Soy – Healthy Or Unhealthy? The Fact Check

The vegetarian and vegan diet is becoming increasingly popular. With the growing demand for plant-based foods, the supply of meat substitutes on the market is also increasing. This is precisely where soy plays a vital role and forms the basis of these alternatives. However, negative headlines keep popping up about the harmful effects of soy on the body. Phytochemicals in soybeans are said to reduce male fertility and even promote the development of cancer. 

What Is Soy Anyway?

When we talk about soy, we mean soybeans. They belong to the legume family and are an integral part of the diet, especially in Asia. Soybeans are mainly processed into tofu, soy sauce, or milk and yogurt alternatives. Meat substitutes often play an essential role, especially in connection with a plant-based diet. Soy alternatives such as tofu sausages or veggie Bolognese can now be found in almost every supermarket. The popular starter consists of unripe harvested soybeans topped with a little coarse salt.

Is Soy Unhealthy?

We can reassure anyone who asks whether soy is unhealthy and say clearly: soy is healthy!  Natural soy products are not only convinced with their very high protein and nutrient content but are also characterized by their low fat and cholesterol content. Soy has a high biological value, which means that it can be used very well in the body. 

Soy protein contains 7 of the eight essential amino acids and has an almost complete amino acid profile. Protein building blocks are called essential amino acids and have to be taken in with food, as the body cannot produce them. Soy is ideal as a high-quality source of protein in a vegetarian or vegan diet. 

Why Should You Eat Soy?

  1. Very high protein content (with 34% of the front runners among all legumes)
  2. It contains polyunsaturated fatty acids 
  3. High fiber content
  4. Provides essential minerals and trace elements (calcium, magnesium & iron)

Nutritional Values ​​Of The Soybean

Average Nutritional Values ​​Per 100 G

Calories                    323 kcal

protein                     34 g

fat                           18 g

carbohydrates            6 g

Fiber                        22 g


Soy Rumors – Myth Or Fact?

Soy products are repeatedly criticized for a variety of reasons. Let’s take a closer look at the myths surrounding soy. What is really behind the rumors – is soy unhealthy and harmful to health? We clarify!

Soy Is Unhealthy And Increases The Risk Of Cancer

The study situation on soy is not yet uniform, but positive effects on health have been found in Asian countries. People who regularly eat natural soy products have a lower risk of breast and prostate cancer and cardiovascular disease. Only people with thyroid problems should ensure that they have sufficient iodine intake, as soy consumption can inhibit iodine absorption in the body. Otherwise, the soybean is said to have health-promoting properties due to its valuable nutrients.

Soy Reduces Fertility

The soybean contains secondary plant substances, so-called isoflavones. These belong to the group of phytoestrogens and are related to the female sex hormone estrogen. But don’t panic: the effects in the body are different, so soy has no adverse effects on testosterone levels in men. On the contrary: some studies prove a positive effect on fertility!

Soy Consumption Is Destroying Rainforests

The rumor that valuable rainforest is being destroyed for soy cultivation is true. However, the increased consumption of soy in a plant-based diet must not be blamed here. Because 80% of the grown soy is used for animal feed in factory farming, and only a tiny part is used for direct human nutrition. Soy products such as tofu or milk alternatives are therefore not the leading cause of the destruction of the rainforest.

Anti-Nutritional Ingredients

Like many other legumes, raw soybeans also contain so-called protease inhibitors, inhibiting the protein-splitting digestive enzymes. However, these can be inactivated by heating, pasteurization, fermentation, or germination and are therefore no longer contained in products such as soy milk and tofu. Because of this, all soy foods are heated in production, and anti-nutritional ingredients no longer play a relevant role in the end product.

Phytic Acid Under Fire

Isoflavones belong to the group of phytoestrogens. Although these are found in many plants, the content in soy is noticeably high. Phytic acid is responsible for the reduced bioavailability of essential minerals. It can be insoluble to bind zinc, iron, calcium, and magnesium ingested with food. 

As a result, these minerals can no longer be absorbed by the body. However, the phytic acid concentration in soy foods is still relatively low due to the manufacturing process. The fermentation reduces the phytate and thereby improves the bioavailability of minerals. The phytic acid in soy foods does not affect the calcium and iron balance in a balanced diet.

A Slight Digression: Vitamin B12

In an omnivorous diet, the supply of vitamin B12 is ensured through animal products. However, this vitamin is not found in plant-based foods. Therefore, especially in the vegan diet, you should pay attention to a supplement of vitamin B12 to prevent a deficiency.

How Much Soy Is Still Healthy?

The consumption of normal quantities is utterly harmless according to the current state of scientific knowledge. In general, there is no large specialist society in the world that advises against soy consumption. 25 g of soy protein per day as an upper guideline value. This corresponds to an amount of approx —300 g tofu or 800 ml soy milk. 

But do not worry: you will typically not reach these intake quantities with a balanced and varied diet. You don’t want to worry about nutrients in your everyday life but rather enjoy eating? Our nutrition plans are optimally tailored to you and your needs.

Childhood Soy Consumption

Soy products should not be substituted for dairy products in infant nutrition. In around half of all children, a soy allergy disappears by school age. 70% of affected children have developed soy tolerance by the age of ten. Nothing speaks against the occasional consumption of soy products as part of a balanced diet in childhood. It is only pointed out that soy products used as milk substitutes should be fortified with calcium to ensure an adequate supply. There is, however, a need for further research in this area. 


Soy is versatile and impresses with its good taste and valuable ingredients. The legume not only serves as a source of protein but also provides a lot of essential nutrients. Soy products such as tofu or tempeh can make a necessary contribution to a balanced and healthy diet. Of course, you can also eat soy-free, but there is no reason to remove soy from your diet from a nutritional point of view. Not sure how to prepare your tofu yet? You will find a variety of delicious vegan recipes in our free database.


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