Which is better, soy protein or whey protein?

Abstract: There are many different types of protein powder on the market, and each type also has different effects. Many people often ask, what is the difference between different protein powders? So today we will talk about the difference between the two most common protein powders-whey protein concentrate and soy protein isolate?

Keywords: soy protein, whey protein

Related products for this article: soy protein


Soy vs. Whey: A Comparison

Whey protein, concentrated from milk amino acids, receives high praise from sports and nutrition circles. Soybeans, also known as edamame, are among the highest-protein plant crops. Soy protein is extracted from these beans.

Whey protein has long been the star of resistance training supplements. Most people default to whey when mentioning protein powder. However, recently, soy protein has gained popularity, especially among women. It is a plant-based protein and a whole herb extract. So, which protein powder is better for fitness and nutrition?

Protein: Who is Stronger?

First, let’s compare the protein content of both. The Kjeldahl method shows whey protein’s conversion factor is 6.38, while soy protein isolate’s is 5.71. This method calculates protein content from nitrogen content.

However, we must also consider amino acid ratios. Modern nutrition stresses balanced amino acids. Scholars studied the composition and essential amino acid ratios of both proteins. They found whey protein superior in both protein content and amino acid ratio.

Whey Protein: Better Muscle Growth

Different protein powders affect hormones differently. Scientists compared hormonal changes from 12 weeks of resistance training with whey or soy protein. The testosterone-to-estrogen ratio was higher in the whey group, linked to enzyme activity. For muscle gain and fat loss, whey protein seems more effective.

Higher testosterone and lower estrogen levels in the whey group promote muscle growth and reduce fat. Whey protein also enters muscle tissue faster, making it a more efficient post-training supplement.

Whey Protein: More Conducive to Fat Loss

Calorically, whey and soy proteins are similar. However, some whey brands have fewer calories. This means consuming the same protein amount with fewer calories.

Additionally, whey protein benefits fat loss. It contains branched-chain amino acids (BCAAs). Consuming BCAAs before and after exercise helps the body burn fat without losing muscle.

Overall, whey protein is more suitable for muscle gain and fat reduction after resistance training compared to soy protein.