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What is Soy Protein?
Soy protein is a type of protein that has been extracted from soy beans, typically in isolated form.
This type of protein is sourced entirely from plant material, making it an excellent choice of protein powder for many vegetarians and vegans around the world.
Soy protein is what is known as a complete protein, meaning that it provides a full spectrum of essential amino acids. This makes soy protein and arguably superior choice for vegetarians over foods such as rice, beans, nuts, and other incomplete protein sources.
Production of Soy Protein
Soy protein is sourced from milled soy beans which have been dehulled and defatted.
There will at this stage still be some small amount of fats and carbohydrates contained within the milled soy beans, so in order to create soy protein isolate the product is further refined and processed to create a product that is a minimum of 90% protein by dry measure.
Soy protein concentrate is also available, measuring in at around 70% protein by dry weight. This less refined product is generally found in items such as breakfast cereals, baby milk formula, and pet foods.
Concentrated soy protein is still a relatively high quality product but in the interest of achieving the very best results in our fitness and physique development efforts we are mainly concerned with the highly refined soy protein isolate.
What Types of Soy Proteins Are There?
The three main products derived from the manufacturing of soy protein are:
- Soy Protein Isolate (90% protein)
- Soy Protein Concentrate (70% protein)
- Soy Flour (50% protein)
Depending on the purity of these products they can be used in all manner of applications, including the manufacturing of gluten-free breads and baked goods, or the soy protein powders that we are more familiar with.
The products we will be discussing henceforth will almost entirely be manufactured using soy protein isolate.
Which Foods Contain Soy Protein?
As mentioned above, you can receive soy protein by eating, you guessed it, soy.
Soy can be used to create all manner of products, including
- Soybean Oil;
- Soy Sauce;
- Lecithin and Emulsifiers;
- Meat Substitutes; and
- Non-Dairy Milk and Cheese
All of these products will contain some amount of soy protein that if you really want to get the best overall protein content compared to fats and carbohydrates then you will definitely want to opt for a refined soya protein isolate powder.
Isn’t a Lot of Soy Genetically Modified?
We have already touched on the subject of the controversies surrounding soy, and GM crops are just another facet of this discussion.
There is no doubting the fact that much of the soy production around the world comes from genetically modified crops, so if this is something that you are averse to then you may want to look out for soy products which specifically use non-GMO ingredients.
There are a number of health food Manufacturers that specifically use organic, non-GMO ingredients to cater to those of you who would rather not take any chances in that respect.
It is worth considering that there are currently exists little evidence to suggest that genetically modified ingredients are necessarily harmful to our health or any worse than conventionally farmed crops.
Ultimately the decision lies with you, and will largely be dictated based on your personal needs, ethical alignment, and budget.
Which is Better, Soy Protein or Whey Protein?
It could be argued that whey protein is superior to soy protein because there are a number of beneficial hormones and growth factors contained within milk that you will not find in soy.
Variety really is the name of the game when it comes to constructing a sound long-term nutritional program, so with this in mind your best bet would be to rotate protein sources whilst ensuring you remain mainly reliant on whole food sources rather than supplements.
Combining a varied and balanced diet with a high-quality protein powder or two will be what really determines your long-term success as an athlete, bodybuilder, or health advocate; far more so than worrying about the minor differences between different types of protein powder!
Assessing the quality of Soy Protein Powder vs. Other sources
You can of course obtain some amount of protein by eating soy beans or products made with soy; however, as with any protein powder you will be able to enjoy a far higher per-gram protein content then you would from the unrefined product.
As an athlete of bodybuilder trying to obtain adequate amounts of protein from soy, you are going to struggle to achieve optimal results because you will also be consuming a considerable amount of fats and carbohydrates.
This will of course not be an issue with soy protein isolate powders because they are highly refined with a minimum of a 90% protein content.
Benefits of Soy Protein
Soy protein works in the same way as any other protein source in the sense that it provides our bodies with the essential amino acids that are needed for the growth and repair of cells and tissues.
The amino acids bound up in soy protein are used for a number of roles throughout the human body, covering everything from immune function to hormonal regulation, and of course the development of new lean muscle mass after an intense training session.
If you are looking to make consistent progress in your fitness endeavors then a basic protein powder is one of the most fundamental cornerstones of your supplemental regimen; if you also happen to be a vegan or vegetarian then a soy protein powder should make an excellent choice for you.
Not only does soy protein powder allow you to boost the protein content of your diet in an efficacious and healthy manner, it also makes it incredibly convenient as all you have to do is mix some powder and water in your shaker and you’re ready to go!
Who Can Benefit from Soy Protein?
Soy protein powders are typically marketed as health or sports supplements, which makes sense because athletes and bodybuilders will always benefit from ensuring an adequate intake of protein a daily basis.
You don’t need to be a vegetarian to benefit from using soy protein powder, and in fact it can be a good idea for long-term digestive health to rotate protein sources from time to time in order to avoid developing intolerances.
It is worth noting that some men are averse to the idea of using soy protein powders because of the potential for estrogenic effects; that is, soy’s ability to increase estrogen levels.
The research behind this is the next with the subject still being open to a lot of debate, so the best advice we can give in this context is to use your own due diligence and assess how your body responds to soy protein.
As for women, soy protein powders make an excellent choice whether you are a vegetarian or not, especially if you suffer from dairy allergies or lactose intolerance.
Does Soy Protein Have Any Side Effects?
Aside from the disagreement surrounding the subject of estrogenic production in men, there is also further controversy surrounding soy protein.
Soy-containing products are often marketed as being “heart healthy” or beneficial to cardiovascular health. Although soy consumption has been linked to a reduction in LDL or bad cholesterol, there is no evidence to suggest that this decrease is accompanied by an increase in HDL or good cholesterol.
This is a very complex area of medical science that is beyond the scope of this FAQ, but suffice to say there is certainly a lot of doubt around the subject of just how healthy soy protein is.
Soy protein definitely seems to hold a lot of promise, but until further studies have been conducted it is difficult to say with absolute certainty exactly what benefits you can hope to reap from soy in the long term.
As with any dietary supplement or manipulation, we recommend that women who are pregnant or breastfeeding consult their doctor or physician prior to use. This also applies to people under the age of 18 and individuals who suffer from pre-existing medical conditions or who are taking any kind of prescription medication.
Note: We recommend speaking to a doctor before taking any supplements.
How and When Should I Use Soy Protein?
Generally speaking, soy protein powders can be used in much the same way as any other whey, casein, or egg protein powder.
Ensure you are drinking plenty of water so that your body has what it needs to effectively process the additional protein, and always refer to the manufacturer’s guidelines on the packaging of any soy protein powder that you purchase.
How Much Soy Protein Should I use?
The amount of soy protein that you use is going to be entirely dependent on your personal needs, based on factors such as your body-weight, training goals, age, and the setup of your existing diet.
Again, refer to the usage guidelines on your soy protein powder for more information and you are sure not to go too far wrong.
1. Universal Nutrition Advanced Soy Protein
2. Bulksupplements Pure Soy Protein Isolate Powder
3. NOW Foods Soy Protein
4. Naturade 100% Soy Protein Booster
5. Nature’s Plus Spiru-Tein
6. Jarrow Formulas Iso-Rich Soy
7. Six Star Pro Nutrition Elite Series Soy Protein Powder
8. EAS Soy Protein Powder
9. Bob’s Red Mill Gluten Free Soy Protein Powder
10. MHP Probolic-SR