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Opting for oils with a more balanced fatty acid profile or those less prone to oxidation may be a healthier choice for long-term heart health.
When sunflower oil is subjected to prolonged heating, such as during deep-frying, its free fatty acid content increases, making it more prone to rancidity upon exposure to air
Sunflower oil has long been marketed as a healthy cooking option due to its high polyunsaturated fatty acid (PUFA) content. However, much research paints a more nuanced picture, raising significant concerns about its potential risks to heart health and overall well-being—particularly when consumed in refined and heated forms. Like most seed oils, sunflower oil is rich in omega-6 fats, which, while essential in moderation, can become a source of inflammation and oxidative stress when consumed toin excess. Dr Varun Bansal is Consultant Cardiac Surgeon, Indraprastha Apollo Hospitals shares all you need to know:
Why Sunflower Oil Deserves a Closer Look
One of the primary concerns with sunflower oil lies in its high omega-6 fatty acid content. While omega-6 fats are crucial for the body, an imbalanced omega-6 to omega-3 ratio—common in diets heavy in sunflower oil—can fuel chronic inflammation. Furthermore, sunflower oil’s chemical structure makes it highly susceptible to oxidation when exposed to prolonged heat or sunlight. This oxidation results in the production of harmful byproducts such as toxic aldehydes and hydroperoxides, which have been linked to cardiovascular diseases, neurodegenerative disorders, and even cancer.
Below, we explore three key long-term effects of regularly consuming sunflower oil:
1. Increased Risk of Chronic Inflammation
Research shows that the omega-6 fatty acids in sunflower oil serve as precursors to pro-inflammatory compounds like prostaglandins and leukotrienes. While inflammation is the body’s natural response to injury or infection, chronic inflammation—often fuelled by dietary factors—is a major contributor to cardiovascular diseases such as atherosclerosis and hypertension.
Adding to this risk are the oxidative byproducts formed when sunflower oil is heated during cooking. These compounds not only exacerbate inflammation but can also damage blood vessels, compounding the risk of heart disease over time.
2. Accumulation of Toxic Compounds
When sunflower oil is subjected to prolonged heating, such as during deep-frying, its free fatty acid content increases, making it more prone to rancidity upon exposure to air. This process generates toxic substances like aldehydes and hydroperoxides. Studies link these compounds to a host of health issues, including neurodegenerative diseases and cancer.
Deep-frying, especially when the same batch of oil is reused, amplifies the presence of these harmful substances. Furthermore, heating sunflower oil significantly reduces its antioxidant content, such as polyphenols and flavanols, which play a protective role in neutralising oxidative damage. It’s worth noting that while storing sunflower oil in airtight containers can prevent exposure to air, it cannot mitigate the damage caused by repeated heating.
3. Oxidative Stress and Nutrient Loss
Sunflower oil’s susceptibility to oxidation is a double-edged sword. On one hand, its high PUFA content is considered a nutritional advantage. On the other hand, these PUFAs are highly vulnerable to thermal oxidation when exposed to high cooking temperatures or prolonged sunlight. This process not only depletes the oil’s beneficial antioxidant properties but also generates free radicals—unstable molecules that damage cells and tissues.
The resulting oxidative stress accelerates ageing and heightens the risk of degenerative conditions, including heart disease. Numerous studies have implicated lipid peroxidation—a direct result of heating PUFAs like those in sunflower oil—as a factor in various chronic diseases.
While many edible oils have a reputation as healthy cooking mediums, it is essential for consumers to approach their use with caution. For example, the high omega-6 content of sunflower oil, combined with its susceptibility to oxidation and the formation of toxic byproducts during heating, makes it less heart-friendly than commonly perceived. Opting for oils with a more balanced fatty acid profile or those less prone to oxidation may be a healthier choice for long-term heart health.
