher (35-45%) than in soy protein concentrate because the step of ethanol extraction is skipped. Men that are concerned about estfrogen should avoid taking large amount of soy protein isolate.

Should You Be Eating Soy? Assessing the Health Effects

Answering whether soy is bad for you is a tricky question because it depends on many factors. How you consume soy products, the amount you eat, your age and gender and the way your body digests it all change the ways your body is affected by it.

In other words, there is no easy and accurate way to summarize how soy affects any individual body.

The Bad

In recent years, soy-based products have been getting a bad reputation. Many people believe that the majority of health claims for soy are actually false and the result of clever marketing schemes from food companies. Some of their worst claims to the contrary are as follows:

  • 90 to 95% of US-grown soybeans are genetically modified. This means that any soy product you buy is likely to be genetically engineered, and GMO foods have been occasionally found to pose health risks like hormone disruption and fertility problems.

In fact, Glyphosate, an active ingredient in the Roundup herbicide used on the vast majority of soy products, can disrupt estrogen levels and even wreak havoc within the female reproductive cycle.

Because Glyphosate is toxic to the placenta, it can damage or destroy it, occasionally resulting in a miscarriage or birth defects for children that are exposed.

Spraying with glyphosate on a farm

Herbicide called Glyphosate is toxic to the placenta.

  • Soy products can cause a lower sex drive. In some cases, eating excessive amounts of soy-based products can negatively effect your sex life

If you are a male and eat more than 25 grams of soy protein daily, the isoflavones that are present in soy products can reduce your testosterone levels, causing you to suffer from decreased libido or even erectile dysfunction.

  • Soy products can mess with your estrogen levels. Isoflavones from soy can activate your body's estrogen receptors and make your body act as if estrogen is present.

Because the structure of isoflavones is similar to estrogen, they can decrease you body's natural levels of estrogen, and mess with the menstrual cycle enough to reduce fertility in females.

The Good

You might be ready to swear off soy-based products for good after reading some of the purported negative health effects, but in truth the vast majority of soy products are not dangerous and are actually nutritionally beneficial instead.

Overall, soybeans have an impressive nutritional record. Each bean contains 30% carbohydrates (half of which are from fiber), 18% oil, 14% moisture, and a whopping 38% protein. Research into the benefits of soy protein have shown that they can help lower your LDL (bad) cholesterol levels by as much as 5%.

While that might not seem like much, small differences in your cholesterol level can have a big impact on your overall health.

Organic market drawing

Simply choose organic soy products on your market!

Simply choosing to consume organic soy-based products reduces your risk of being exposed to estrogen-damaging herbicides.

Likewise, here is a simple way to get rid of the negative hormone effects of soy and instead make it a safe and healthy food source: fermenting it.

The process of fermenting soy destroys the dangerous compounds it contains and makes it both safe and beneficial to eat.

Historically, Asian populations have eaten large amounts of fermented soy while being some of the healthiest and longest living people in the world.

Other evidence has shown that eating fermented soy can prevent osteoporosis, reduce your risk of various cancers, and prevent you from developing dementia.

Therefore, there is little to no risk for men and women to eat moderate amounts of soy protein isolate as part of a healthy, balanced diet. In this way, soy protein can be viewed as a one more nutritional tool to help you meet your daily protein needs.

When used like any other protein supplement, soy protein is a smart dietary choice.

Best Soy Protein Powders

There are dozens of soy protein powders on the market, but only a few stand out from the rest in regards to quality, good taste and nutrition. Below are three of the top soy-based protein products on the market and some crucial information about all three.


Produced by Maximum Human Performance (MHP) Probolic-SR is a soy protein mix that is formulated to release protein into your body slowly over time.

This keep you full longer while your body benefits from the precise muscle building proteins that will push your workouts to the next level and fill you with far greater anabolic and anti-catabolic benefits than other protein supplements.

If your goal is build muscle and keep yourself fueled longer, then Probolic-SR is a smart supplement to take.

Probolic SR, soy protein mix powder

Bobs Red Mill Soy Protein Powder

A step away from typical body-building protein mixes, Bobs Red Mill Soy Protein Powder prides itself on being a natural alternative to traditional protein supplements.

Bob's red mill soy protein powder

The protein powder mix is a nourishing source of protein that is completely dairy free, gluten free, unflavored and unsweetened.

You don't have to worry about consuming any artificial chemicals in your protein shake when you choose to add a scoop of Bob's Red Mill Protein Powder.

As an added benefit, every product from the company is certified Kosher and is millstone ground at slow speeds, ensuring that the nutrients and flavor of the grains is preserved, which means that you can know you are buying a high quality product.

Advanced Soy Protein

Created by Universal Nutrition, Advanced Soy Protein is a powerful protein supplement that can be used whether or not you are a serious athlete.

This supplement has all the essential amino acids that your body needs to convert protein into muscle, and the 100% water-washed process ensures you get the maximum benefits without any harmful additives.

By not exposing the soy product to the ethanol wash that is common with other soy protein supplements, your body gets the high levels of isoflavones that are found in soy beans naturally and consequently the maximum benefits from soy.

