Soy vs Whey Protein – A Comparison

Browse through any online supplement store, or take a look at the shelves of a supplement store, and you will soon realize that when it comes to choosing a type of protein powder we really are spoiled for choice. There are literally thousands of different types of protein powder available for purchase, all of which boast a number of different benefits and claim that they are the perfect protein powder available on the market.

It is because there is so much choice, and so many bold claims, surrounding each different type of protein powder that determining which protein powder is the best is extremely difficult—especially if you’re a beginner to the world of protein supplements. Is soy or whey protein better?

Something that makes choosing a protein powder even more difficult than it should be is that companies selling protein powder will always manipulate research and state facts that portray their protein product in a positive light, even when this isn’t entirely true. The use of research in this way misleads customers, and makes the task of working out which protein powder is the best a near impossible task. However, it is far from an impossible task.

Two types of protein powder that people are always comparing with one another in order to figure out which one is best are whey protein and soy protein. The debate between which of these two proteins is better has been going on for years, due to a hotbed of conflicting opinions about each type of protein. This article plans to make a stop to this, by shedding some light on the soy versus whey protein debate, and coming to a final conclusion on which protein really is the better type. Read out to find out the results.

What Is Whey Protein?

Whey protein powder has long been considered to be the best type of protein supplement on the market, which is clearly shown by the fact that whey protein is the largest selling protein powder there is. It is a collection of globular proteins that have been isolated from whey, which is a liquid by-product of cheese manufactured from cow’s milk.

What Is Soy Protein?

Soy protein has always been the underdog when it comes to protein powder as other types of protein powder, such as whey, have always been considered to be superior. Soy protein is a plant based protein powder that is produced from soybeans. Like whey protein it is referred to as a complete protein as it contains all of the amino acids that the body requires.

So Which Type Is Best?

Now whey protein and soy protein will be compared with one another on a number of different aspects. Afterwards, a conclusion will be reached—hopefully ending the soy versus whey protein debate once and for all.

Their Impact On Testosterone Levels

One of the biggest reasons that people (especially bodybuilders, powerlifters and athletes) have been so against soy protein powder is because some studies have shown that it can cause a decrease in testosterone levels. This is thought to be because of the high level of phytoestrogens contained within soy protein, which increase the concentration of the female sex hormone estrogen, thus causing a reduction in testosterone levels. However, other studies have shown that this may not be the case, and soy protein may not cause a reduction in testosterone levels. However, there has never really been any debate over whether whey protein affects testosterone levels or not. Because of this whey protein has to be the winner on this aspect.

Their Biological Value

The biological value of a protein is a value that measures how well the body can absorb and utilize a protein. The higher the biological value of a protein is the better, and more high quality, the protein is considered to be. When soy protein is compared against whey protein in terms of biological value, the biological of whey protein comes out much higher. This means that whey protein is much easier for the body to absorb, meaning that it is much better for growth and repair. Again, whey protein comes out as the clear winner on this front.

Their Net Protein Utilization

Net protein utilization refers to the ratio of amino acids that are converted into proteins to the ratio of amino acids that were supplied. This is measured using a scale of 0-100, with a value of 100 meaning that all the amino acids supplied are taken up and used by the body. When compared with one another, the average whey protein comes out with a NPU value of around 92 whilst soya protein NPU value is usually somewhere in the low 60s. Therefore, in terms of NPU, whey protein is yet again the winner.

Their Levels Of Glutamine

Glutamine, although not recognized as an essential amino acid, is still extremely important for muscle growth and repair. Due to this, when looking for a protein powder, a lot of people look at what the glutamine content is before they make a decision. When soy and whey protein are compared with each other, soy protein tends to come out with the highest levels of glutamine. So for the first time in this post, soy protein is the winner!