8 Reasons why should you avoid Soybean Oil in Cooking

Soybean oil is an edible vegetable oil that is derived from soybean, a legume that has a high amount of plant protein and oil.

Soymilk, soy curd and tofu are an amazing alternative to dairy products, and they have gained tremendous popularity in the vegan diet.

Soybean oil contains a high amount of polyunsaturated fatty acids, particularly omega-6 fatty acids, which can be harmful to the overall health.

Both omega-3 and omega-6 fatty acids are necessary for human health. But, in the case of soybean oil, the amount of omega-6 fatty acid is more than omega-3.

Such a hefty amount can up the production of inflammatory substances and boost the onset of diseases.

Is soybean oil healthy or if not why is soybean oil bad for you?

Let’s have a look at what research has to say about soybean oil, should we use it or eliminate it from our daily diet, still remains a huge question!

Soybean Oil Causes Insulin Resistance

Soybean oil has a high content of polyunsaturated fatty acids. Studies have found that a high soybean oil diet causes weight gain, insulin resistance and diabetes mellitus more than a high fructose diet alone.

Whereas, a high soybean oil and fructose diet can cause distinct changes in the genes involved in obesity and glucose metabolism.

This oil up-regulates the activity of genes that are involved in obesity and hyperglycemia. Soybean oil also increases the deposition of fat in the body, which in turn reduces the signaling of insulin receptors. Thus, the body produces more insulin to transport glucose from the blood to the muscles. Hence, soybean oil reduces insulin sensitivity and increases insulin resistance.

Besides this, a high intake of soybean oil causes weight as well as fat gain. The fat cells increase the production of free fatty acids in the body that causes beta-cell dysfunction and insulin resistance. Thus, individuals who are overweight or obese are at an increased risk of developing type 2 diabetes mellitus.

The study further found that though coconut oil is rich in saturated fat, it is still a healthier option as compared to soybean oil, which has a lower saturated fat content, but a higher polyunsaturated fatty acid content. (1)

Soybean Oil Causes Liver Damage

Soybean oil is not at all a safe option for individuals with fatty liver. Fatty liver is a condition in which, fat gets deposited in the liver and affects the structure and function of the liver.

An interesting study observed that the progression of the disease, inflammation and hardening of the liver takes place when a high cholesterol diet is combined with a soybean oil-based high fat diet rich in omega-6 polyunsaturated fatty acid.

Soybean oil increases the accumulation of cholesterol in the liver cells. PUFA present in the soybean oil increases the hepatic uptake of cholesterol as well as reduces its removal from the body. This impairs the functioning of the liver. PUFA further aggravates oxidative stress in the liver and causes the death of the liver cells. (2)

Soybean Oil Gives Rise To Inflammation

Inflammation contributes to all non-traumatic musculoskeletal diseases, thereby causing pain and disability in millions of people worldwide, says research. Hence, it is important to eliminate foods from the diet that gives rise to inflammation.

Studies have found that a high intake of soybean oil raises the level of inflammatory compounds in the body. These dangerous compounds can lead to a series of chronic diseases. This suggests that high levels of soybean oil can promote the body’s inflammatory response and increase the risk of developing diseases.

This cooking oil can up the level of TNF-α, an inflammatory compound that increases the level of LDL ‘bad’ cholesterol and accelerates the development of atherosclerosis.

Besides this, the high consumption of soybean oil also gives rise to acute inflammation and causes mortality from cardiovascular disease.

This shows that soybean oil is definitely not a healthy fat option. Hence, it is best to choose an oil with anti-inflammatory properties. (3)

Soybean Oil Boosts Oxidative Stress

Overproduction of free radicals in the body leads to oxidative stress, which is the root cause of various diseases and disorders.

A high intake of soybean oil increases the production of free fatty acids in the body. These free fatty acids stimulate the body to produce more reactive oxygen species, which can induce the oxidative stress mechanism.

Besides this, soybean oil contains vitamin E, which is a powerful antioxidant, but this antioxidant is destroyed when soybean oil is heated at high temperatures. Hence, loss of this antioxidant may cause the oxidized oil to produce more free radicals in the body.