Whey Vs Soy: Which Is Better?

By far, the two most common protein supplements for body builders are whey and soy, and many people are confused about which one is best for them.

Because whey and soy have key differences in regards to content and nutritional value, it's important to understand these differences so that you can make the right choice for you.

The Health Effects Of Whey

As one of two protein components of dairy products, whey proteins come as a watery byproduct in the process of cheese production. (Casein is the other protein in milk). As an antibacterial compound, whey protein is useful for putting on body mass and maintaining bone health.

Goat wearing glasses

Whey and soy have key differences in regards to content and nutritional value.

For decades, whey protein has been considered the “gold standard” of protein supplement products and is the most popular type of protein among body builders.

Most nutritionists believe that the leucine found in whey protein helps to build up and repair muscles after an intense strength workout.

It's been assumed that whey has the ideal combination of muscle-building amino acids and that the body is able to utilize its benefits quicker than it can from other protein sources, making it a smart choice for a post-workout snack.

Side Effects Of Whey

Though whey protein provides you with a good balance of amino acids and minerals, there are concerns that it often contains toxic levels of nickel and copper. Also, because whey comes from dairy, anyone that is lactose intolerant will struggle to be able to digest it.

Some people are sensitive to the added ingredients in whey protein powders and suffer allergic reactions. Other negative side effects can include gas and bloating, cramps, headaches and general fatigue and exhaustion.

Soy Or Whey?

You probably won't be satisfied with this answer, but in truth, whether whey or soy is better for you depends largely on personal preference. Though whey has long been considered the ideal protein for body building, the truth is that the key benefits of soy are almost equivalent.

Soy vs whey sign

Moreover, soy is a great alternative protein source for anyone who is lactose intolerant or trying to cut down on their animal-based products.

Soy protein has been eaten by humans for over 5,000 years and is considered to be one of the highest quality plant-based proteins that nature provides. Each bean contains all the amino acids necessary for complete health.

The “feminizing” reputation of soy protein is largely unfounded, especially if you take the time to make sure your soy is sourced from high quality, organic sources.

In fact, recent studies have found that soy is just as effective (possibly even more so) than whey in its abilities to cause you to gain lean muscle mass.

For best body building results, why and soy protein should be used together.

Whey protein contains a large amount of branched chain amino acids, while soy protein has high levels of the amino acids arginine (a hormone that stimulates muscle formation) and glutamine (essential for workout recovery). Taken together, whey and soy protein supplements will keep you in peak physical condition.

Different Types Of Protein Supplements

You don't have to stress if neither whey or soy protein seems like the right protein supplement for you.

In fact, there are plenty of others on the market today that are filled with health benefits and will help you build up your muscles.

Below are some of the most common protein supplements available.

Egg protein powder is one option...

Egg Protein (Albumin)​

Egg protein powder comes from the whites of eggs and can be used in nutrition shakes and other foods where regular protein powders are used. Albumin can also be found in blood plasma, though for obvious reasons that isn't a recommended dietary source!

Hydrolyzed Protein (Liquid Aminos)

Some protein supplements can contain pre -digested protein, meaning that the protein has been broken down into its essential amino acids through a chemical process, making it easier to digest.

In most cases, the source of liquid aminos is soy, meaning that the final product will contain some monosodium glutamate (MSG) which occurs naturally during the hydrolysis process.

Pure Grown Amino Acids

Soy milk comic

More expensive than other types of protein, pure amino acids are made from fungi in a lab setting.

You can buy them in capsule form and they are considered useful for cancer patients that have a hard time absorbing other types of protein.

Some people can have an allergic reaction to them, so be mindful of this when trying them out.

Meal Replacements

Most health food stores will sell you meal replacement drinks, which are protein powders mixed with vitamins and minerals, often along with a sweetener.

Because they are nutritionally incomplete, meal replacements should be viewed more as a meal supplement than a replacement. Some people find them difficult to digest, so take the time to learn what types work best for your system.

Protein Bars

Despite advertising to the contrary, protein bars are often no more than glorified candy bars, filled with refined sugars and carbohydrates as much as protein.

Too much sugar is unhealthy, even when it comes from natural sources like honey or agave. Do your body a favor and keep your consumption of calorie laden protein bars to a minimum.

In Summary

Choosing the right protein supplement for your dietary needs can be tricky. However, soy protein is a great supplement choice for anyone that struggles to digest lactose and/or wants to avoid consuming animal products.

When organically sourced and eaten in moderation, soy protein is a smart choice for anyone aspiring to add extra protein to their diet.

Now we want to hear from you. What has your experience with soy protein been like? Are there any soy protein supplements that you would recommend? Be sure to let us know in the comments and we'll try to feature your suggestions in a later article.

About the author

Michael Garrico

I’m a 29-year-old personal fitness trainer and nutritionist living in sunny Miami, FL. I’ve spent the last 10 years staying at the forefront of the health and fitness industry.

In that time, I’ve helped hundreds of people shed the excess weight and get into shape, maintaining their healthy new lifestyle through proper training and eating habits.

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