5 reasons why we never use soya protein

Reflex Nutrition - Feb.05.19

 Here at Reflex Nutrition we've been proudly claiming that we never have and never will use soya protein as a protein source for 25 years. 

We wanted to expand on why we don’t choose to use soya protein. We hope that this will encourage you to ask the question "what's in my shake?" And, think twice about taking a protein shake made primarily from soya protein. 

Here’s why we never use soya protein and choose high-quality whey from grass-fed cows or pea protein as a vegan alternative

1. Soya Protein is less beneficial for gaining strength

One study looked to determine whether increased soya protein intake combined with resistance training enhanced strength gains in older adults. They concluded that increased soy protein intake actually reduced gains in muscle strength compared with increased intake of dairy protein or usual protein intake. Not an ideal protein supplement if you’re looking to build your strength and put on muscle!


2. There are health concerns with how soya protein is manufactured

Soya protein is largely derived from GMO soya crops, which are used to make soya protein isolate. One of the cheaper and commonly used extraction method to make soya protein is a solvent called hexane. Several studies have revealed that hexane affects the nervous system when inhaled. Certainly not something you’d want from your protein shake!

The question is how can you tell if the soya protein in your protein powder contains traces of hexane? You can’t, without going to the effort of questioning the supplement company. It is not something you’d find on the label so instead we suggest just avoiding soya protein all together.

(Source one, source two, source three

protein label

3. Soya protein is a cheaper alternative to whey or pea

We can understand why some supplement companies choose to use soya protein – it is a cheaper source, meaning more money for them. However, we truly believe that quality in is quality out. Why put the cheapest thing in your body when you can opt for the best?

the best protein

4. Soya protein is less efficient in the body than whey or pea

As soya protein is a cheaper alternative, it is often not processed to a sufficient degree to make it as efficient as possible.

Soya protein has also been shown to obstruct the amount and rate of protein absorption in the body, making it less efficient for muscle growth, when compared to whey or pea.


weight lifting

5. Soya protein has less amino acids than whey or pea

Amino acids are the building blocks of protein, which will help you to maintain and grow your muscles. Soya protein and whey protein both contain the nine essential amino acids and are complete proteins but it’s all about levels and soy protein isn’t quite up to scratch!

Soya protein has higher levels of arginine, phenylalanine, and tryptophan; Whereas whey protein has higher levels of leucine, isoleucine, methionine, and lysine. Science has shown there is association between lysine and muscle growth. As whey is considered to have a better base of amino acids it’s the obvious choice!

 protein tub

We hope that goes some way to explain why we have, and why we always will say no to soya protein.

Not sure what whey or pea protein to opt for? We can help with that too! Here's a guide to the different protein sources.

Please note, this blog is not in any way an allergenic claim. For allergen information, please refer to individual product ingredients lists.