Sunflower Oil

Is It Good or Bad for You?

What is sunflower oil?

Sunflower oil, or sunflower seed oil, is extracted from sunflower seeds. Like most vegetable oils, it is available in both cold-pressed and refined forms. Cold-pressed, unrefined sunflower oil is relatively rare compared to refined oil. It has a low smoke point of 160°C (320°F) and is best suited for low-heat applications such as salad dressings for its flavourful taste. On the other hand, refined sunflower oil has a high smoke point of 226°C – 246°C (440 – 475°F), making it one of the most popular vegetable oils employed for high-heat cooking, including sautéing and deep-frying.

Types of sunflower oil

Sunflower oil is mainly divided into 3 types based on the amount of oleic acid and linoleic acid present in them:

 

High-Oleic Sunflower Oil

High-Oleic Sunflower Oil is very high in oleic (monounsaturated) acid, with a minimum 80% oleic acid, around 10% polyunsaturated linoleic acid, 10% saturated fat and trans-fat free. This oil is preferred by food manufacturers because of its neutral taste profile, remains stable without the need for hydrogenation (hence no trans-fats are produced) and will not go rancid in long-term storage. This type of oil is more expensive and is ideal for frying, baking and other high-heat applications.

 

 

Mid-Oleic Sunflower Oil

Mid-Oleic Sunflower Oil is the most common type of sunflower oil, which contains around 65% of oleic acid, 25% linoleic acid and 10% saturated fat. This oil preserves sufficient levels of linoleic acid to remain an excellent dietary source, but the relatively high levels of oleic acid make it less prone to rancidity and breaking down, eliminating any need for hydrogenation or generation of trans-fats. This type of oil is available in large volumes and its reasonable price is competitive with other oils like canola and soybean oil. This oil is often used in snacks with a healthier focus. 

 

Linoleic Sunflower Oil

Linoleic Sunflower Oil is considered one of the least healthy types of sunflower oil, in comparison to high oleic oils. This type of oil contains around 70% linoleic acid, which is one of the essential fatty acids in the human diet. Another 20% is in monounsaturated fat (oleic acid), and the remaining 10 to 11% is saturated fat. Linoleic oil requires hydrogenation (which could produce trans-fats) to be stable for frying. This kind of sunflower oil is used in margarine, shortening, and is also available as liquid salad oil. It is now produced in very small volumes, due to its limitations in fried foods. 

 

Nutrition facts

Fatty Acid Breakdown of mid-oleic sunflower oil, which is typically the sunflower oil that you will buy at a retail store or supermarket. 

Saturated: 10%
Monounsaturated (e.g. omega-9): 65%
Polyunsaturated (e.g. omega-3, omega-6): 25%

  Omega-3: Omega-6 ratio = 1 : 12

Benefit

 

Refined sunflower oil lacks nutrients such as vitamin E and polyphenols, compared to its unrefined counterpart. Among the health benefits of unrefined, cold-pressed sunflower oil are: 

  • Promote heart health:

Sunflower oil helps improve blood lipid profile. It effectively reduces serum cholesterol, LDL (bad) cholesterol and triglyceride levels, while increasing HDL (good) cholesterol1, thereby reducing the risk of cardiovascular disease. The cholesterol-lowering effect of cholesterol may be attributed to the phytosterols, a compound that blocks cholesterol absorption by the body. 


  • Provide antioxidant protection:

Sunflower oil is rich in vitamin E, which serves as an antioxidant in the body2Antioxidant fights free radicals – the compounds that are harmful if their levels become too high in the body. Free radicals have been linked to various diseases, including poor immunity, heart disease, diabetes and cancer. 


  • May protect gastrointestinal tract:

When sunflower oil is used together with NSAIDs (nonsteroidal anti-inflammatory drug), it helps reduce gastric damage, an adverse side effect of the drug3.

 

  • May help fight cancer:

In a mouse skin tumour model, sunflower oil offers 40% protection against cancer, which may be attributed to the sesamol in the oil4.

The drawbacks

 

  • Imbalance omega-3 to omega-6 ratio 

    Sunflower oil contains far more omega-6s than omega-3, with omega-3 to omega-6 ratio 1 : 12. Modern lifestyle diet is already high in omega-6 fatty acids. Excessive intake of omega-6s can trigger the production of pro-inflammatory chemicals in the body5, which may increase the risk of certain chronic diseases, including arthritis, asthma, heart disease and cancer. If you are using sunflower oil, make sure you eat plenty of omega-3-rich foods such as fatty fish, chia seeds, flaxseeds, walnut etc. Alternatively, you may replace it with other cooking oils that are high in omega-3s, such as camelina oil and flaxseed oil

 

  • Refined sunflower oil is not good for health

    Refined sunflower oil goes through many different processes that involve chemicals and high temperature in the manufacturing process. The amounts of processing will damage the beneficial nutrients that it originally contained. Furthermore, polyunsaturated fatty acids may oxidise and turn into trans-fats (which are harmful) in the refining process. Nevertheless, refined sunflower oil has a high smoke point, which make it ideal for high-heat cooking.

 

  • Cold-pressed sunflower oil has low smoke point 

    Unrefined, cold-pressed sunflower oil has a low smoke point of 160°C  and should not be used for high-heat cooking, such as deep frying or grilling. It is more suited for salad dressings and low-temperature cooking, such as steaming and simmering. Cold-pressed oils are more nutritious to the body than the highly refined oils, besides retaining the original flavours that would enhance the taste of food. 

References:

1. Med J Islam Repub Iran. 2017; 31: 5.

2. Food Chemistry. 2002; 76(4): 461-468. 

3. Eur J Pharmacol.2008 Sep 4;591(1-3):300-6. 

4. Pharmacol Res. 2002 Jun;45(6):499-505.