From being an exotic legume, known only to vegetarians, soybeans have become a prestigious food. Soy sprouts and soy milk are found in all supermarkets today and big brands continually present products that include it, from yogurts to cookies and breads.

But despite its popularity and the advertising that praises its properties remains little known and awakening some misgivings. Is it really an alternative protein source to meat? Aren’t your plant hormones dangerous? Is it true that it causes allergies?

The plant soybeans (Clycine max) It has its origin in the central regions of China, where its cultivation began about six thousand years ago and from where it spread to the rest of Asia. According to legend, Emperor Yan decreed in 2853 BC that it was one of the five sacred plants, with rice, wheat, rye and millet. Today it is still an important food in China, Japan and Korea.

In Asia, whole soybeans have always been consumed, in grain form, and products obtained from them in an artisanal way, such as tofu and fermented tempeh, natto and miso. On the other hand, in North America and Europe they drink milk, textured foods and protein concentrates.

Soybean properties

Soy is highly concentrated in macronutrients, minerals, vitamins and plant compounds beneficial to health.

quality protein

The biological quality of proteins is greater when the proportion in which the eight essential amino acids are found favors their assimilation. Egg white and milk protein have the highest biological quality, which is expressed with a rate of 1. The biological quality of soybeans is 0.91, almost equal to that of beef (0.92). Other legumes have a lower quality, such as chickpeas, with 0.78.

Soy is not only the legume richest in protein (37% of its dry weight) but these are also the ones that present the more balanced amino acid ratio, with an assimilation coefficient very similar to that of meat proteins and the advantage that they are not accompanied by saturated fats and cholesterol.

Vitamins and minerals

Folic acid stands out in soy (100 g of cooked beans provide 27% of what the body requires per day) and vitamins B1 and B2 (15% and 18%, respectively).

As for minerals, a serving of 100 g of cooked beans covers the 30% of the daily needs of iron, phosphorus and magnesium, as well as 13% of calcium. It also provides abundant manganese and copper.

Fiber and healthy energy

The richness in soluble and insoluble fibers helps regulate intestinal rhythm. Besides feeds beneficial microbiota and slows down the absorption of carbohydrates (100 g of cooked beans provide 173 calories), which makes it indicated for diabetes and weight loss diets.

Soybeans contain lecithin and phytosterols –the beneficial plant version of animal cholesterol–, which helps regulate LDL cholesterol and blood pressure and benefits the liver.

Benefits of soy

Everything indicates that, as it has been consumed in Asia for thousands of years, it is a healthy food that helps prevent diseases such as cancer, obesity, diabetes and cardiovascular disorders, and this is shown by epidemiological studies.

The disputed anticancer effect

The great virtue that is often highlighted in soy is its anti-cancer effect, due to the isoflavone activity such as genistein and diadzein.

These compounds, chemically similar to female hormones, prevent some types of cancer in various ways and are found in an amount of about 300 mg per 100 grams.

On the one hand, soy isoflavones increase the activity of the p53 protein, which inhibits or even kills cancer cells. They also block proteins, kinases, which slow the formation of tumors, and increase the activity of antioxidant body enzymes such as superoxide dismutase.

Finally, they act as «weak» female hormones that prevent access to the cellular receptors of the «strong» estrogens secreted by women, which in certain circumstances may be the cause of breast and uterine cancers.

However, some authors suggest that the hormonal effect represents a risk in people who are genetically predisposed or who have suffered from the disease. Therefore, some experts say that isoflavones prevent cancer and others that they can promote it.

Researcher Xiao Ou Shu, from Vanderbilt University (United States), in one of the most recent studies on the subject, carried out with 18,312 women with cancer, concluded that even they can benefit from isoflavones, since reduce the risk of mortality and recurrence. In any case, as there is not sufficient consensus, women with cancer, hereditary predisposition or doubts can consult with their doctor.

Friend in menopause

Soy is capable of reducing or eliminating the symptoms of menopause. The main proof of these properties is its lower incidence in Asian women.

However, some studies do not confirm the effect in Western women who take soy. Apparently, the cause of the difference is that a certain type of hair predominates among oriental women. intestinal flora which can convert isoflavones into active metabolites. This flora is also more common among vegetarians, as it is favored by a diet rich in fruits and vegetables.

It has been discovered that certain peptides (molecules composed of a few amino acids) peculiar to soy can inhibit the formation of adipose tissue. They also have antioxidant, anti-cancer, anti-inflammatory effects, lower cholesterol and blood sugar, and stimulate defenses.

All these effects are added to those of isoflavones in the same sense, since alsohelp control cholesterol and to properly distribute body fat, directing it to the hips and breasts, instead of the abdomen, where it is more dangerous.

Soy in the kitchen

To take advantage of the qualities of soy, you should consume between 2 and 8 servings a week, taking a glass of soy milk, 80 g of cooked beans or 100 g of tofu per serving.

Choosing organic soy is the only way to ensure that it is not genetically modified. In the United States, 94% of the soybean crop is soybean and in the world, 78%.

This extraordinary legume is very useful in the kitchen, especially if its derivatives are used, including tofu, tempeh, miso or textured soybeans.

The soy beans They can be prepared like any other legume, in a stew, a dish combined with cereals or a stew, as they are ideal for preparing consistent and old-fashioned dishes, that is, over low heat and without rushing.

Cooking dried soybeans takes a long time, as they must be soaked overnight and then boil for about three hours. You can also add a piece of kombu seaweed, which helps soften it and improves the flavor.

Green or unripe beans are another way to consume whole soybeans. They are known as edamame and cook in a few minutes. They are found fresh or frozen in oriental produce stores, they are ideal as a starter or aperitif and have a milder flavor.

Milk and tofu or tofu

Soy milk or drink, with a sweet flavor, can replace cow’s milk in cooking. Thanks to your lecithin content It is ideal for emulsifying sauces, such as «lactonesa», or preparing a light bechamel. You have to be careful with the heat, since it tends to cut if boiled excessively.

When cold, it allows you to make smoothies, ice creams and, in general, any dessert that is prepared with cow’s milk.

Tofu is prepared from milk and is known as tofu. Although it does not provide much flavor, its sponginess makes it easily absorb other aromas, and is used in both sweet and savory recipes.

Textured soybeans, also called textured vegetable protein, It is a good substitute for meat in cooking. It rehydrates quickly, looks like minced meat and absorbs the flavors well. It is ideal to add to pasta recipes, as a quick ingredient in eggplant and cannelloni fillings, or as a base for vegetarian burgers.

Tasty fermented

Fermented foods are where soybeans reach greater levels of sophistication.

The same is a real gem in the hands of an expert cook. There is a great variety of artisanal misos; The cheapest ones, industrially produced, do not have the same qualities.

It is used in small quantities and is an ideal condiment for any type of soup, cereal dish, legumes or seaweed. Mixed with vinegar, oil and some spices it can be used as a salad dressing.

He tamari or soy sauce is another product with a centuries-old tradition in Japan. It is obtained by fermenting soybeans with salt, water and sometimes toasted wheat, in the variety called shoyu. It is used as a dressing and in sautéed vegetables.

He tempeh, Originally from Indonesia, it is obtained by cooking whole soybeans and fermenting them with a fungus called Rhizopus oligosporus. It looks like a thin sponge cake with a mushroom flavor, and when fried it becomes meaty, which makes it suitable to replace meat in stews and casseroles.

He soy yogurt It is, finally, another popular fermented product, light and low in fat. It is delicious combined with fruits or in cereal salads, and is useful for giving creaminess to dishes.