Everything about soy protein


There is hardly anything that affects the fitness community as much as choosing the right supplements. Whether it is the meaning and nonsense of exotic stimulants or basic macronutrients such as protein, the fronts between advocates and opponents of a product are often so hardened that it is rarely possible to think outside the box. Soy protein is one of those products that led to fierce trench fights within the scene and also in sports science that did not allow an objective consideration of the subject. In this article, we take a look beyond the box, highlight the pros and cons of soy protein and, last but not least, scrutinize some of the most persistent myths that have been captured in the collective memory of the fitness world to date.

What is soy protein?

In contrast to the classics of the dietary supplement segment, the soya protein is a vegetable protein derived from the soybean plant originating from East Asia, or the bean that produces it. Due to the original toxicity of the soybeans, the manufacturing process is very complicated, so that numerous steps in the context of special extraction and filtration processes are necessary to generate a ready-to-eat product that can be utilized by the human organism. Soy protein, in contrast to other plant proteins such as pea or rice protein, is characterized by the fact that it is a product with a complete amino acid spectrum. This implies that a soy preparation contains all nine essential amino acids that the human organism can not synthesize itself and, moreover, needs to synthesize key key proteins. Due to its short-chain molecular structure, the soya protein has a similar rapid absorption rate to whey protein and is therefore suitable as a herbal replacement for exercisers who want to do without animal products.

34.90 VAT included
36.00 26.90 VAT included
29.90 VAT included
*Neuer Geschmack*
24.90 VAT included
23.90 VAT included
*Neuer Geschmack*
27.90 VAT included
24.90 VAT included
*Neuer Geschmack*
24.90 VAT included

Which dosage forms of soy protein are there?

As in the case of the traditional protein preparations, the supplement industry also has a number of variants with regard to the soy proteins, which in some cases differ considerably in terms of their biological value as well as the protein, fat or carbohydrate content. On this basis, the soy flour represents the product group, which has 40-60 percent on the lowest protein content and is therefore hardly used in the form of shakes, but is particularly suitable as a protein-rich substitute for the production of baked goods. Soy protein concentrate is characterized by a protein content of 70-80 percent, but in return has a relatively high fat and carbohydrate content, which is why concentrate based soy protein powder are primarily used for cooking and baking. Due to the relatively low price, however, soy concentrates are also limited as a substitute for whey protein. A much higher-quality form of the soy protein is the so-called isolate, which is at least 90 percent protein content significantly higher quality than a simple concentrate. In addition, the isolate shines through better bioactivity, which in plain terms means that a much larger percentage of the protein can be utilized by the body. One of the most digestible forms of soy protein is the hydrolyzate, which is ideal for those who are struggling with digestive problems due to concentrate or isolate consumption. In the context of this manufacturing process, the protein structures are enzymatically broken down by the addition of digestive enzymes, so that they are available to the organism more quickly and do not cause unpleasant bloating. However, the cost of production is also significantly reflected in the price, so that both Kozentrat and isolate are the cheaper alternatives. 

Advantages and disadvantages of soy protein

In order for the human body to function optimally, it requires above all the nine essential amino acids phenylalanine, leucine, methionine, lysine, isoleucine, valine, threonine, tryptophan, histidine and cystine, from which it can produce numerous enzymes as well as non-essential amino acids. Since soy protein fulfills this criterion exactly, it is suitable as a multifunctional plant protein source, which moreover represents an adequate vegan substitute for whey protein due to its short-chain molecular structure and the associated short recovery time. In addition to the crucial role that soy protein plays in boosting protein biosynthesis, recent medical studies have found that soy protein consumption positively impacts many health factors. For example, a 2008 scientific study showed that consuming soy protein not only helps maintain muscle mass and slow down progressive muscle atrophy in old age, but also significantly reduces the risk of cardiovascular disease. Furthermore, an English study already in 1995 showed that soy protein can prevent the demineralization of the bone substance and thus the occurrence of osteoporosis. The biggest disadvantage of the soy protein, however, is the somewhat idiosyncratic taste of numerous soy protein preparations as well as the consistency of soy-made shakes, which in no way matches the creamy properties of a whey or casein shake.

Worth knowing about estrogens and lactose intolerance

Excessive consumption of soy protein, however, is more problematic from the health point of view as the soybean plant uses hormones to protect itself against predators. To the chagrin of the mostly male fitness athletes, these exact hormones are female sex hormones that are structurally very similar to estrogen and, accordingly, can lead to undesirable side effects. Consequently, the average daily soy protein consumption should not exceed 30 grams, according to the US Food and Drug Administration, so as not to disturb the body's own production of testosterone. Although studies have shown that the consumption of 50-60 grams per day is usually unproblematic, but to prevent the possible lowering of the testosterone levels, the official recommendation should be followed. In addition to vegetarians and vegans, those who benefit from the consumption of soy products include athletes who have pronounced lactose intolerance and thus can not tolerate even whey protein isolates, which have only a minimal amount of lactose. Thus, it is also possible for them to capitalize on the benefits of a rapidly absorbed protein preparation.


Soy Protein is a variable-use product that benefits athletes who want to avoid animal sources of protein while not compromising on the supply of essential amino acids. However, those who are not suffering from lactose intolerance or consciously abstaining from animal products should consider soy products rather as a temporary supplement or as an ingredient for baking and cooking, as a substitute for whey, casein or multi-component protein.