World Heart Day 2019: Is Refined Oil Good For Heart Health?

Tuesday, September 24, 2019, 17:41 | Reviewed By Arya Krishnan

World Heart Day is observed on 29 September every year. Cooking with the right kind of oil is critical, as it makes all the difference to the food in terms of taste, flavour and its health quotient. With the endless choices on the store shelves, it can become difficult to choose the right one. One of the right (and easy) ways to choose the right kind of cooking healthy (that is healthy too) is by choosing a liquid that remains liquid instead of solid at room temperature.

From traditional cooking oil to refined oil, we are given the freedom to choose the best out of the lot. However, not every type of oil can be beneficial for your overall health. Today, we will take a look at the link between refined oil and heart health. After all, your heart is the most affected by fatty acids.

So, What Is Refined Oil?

Refined oil is nothing but the 'refined' version of the normal oil. The process of refining involves chemicals, which in certain quantities, are harmful to our health. The 'purification' of the oil is done by treating it with acid, alkali or by bleaching. Refined oil is also neutralized, filtered or deodorized. All of these processes involve chemicals such as hexane ^[1] .

There are various kinds of refined vegetable-based oils, including canola or rapeseed oil, soybean oil, canola oil, corn oil, sunflower oil, safflower oil, and peanut oil. Refined oils are stable at higher temperatures.

Various studies have pointed out that refined oil is the most commonly used type of cooking oil, as people tend to chose it for cooking, due to its 'refined' nature. Although the Scientific Panel on Oils and Fats at Foods Safety and Standards Authority of India (FSSAI) has said that refined oils are safe to use as cooking oil, the negative effects of the oil subdue its plausible positive effects ^[2] .

The extensive process of refining converts the oil into trans fat through oxidisation, which is then deodorised to rid off the rancid smell of trans fat ^[3] . Whatever the source of the oil is, be it avocado, sesame seeds or olives, refined oil is subjected to a long process of purification which in irony is hampering with the quality of the types of oil. Some refined oils undergo the process of hydrogenation which further damages the fatty acids in the oils, creating trans fatty acids ^[2] ^[4] .

Side Effects Of Refined Oil

The intensive chemical and mechanical process involved in refining does not improve the quality of the oil. Refined oils are high in inflammatory omega-6 fatty acids and made using toxic chemicals which can increase body inflammation, elevate blood triglycerides, and worsen an impaired insulin response. Studies have linked consumption of refined oil to diabetes, cancer and heart disease ^[5] .

The sodium hydroxide used in the refining process can cause ulcers, gastroenteritis and other gastric disturbances. The chemicals are also prone to develop respiratory diseases and hinder with the process of blood circulation to your brain.

Is Refined Oil Good For Your Heart?

Refined oils are extracted using solvents, which then undergoes a mechanical process of bleaching, deodorising and so on. This process reduces the flavour, colour and odour of the original oil and even some of the beneficial antioxidants too. A lot of studies have explored the impact of refined oil consumption on one's heart health. And, it is asserted that, in comparison to animal fats, refined vegetable oils are more prone to cause heart diseases. One of the studies compared the consumption of butter with that of refined vegetable oil, and it was found that the latter increased the risk of cardiovascular diseases ^[6] ^[7] .

Packed with an abundance of trans fat, refined oil has been shown to elevate the risk of heart attack and death from heart diseases. However, this view is contradicted with various companies labelling refined oil as being heart-healthy. This is because studies link polyunsaturated fat to a reduced risk of heart problems, compared to saturated fat. However, an increasing number of studies link refined oils with elevated risks of heart diseases due to the omega-6 fat in it ^[8] .

The contradictory views on the refined vegetable oil and heart health can be rather confusing, with scientific views going back and forth between its positive and negative impact on heart health. One such study revealed that replacing saturated fat with polyunsaturated fat reduces the risk of heart problems by 17 per cent, but it has no significant effects on the risk of death from heart disease ^[8] .

Traditional Cooking Oil Is The Better Option!

A recent study on the link between refined oil and traditional cooking oil asserted that ghee, coconut and mustard oil are the healthier and better options instead of refined oil. A study published in the Indian Heart Journal (IHJ) stated that it is advisable to avoid refined oil - which loses its quality and generates toxic chemicals when being refined ^[9] ^[10] .

The easy degradation of these refined oils is unhealthy for your cardiovascular health, as well as your overall health ^[11] .

On A Final Note...

Compared to any other type of oil, refined oils increase the risk of heart disease the most. However, a moderate intake may not pose extensive harm to your health. But, to be on the safe side, adopt healthier options such as EVOO (Extra virgin olive oil), olive oil, coconut oil, peanut oil, soybean oil and organic butter. And avoid hydrogenated oils at any cost. After all, anything and everything consumed in large quantities can never be good for your health!

FAQs On Refined Oil & Heart Health

Q. What is the healthiest cooking oil for your heart?

A. Nutrition and cooking experts agree that one of the most versatile and healthy oils to cook with and eat is olive oil, as long as it's extra virgin. Extra light olive oil and sunflower oil are suitable for deep frying because of their high smoke points. And olive is the best option for shallow frying.

Q. Is olive oil safe for heart patients?

A. Extra virgin olive oil is a great source of monounsaturated fatty acid and has shown to help reduce one's risk for heart disease ^[12] .

Q. Is sunflower oil bad for your heart?

It supplies some monounsaturated fat (20 per cent) and is low in saturated fat (11 per cent), making it an overall heart-healthy option ^[13] .

Infographics by Sharan Jayanth

View Article References

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[2] Hashempour-Baltork, F., Torbati, M., Azadmard-Damirchi, S., & Savage, G. P. (2016). Vegetable oil blending: A review of physicochemical, nutritional and health effects. Trends in Food Science & Technology, 57, 52-58.
[3] Sharma, S. K., Shukla, D. D., Khatri, K. K., & Rajput, N. S. (2017). Performance evaluation of diesel engine using biodiesel fuel derived from waste cooking refined soyabean oil. Int. J. Mech. Prod. Eng. Res. Dev, 7, 103-110.
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[6] Schilling, R. (2016). Avoid That Heart Attack.
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[13] Kleber, M. E., Delgado, G. E., Lorkowski, S., März, W., & von Schacky, C. (2015). Trans-fatty acids and mortality in patients referred for coronary angiography: the Ludwigshafen Risk and Cardiovascular Health Study. European heart journal, 37(13), 1072-1078.