Everything we need to know about soy in the diet
Soybeans originate in the northeastern regions of China. Once upon a time it was one of the 5 sacred plants (soy, rice, millet, wheat and barley). With the development of agriculture, soybeans were later used as an intermediate crop (because of the roots that bind atmospheric nitrogen). Soybeans are beginning to be used in cooking with the discovery of the fermentation process (tamari, soy sauce, meat). Soybean production and use in human nutrition is then expanding from China to Japan, Indonesia and the rest of the world. Soy is a legume that also contains some anti-nutrients (called Kunic triphin inhibitors) in addition to beneficial substances. One of them blocks the enzymes needed to break down proteins. Heat treatment does not completely break down these and other anti-nutrients and can produce serious stomach problems, reduce protein digestion and cause chronic amino acid deficiency. Soybean-fed animals were used in the experiments. Enlargement and pathogenic changes of the pancreas (including cancer) have been observed. Soy also contains hemagglutinin (a substance that causes blood to clot and increase blood pressure). Trypsin inhibitors and hemagglutinin have a strong calming effect. These two substances are neutralized during the fermentation process. However, some products (such as tofu) reduce the amount of these substances but do not completely eliminate them.
Soybeans are also rich in phytates, which block the absorption of essential mineral salts (calcium, magnesium, iron and zinc) in the intestines. Phytates are not eliminated by cooking, but their concentration decreases with a long and slow fermentation process. The effect of fermented soy products eaten with meat or fish is significantly reduced. The Japanese, for example, eat fish and tofu. Vegetarians who consume tofu (as a substitute for meat and fish) risk serious loss of these 4 minerals. The consequences of magnesium, calcium and iron deficiency are known, although the consequences of zinc deficiency are still insufficiently studied. Zinc is the so-called “element of intelligence” because it is necessary for the optimal development and work of the brain and nervous system. It has a role in protein synthesis and collagen formation. It has a role in regulating blood sugar and is important for a healthy reproductive system. Zinc is one of the components of many enzymes and has a role in the immune system. Phytates found in soy prevent the absorption of zinc much more intensely than other minerals.
Today, growing soybeans is a very lucrative business. For the past decades, soy has been promoted as a “healthy” food without cholesterol and rich in protein. Soybean products are often advertised as effective cholesterol-lowering foods. However, tests performed on humans have not confirmed these claims. Soy is also advertised as an effective food against cancer. An anticancer substance (a type of isoflavone) is indeed found in soybeans fermented in the classical way but not in products such as soy milk, tofu or boiled soybeans in which these substances are not present. Some researchers believe that the sudden increase in patients with liver and pancreatic cancers in Africa is a consequence of the introduction of soy into the diet of the population.
Fermented soy products contain proteins, vitamins, anti-cancer substances and important fatty acids, so they can be considered complete nutrients. However, soy products lack the amino acids necessary for the body. Therefore, it is wrong to consider soy products as a substitute for meat and milk. It has also not been scientifically proven that fermented soy products contain vitamin B12 (important for healthy blood and nervous system). Soy does not provide important fat-soluble vitamins (such as vitamin D) and retinol (vitamin A), which are catalysts for proper absorption and use of water-soluble minerals and vitamins. These water-soluble activators are found only in some foods of animal origin (meat, butter, eggs, fish and shellfish). Carotene of plant origin and sun exposure do not meet the body’s needs for vitamins A and D.
Only fermented soy products are safe provided they are produced from non-genetically modified soy and are consumed in certain foods (rice, seafood, meat and fermented vegetables). It should be borne in mind that milk, steak and soy dairy products can cause serious health problems (if they are constantly consumed as a substitute for meat). Experts say that soy was wrongly placed on the “pillar of shame” because the problematic proteins are thermolabile and no one eats raw grain. Today, there are soybean species that do not have these antimatters (inhibitors).