Soybean Oil: Nutritional Facts and Health Benefits

Soybean (Glycine max) is a legume species belonging to the Fabaceae family. It is also known as “Soja bean.” Soybean is a major crop cultivated for oil extraction.

Countries like the USA, Argentina, China, India, and Brazil are the primary producer of this legume plant. (1) The oil is derived from the seeds of soybean, where drying, cracking, dehulling, and crushing the seeds are done. (2) 

Soybean oil is a significant source of saturated, monounsaturated, and polyunsaturated fats. It contains polyunsaturated fatty acids (omega-3 and omega-6 fatty acids), bioactive components like unsaturated fatty acids, phospholipids, tocopherol, and phytosterol. (3)

It also carries flavonoids, isoflavonoids, phenolic acids, phytoalexins, peptides, and saponins. (4) Vitamins like E, K, and choline are present in this legume. Iron and zinc are the minerals available. All these nutritional components possess anti-oxidant, anti-diabetic, anti-proliferative, anti-obesity, and anti-inflammatory properties. (5)

Soybean seeds are round in shape. The color of the seed coat ranges from yellow, green, brown, and black. The black and brown seeds store more flavonoids and anthocyanins than the yellow seeds. (6) The seed size ranges from 4 to 11 millimeters in height and 3 to 8 millimeters in width. (7) The aroma of soybean oil is fishy off-odor because of trimethalymanine (TMA). The taste of the oil is neutral. 

Soybean and their oil are great ingredients for the kitchen. Its oil is used in cooking and salad dressing. Soybean oil is also used as a mosquito repellant. Soybean itself is an excellent food for replacing meat and dairy products. (4) Flavored soymilk is an energy drink. Other products like tofu, soy sauce, and paste are prepared from soybean. Natto and tempeh are fermented soybean products. 

Nutritional Facts

Soybean seeds contain essential amino acids which a human body can’t make. (6) The oil is high in both healthy and unhealthy fats. Monounsaturated and polyunsaturated fats are known as healthy fats compared to saturated fats. (8)

A higher intake of healthy fat and a lower intake of unhealthy fat is preferred. Dietary fats reduce inflammation and protect the heart from chronic diseases like stroke, blood pressure, and diabetes. The analysis of this legume and the data of nutritional components present are (9,10)

Soybean oil contains saturated, monounsaturated like oleic acids, and polyunsaturated fats like linolenic acids in good quantity. Excessive consumption of saturated fats is believed to increase the risk of heart disease. Still, polyunsaturated and monounsaturated fats reduce inflammation and maintain cholesterol levels in the blood.

Lipids	Amount (per 100 grams)	Daily Adult Requirements
Total fat	100 g	60-80 g
Saturated fatty acids	14.9 g	–
Monounsaturated fatty acids	22.1 g	–
Polyunsaturated fatty acids	57.6 g	–

The oil is high in calories (900 kcal/100 g) which can promote weight gain. This oil is rich in vitamin E (12.2 mg/100 g), vitamin K (184 mcg), and choline (0.2 mg/100 g). Minerals like iron (0.05 mg/100 g) and zinc (0.01 mg/100 g) are also present.  

Phytosterols like stigmasterol (55.4 mg/100 g), campesterol (58 mg/100 g), and beta-sitosterol (153 mg/100 g) are also present in soybean oil. (11)

g-gram, mg-milligram, mcg-microgram, kcal-kilocalorie

Health Benefits

Soybean is an important protein and oil crop. The presence of flavonoids, phenolic acid, phytosterols, peptides, and saponins enhances the health benefits. The oil is believed to protect us from several heart and kidney diseases and prevent tumor cell formation.

1. Can support heart health: Soybean oil contains polyunsaturated fatty acids. Low-density lipoprotein (LDL), when collected in blood vessels, raises the chance of heart attack and stroke. Polyunsaturated fatty acids reduce the level of LDL and protect our heart health. (12)

2. Can improve eye health: Soybean oil is rich in omega-3 fatty acids. The antioxidant properties of healthy fats protect our eyes from free radical damage. Protection of eye cells helps to prevent chronic ocular conditions (cataracts, macular degeneration, color blindness, dry eyes, etc.) (13)

3. Can prevent diabetes: Flavonoids, isoflavonoids, and stigmasterol present in soybean oil control the transport of glucose in the blood. They control renal hyperfiltration and insulin sensitivity and function as antidiabetes agents. (14)

4. Can protect against cancer: Phytosterols in soybean oil possess anti-cancer effects. The oil prevents and protects against prostate, colon, and breast cancer. Isoflavone also reduces the growth of hormone-related cancers (ovary, testis, thyroid). (14) 

5. Can support bone health: The presence of vitamin K, iron, and phytosterols in soybean oil reduces the risk of Osteoporosis (a disease where weakening of bone and fracture is seen). It also prevents Osteopenia (loss of bone mineral density) in females. (15)

Despite benefiting our health, soybean oil still has its downfall. It can alter the thyroid function (cause hypothyroidism) in one with iodine deficiency. (14) Allergy and constipation can also be the side effects of soybean oil.