Understanding the Facts and Myths About Seed Oils

Myth: Seed oils are bad for you

The myth that has been gaining popularity on social media is that seed oil is bad for you. What's commonly said is that oils like canola, rapeseed, soybean, and grapeseed oils increase inflammation. The reason? These oils have a high amount of omega-6 fatty acids. In some animal studies, rodents that were fed diets high in omega-6 fatty acids showed an increase in inflammation^1. However, there are no human studies that show this to be true. In fact, when looking at multiple studies, people consuming these plant-based oils had LESS inflammation and lower “bad” cholesterol, than those that ate more butter or lard. Let us dive a little deeper into this topic.

Understanding Seed Oil Benefits

Are you familiar with omega-3 fatty acids? This is the beneficial polyunsaturated fat found in fish but also found in flax seeds and walnuts. These fatty acids have been shown to be heart healthy, help prevent inflammation, and lower triglycerides, which is a type of fat found in our blood. Omega-6 fatty acids is another type of polyunsaturated fat which is found in safflower oil, sunflower oil, sunflower seeds, walnuts, corn oil, soybean oil, and pumpkin seeds. The fear of these omega-6 fatty acids is that the most prominent one, linoleic acid, changes into another fatty acid, arachidonic acid (ADA), which could increase inflammation. However, science does not support this. Linoleic acid does a poor job in converting to this ADA. There are multiple studies that look at increasing and decreasing amounts of linoleic acid in diets having little to no impact on the total amount of ADA in our blood. On top of that, ADA has both inflammatory AND anti-inflammatory properties, making this argument a very weak one.

Studies show that both omega-3 and omega-6 fatty acids are beneficial to our heart and health. Many studies show that as consumption of omega-6s goes up, the risk of heart disease goes down. When replacing saturated fat with omega-6 fatty acids, the risk of heart disease dropped by 24%¹. We know that omega-3 fatty acids are good for us, but most Americans do not eat enough omega-3s to achieve all the cardio-protective benefit. Most of us consume well over the recommendation for omega-6s. Seed oils are used often in highly processed foods like baked goods, chips, salad dressings, mayonnaise and candy. Instead of focusing on removing seed oils from your diet, try to increase your intake of omega-3s and limit the chips, baked goods and candy. Focus on increasing the intake of baked or grilled fish to 1-2 times per week and adding walnuts and flaxseeds into your diet.

The truth of the myth

When oils are heated to high temperatures for a long period of time, as is the case of deep-frying food, the oils break down and convert to trans fats. These fats DO become inflammatory. They also increase our risk for heart disease by increasing the “bad” cholesterol. When we use seed oils for cooking like roasting, sauteing or even pan frying, the oil is not reaching the same hot temperature that convert the oils to trans fats. If you are deep-frying at home, it is important to discard the oil after use, and not reuse that oil.

Takeaways

There is no need to fear seed oils. They are an inexpensive, easily available, heart-protecting unsaturated fat. There are no good studies supporting the claims that they are bad for us. More important than reducing our intake of omega 6s is the need to increase omega 3s and decrease our intake of saturated fats and fried foods.

Sources

1. Idz. (2024). Saturated facts: The Real Science Behind Diet Myths. Penguin Life.

The article provides information designed to complement your personal health management. It does not provide medical advice and not meant to replace professional medical advice. Linking to other websites does not imply any endorsement of the material on such websites.