Can you eat soybeans?

In this article, we will answer the question “Can you eat soybeans?” and discuss what happens when you eat raw soybeans?

Can you eat soybeans?

Yes, you can eat soybeans. Soybeans can be eaten in the form of a legume, such as the garbanzo bean and in the many other varieties of soy-based foods, such as tofu, edamame, natto, tempeh, soy milk and soy sprouts. Soybeans are one of the oldest food sources known to humans.

Who should eat soybeans?

People who are concerned about a balanced protein intake should eat soybeans, especially vegetarian. As a source of high quality protein, soybean is one of the very few plant-based foods to contain all of the essential amino acids, which make them a perfect substitute to meat. 

In addition, soybeans are indicated to menopausal women, as soybeans contain hormone-like phytoestrogens, which are naturally occurring compounds in plants. These molecules mimic the activity of the female hormone estrogen under the correct circumstances, having the protective effect in the menopause. Studies have shown that phytoestrogens can help prevent bone loss in aging women, can improve muscle and bone density quality and reduce body weight (6).

The regular ingestion of soybeans and soybean products are related to improved metabolic health in post-menopausal women, reducing the risks of obesity. This effect is due not only to the phytochemical of this rich legume, but also to its proteins. According to studies, soy proteins are associated with clinically significant weight loss, thus improving the levels of lipids in the blood (6).

Who should not eat soybeans?

People who are allergic to soybean proteins should not eat soybeans. In addition, people who have impaired digestion. 

Soybean protein is one of the 8 most common allergenic foods. Several potential soy protein allergens have been identified, including b-conglycinin, glycinin, soy vacuolar protein and the so-called Kunitz trypsin inhibitor (7). 

An impaired digestion is observed in young children and in elderly, which may lead to an incomplete protein digestion and protein remnants of the diet could act as allergens, increasing the allergenicity of the ingested food (8).

Soybeans are also not indicated to patients having achlorhydria, a disease characterized by low gastric acidity, and may be frequently found in older people (32.4% in subjects aged 74–80 years); in context with chronic alcohol consumption or chronic gastric infections. Characterizing this disease is a patient’s reduced disability to digest proteins, resulting in a resistance of protein rich food to gastrointestinal digestion. 

What does soybeans contain and how does it affect your health?

Soybeans contain about 40% protein, 23% carbohydrates, 20% oil, 5% mineral, 4% fiber and 8% moisture. 

Some health benefits of consuming soybeans are related to the many phytochemicals present in the plant, which may favor the cholesterol lowering, boosting of the immune system, preventing constipation and diabetes.

The biological nutraceutical compounds of soybeans have also been reported to provide protective effects against hormone-dependent cancers, cardiovascular disease, osteoporosis and menopausal problems (4).

Several nutritional intervention studies in animals and humans indicate that consumption of soy protein reduces body weight and fat mass in addition to lowering plasma cholesterol and triglycerides (7).

The favorable effects on weight loss can be explained, according to studies, by the increase in satiety offered by protein intake, which reduces appetite for long periods of time, among other factors.

How should you eat soybeans?

You should eat soybeans in the many forms of cooked, fermented or sprouted soybean products. You should not eat raw soybeans. Raw soybeans include a number of constituents that have the potential to create short-term negative digestive effects as well as long-term health concerns. 

Soybean products that are fermented are a good option, as fermentation reduces the antinutrients from soybeans. Fermentation increases the nutritional profile of foods, making them more digestible and flavorful. Some examples are natto and miso. 

Natto is made of fermented whole soybeans. It has a sticky, viscous coating with a cheesy texture. The basic process for making natto– is to wash, soak and steam the beans, allow them to cool to 60°C and mix in a starter of Bacillus natto– for an 8-hour fermentation process at 35°C.

Miso is a whitish-brown, brown or reddish-brown fermented soup-base paste. The basic process for making miso is to first wash the beans and soak and cook in water or steam. After cooling, the beans are mixed with salt and a koji starter (Aspergillus oryzae mould fungus) and allowed to ferment at 25–30°C for varying periods from 1 week to >2 years, depending on the final product requirements (4).