Health Tip: If at all you are using soybean oil, do not use it for frying. Cooking oils when heated to a high temperature for frying foods, can lead to loss of natural antioxidants present in them. This can make the oil unstable and unsuitable for overall health. (4)

Soybean Oil Increases the Risk Of Cardiovascular Disease

Various chemical reactions take place in soybean oil when it is heated at a high temperature. The tendency of soybean oil to get oxidized during this phase is quite common and harmful for heart health.  

Excess production of reactive oxygen species reduces the supply of oxygen towards the heart muscles and finally causes the death of that tissue. It also changes the way the heart functions and has an overall negative impact.

Moreover, soybean oil is rich in polyunsaturated fatty acids (PUFA), particularly linoleic acid, an omega-6 fatty acid. Studies have indicated that omega-6 containing vegetable oils increases the risk of cardiovascular diseases.

Linoleic acid causes oxidation of the LDL ‘bad’ cholesterol, which results in the formation of plaque or clot in the arteries. Linoleic acid is also pro-inflammatory, which damages the arteries, promotes the death of heart tissue and finally cardiac arrest.

One interesting study also observed that individuals who have died from sudden cardiac death have more linoleic acid and less omega-3 polyunsaturated fats in their arteries that supply blood to the heart.

Hence, it would be wise to reduce your intake of soybean oil and replace it with cooking oil that contains a good amount of heart-protective omega-3 fat. (5, 6)

Soybean Oil Promotes Obesity

It is very well-known that obesity is the root cause of various health problems. Recently, studies have examined that a diet rich in soybean oil promotes fat deposition as well as obesity.

As compared to a diet made from coconut oil, soybean oil is more obesogenic. Such an effect of soybean oil is attributed to the presence of ‘linoleic acid’ in it. In the body, linoleic acid is converted to arachidonic acid, which induces inflammation and increases the deposition of fat in the body.

So, if you are trying to lose weight, do not introduce soybean oil to your diet. (7, 8)

Soybean Oil May Hamper the Immunity

Fatty acids and different sources of lipids have an impact on the functionality of the immune system. Soybean oil may affect some immune parameters, owing to its high content of omega-6 polyunsaturated fatty acid. This results in a decrease in antibody response against toxins or foreign substances, that may be harmful to the body.

Omega-6 fatty acids also reduce the production of immunoglobulins, proteins that fight against the infections and boost the immune system.

Dietary fat can modulate the immune system by altering the gene expression and increasing the production of arachidonic acid. Arachidonic acid is toxic to the cells and it reduces the activation of white blood cells too. This hampers the immune system and leads to poor and weak immunity.

A high intake of soybean oil also stimulates the production of certain hormones, that are immunosuppressive. These hormones inhibit the production of antibodies and decline the functionality of immune cells too.

Hence, a high intake of soybean oil may suppress the ability of the body to produce antibodies and fight against infections. (9)

Soybean Oil May Alter the Lipid Profile

Soybean oil increases the concentration of free fatty acids and cholesterol in the body. It increases the level of LDL ‘bad’ cholesterol and reduces the level of HDL ‘good’ cholesterol in the blood.

Besides this, a polyunsaturated fatty acid present in soybean oil reduces the removal of cholesterol from the body. Studies have also found that soybean oil increases the level of triglycerides in the blood.

Therefore, soybean oil may not be the right choice for individuals with altered lipid profiles.

Final Verdict:

Soybean oil can be used in small amounts for cooking. This oil may not be a healthy choice for individuals with insulin resistance, altered lipid profile, heart diseases and liver problems.

Plus, heating soybean oil to high temperatures may cause the formation of certain chemicals that are dangerous for human health. Hence, soybean oil should never be used for frying foods.

Choose oils that contain a good balance of omega-3 and omega-6 fatty acids. Moreover, opt for oils that are unrefined or minimally processed. Soybean oil is refined oil, which undergoes various steps of processing and chemical refining. The addition of various chemicals to soybean oil can also be dangerous for overall health.