Soy: The Versatile Plant Source Of Protein 

Soy protein (foods) derived from soybean are more popular than ever, with the US emerging as the second highest soy consumer globally after China. The primary reason for soy’s overwhelming popularity is its high protein content. Once a niche product among individuals on a meatless diet, soy is also gaining prominence among animal protein consumers. 

Although some online publications question whether soy protein is safe to consume, the plant-based protein source has numerous benefits transcending its protein content. Therefore, below is an overview of soybean, its benefits, and the U.S. Soy products available on the American consumer market. 

The History Of Soybean In The US 

Soybean consumption is several millennia old, with one historical account tracing its domestication to 1100 BC in Southeast Asia, particularly China. However, soy consumption in the US is much more recent, as the first mention of the legume in North America was in the 1860s. The soybean made its way to Britain and the rest of Europe in the early 1700s before the British colonialists introduced it to the present-day USA south. 

The legume’s primary use immediately after its introduction to US soil was as a fodder crop in animal rearing. However, the United States Department of Agriculture began conducting on soybeans in the late 1800s and early 1900s and identified the legume as a potential edible oil and protein source. 

Moreover, besides its potential nutrient benefits, researchers also discovered that the soybean plant facilitated nitrogen fixation. Therefore, they encouraged American farmers in the hot and humid regions where soy plants thrived by rotating the soybean plant with other plants, including cotton, to keep the soil fertile. Moreover, American farmers formed the American Soybean Association in 1919 and grew over 10000 soybean varieties by the early 1930s. 

While the soybean was popular as animal feed, its popularity as a human plant-based protein source in the US grew in the 1960s, following research that linked the legume with heart health. Moreover, the US Food and Drug Administration (FDA) recommended taking 25mg of soy daily to reduce the risk of coronary heart disease.  

Fast-forward to 2022; the US is the world’s second-largest soybean producer and consumer thanks to its nutritional profile for humans and animals and its industrial applications. Soy protein has multiple industrial applications, including producing plastics, dyes, rubbers, lubricants, adhesives, fibers, and coatings. 

Soy Nutritional Profile 

Soy Protein 

As stated earlier, soy’s popularity in the US market arises primarily from its nutritional profile as a high-quality protein source. According to one research study, raw soybean contains 40% crude protein and 20% fat.  

Moreover, unlike most plant-based protein sources, soy is a complete protein. Complete proteins contain all nine essential amino acids in quantities that meet human nutritional needs.  

The human body cannot synthesize essential amino acids; hence you must acquire these amino acids via diet. Most complete proteins are animal sources like meat and dairy, although a few exceptions, like the soybean, exist.  

Other Soy Nutrients 

Soy has an outstanding nutrient density, and its exceptional protein content is one of its many nutritional benefits. Nutrient density is a nutrient profiling system that classifies foods based on the macronutrient content weighed against the calorie intake.  

Foods with low nutrient density are air calories, meaning you must eat large portions to reap any nutrients from such foods. However, macronutrient-dense foods like soy deliver maximum nutrients per serving, allowing you to control your calorie intake. Below is an overview of other macronutrients in soy besides soy protein. 

Polyunsaturated fats 

As earlier stated, raw soybean contains 20% fat. However, while most health-conscious individuals shy away from fats, soy contains healthy fats called polyunsaturated fats.  

Polyunsaturated fats (PUFAs) are crucial for healthy human body cell generation and maintenance. Moreover, they are crucial for nerve function and brain health, helping prevent mental decline, among other systemic body function benefits. Omega-3 fatty acids are the dominant PUFAs in soy. 

Fiber 

Soy contains a high content of soluble and insoluble fiber.  According to one study, soy fiber has multiple benefits, including improved laxation and lower cholesterol.  

Vitamins 

The soybean has a vitamin concentration, especially B complex vitamins, including folate (vitamin B9), pyridoxine (vitamin B6), niacin (vitamin B3), and Thiamin (B1). Moreover, the legume contains vitamins E, K1, and C. 

Minerals 

Besides vitamins, the other macronutrients present in soy are minerals. The legume has a high mineral content featuring iron, magnesium, manganese, phosphorus, potassium, zinc, and copper. 

Soy Therapeutic Benefits 

Soy’s macronutrient density improves the body’s function and health. However, soy is a superfood, and superfoods have health benefits beyond their nutrient value.  

Besides macronutrients, soy contains phytochemicals, or compounds called isoflavones, that interact with the body’s receptors to induce therapeutic benefits. Below is an overview of soy’s health benefits. 

Breast Cancer Risk Reduction 

The isoflavones in soy have an estrogen-like effect, albeit milder than endogenous estrogen. Estrogen is the primary female sex hormone, and high levels may contribute to breast cancer cell and tumor growth.  

However, one study shows that the isoflavones in soy bind to estrogen receptors and can cause either estrogenic or anti-estrogenic effects, depending on the endogenous hormone’s levels. The study posits that soy’s anti-estrogenic effect likely reduces cancer risk.  

Moreover, one observational study showed that Asian women who consume soy regularly have a 30% reduced breast cancer risk. The study also established that women who consume soy while diagnosed with breast cancer have a lower recurrence risk.  

Prostate Cancer Risk Reduction 

Besides breast cancer, soy also benefits prostate cancer risk reduction. One study concluded that isoflavone and other soy phytochemicals work synergistically to induce cytotoxicity (cell death) in cancerous prostate cells.  

Low Cholesterol 

As stated earlier, the PUFAs and fiber content in soy helps lower blood low-density lipoprotein (LDL) or bad cholesterol levels.  

Bone Health 

According to one study, dietary soy increases or sustains bone formation by maintaining the balance between natural bone density formation and degradation.  

Soy Foods 

The soy consumer market features multiple soy foods to satisfy nutritional and therapeutic benefits. You can choose between whole soy foods like edamame, Tempeh, Tofu, and Miso or highly-processed products like soy protein isolate.  

Moreover, modern soy foods like soy milk, yogurt, cheese, and textured soy meat substitutes are available. You can use soy products to prepare various dishes, including curried tofu, meatballs, soy flour tacos, and more. Soy has a mild flavor that absorbs flavors from other ingredients.  

Conclusion

Soy is a highly versatile plant protein with a high macronutrient density, therapeutic benefits, and industrial applications. Moreover, diverse soy foods also allow food prep and recipe recreation diversity. However, like any good thing, consume soy protein in moderation for maximum health benefits.