Why should you not eat raw soybeans?

Some anti-nutrients like phytates, saponins, trypsin inhibitor and lipoxygenase can be found in vegetable soybean. Some of the health risks associated with consuming raw soybeans may be mitigated via cooking or fermenting (3). 

Raw soybeans contain lectins and saponins that may produce nausea, gas, stomach discomfort, diarrhea, and vomiting in susceptible individuals. When consumed in sufficient quantities, this substance may cause weight loss, growth failure, and even death. 

Excessive consumption of soybeans are also related to the incidence of Lathyrism, which is a paralytic disease affecting the lower limbs. In lathyrism, the toxic substance interfaces with the formation of normal collagen fiber in the connective tissue (3).

What is Lectin?

Lectins, glycoproteins found in soybeans, attach to cells’ carbohydrates. Cell damage or death may occur in the gastrointestinal system as a result of this. lectins may attach to the intestinal walls, causing damage to the cells and reducing the absorption of nutrients (3). 

They can also cause short-term negative effects in the digestive system, such as nausea and diarrhea. Lectins, in contrast to other proteins, are not degraded in the gut by enzymes, therefore they are useless to the body. Lectins have the potential to disrupt the natural bacterial and immune system balance in the gut, causing damage that may allow infiltration of bacteria into the bloodstream (3). 

What are saponins?

Toxins in soybeans, such as saponins, may be harmful whether raw or cooked since cooking does not degrade them as lectins do, however, these toxins can be eliminated by soaking prior to cooking. When fermented, enzymes are utilized that may degrade saponins. Toxic saponins cause nausea and vomiting (3).

When consumed in high quantities, saponins, like lectin, may harm the intestinal cells. Raw soybeans are bitter because of the presence of saponins in the bean. Soybean saponins may be leached off by cooking processes, resulting in a sweeter bean. Saponins have a hypocholesterolemic effect in man (3).

What are protease inhibitors?

In raw soybeans, you’ll find proteins known as protease inhibitors, which prevent certain enzymes from working. If you consume raw soybeans, you may be blocking the pancreatic enzyme elastin, which breaks down meat proteins for digestion. 

Proteinases are used by the food industry to control viscosity, elasticity, cohesion, emulsification, foam stability and whip ability, flavor development, texture modification, nutritional quality, solubility, digestibility and extractability. Protease inhibitors are denatured through thermal processing, that is, cooking of the legume.

Other FAQs about Soybeans that you may be interested in.

Can you eat frozen edamame raw?

Can you eat soybean pods?

Can you eat raw soybeans?

Conclusion

In this article, we answered the question “Can you eat soybeans?” and we discussed what happens when you eat raw soybeans?

Reference

1. Djanta, Mahoussi Kadoukpe Arnaud, et al. Vegetable soybean, edamame: Research, production, utilization and analysis of its adoption in Sub-Saharan Africa. J Horticult Forest, 2020, 12, 1-12.
2. Palacios, Orsolya M., et al. Naturally occurring hormones in foods and potential health effects. Toxicol Res Applic, 2020, 4, 2397847320936281.
3. Bora, Parul. Anti-nutritional factors in foods and their effects. J Acad Indus Res, 2014, 3, 285-290.
4. Ali, Nawab. Soybean processing and utilization. The soybean: botany, production and uses. Wallingford UK: Cabi, 2010. 345-374.
5. Pieniaźek, Danuta, et al. Estimation of available methionine and cysteine in proteins of food products by in vivo and in vitro methods. Brit J Nutr, 1975, 34, 175-190.
6. Tang, Sijia, et al. Effects of soy foods in postmenopausal women: a focus on osteosarcopenia and obesity. J obes metab syndrome, 2020, 29, 180.
7. Velasquez, Manuel T., and Sam J. Bhathena. Role of dietary soy protein in obesity. Int j med sci, 2007, 4, 72.
8. Pali‐Schöll, I., and E. Jensen‐Jarolim. Anti‐acid medication as a risk factor for food allergy. Allergy, 2011, 66, 469-477.