Soybeans for More Than Just Quality Protein
Protein is an important source of heat and energy for the body, and animal proteins are considered better in quality than plant proteins. However, animal proteins have many other substances that are considered harmful to health, such as fat and cholesterol, particularly when consumed in large quantities. Thus, we face a dilemma: we want high-quality proteins, but we do not want the undesirable substances found in meats.
Soybeans can resolve this dilemma. Soybeans have been grown in China for more than 3,000 years, and they were first exported to Europe in the eighteenth century. In 1960, when China was experiencing a severe economic recession with a critical food shortage, an increasing number of Chinese people were suffering from edema (a condition in which the body tissues retain an excessive amount of fluids). The Chinese government began to supply people with soybeans in great quantities, which rapidly brought this widespread disease under control. How did the Chinese know about using soybeans to relieve edema? The medicinal uses of soybeans in China date back to the third century B.C., when the first Chinese book of medicinal herbs, entitled Agriculture Minister's Collection of Medicinal Herbs, was published. This classic lists 365 medicinal herbs, including soybean, clearly demonstrating the Chinese belief that soybeans are very important to health, whether used as a food or an herb.
In a subsequent book of medicinal herbs, entitled Records of Celebrated Physicians, published towards the end of the Han Dynasty (206 B.C.-A.D. 220), it says: "Soybeans can dispel retention of excessive tissue fluids." This statement by a professional herbalist marked the beginning of soybeans as a remedy for edema. Later, the greatest herbalist in Chinese history named Shi-Chen Li (1518-1593) published his celebrated work in 1578, entitled An Outline of Materia Medica, where he recommended soybeans as an effective remedy for "kidney diseases, water retention, and poisoning."
As we have seen, the Chinese not only regard soybeans as food but also as an herb capable of healing many diseases. In addition to curing edema, they found soybeans to be helpful in treating the common cold, skin diseases, beriberi, diarrhea, toxemia of pregnancy (various symptoms during pregnancy, such as vomiting, acute yellow atrophy of the liver, and renal failure), habitual constipation, iron-deficiency anemia, and leg ulcers. Small wonder that there is such a wide range of soybean products--from bean curd (or tofu) and soybean sprouts to flour, dried bean curd, and bean drink--all of which are considered very beneficial to health.
Another important use of soybeans is to promote lactation. Chinese farmers know how to increase cow's milk secretion by feeding them soybean milk. And in old China, when life was very difficult, a nursing mother knew how to fry soybeans until they were aromatic and then steam them with turnips and fresh ginger to eat at meals for promoting milk secretion. In the twentieth century, we know that during the period of lactation, the mother needs additional calcium to offset her loss of milk. But we must remember that the use of soybeans in a diet to increase milk secretion in nursing mothers dates back over 1,000 years when no scientist in the West knew about calcium or any other nutrients. Soybeans are indeed a calcium-rich food as the Chinese have discovered in modern times, and this shows that the ancient Chinese practice is consistent with that principle of modern nutrition but at least 10 centuries ahead of it.
In Japan, Dr. Y. Toyora has pointed out that most of the Japanese athletes who have won gold medals at Olympic Games have taken soybean proteins as their main source of heat and energy. He also noted that Chinese workers have demonstrated higher levels of energy and endurance than others, which may be attributed to their regular consumption of soybeans and soybean products. But is there any indication that soybeans directly contribute to longevity? Japanese researchers conducted an experiment in which animal proteins were used to feed one group of lab animals while plant proteins were used to feed another group. The results of the experiment show that the first group grew faster but with a shorter life and the second group grew more slowly but lived longer. And in his book, Longevity and Eating Habits, Professor Kondo Shoji of Tohoku University in Japan has pointed out that according to his research, the geographical regions in which soybeans are produced seem to have a higher percentage of longevous people.