Considered a healthy choice by many people, due to their low saturated fat content, consumption of highly processed seed and vege oils has increased dramatically in the past century. The shortened version of this article is: Don’t touch processed seed and vegetable oils. Read on for a more in-depth look at why.
Highly-processed vs. Virgin oils
We’re talking about the oils that are extracted from sources like soybean, corn, cottonseed, sunflower and a few others. These are quite different than cold pressed or ‘virgin’ oils from sources like olives or coconut. Firstly, the way these oils are made includes bleaching, deodorizing and the highly toxic solvent hexane. Processed seed and vege oils are also very high in Omega-6 polyunsaturated fatty acids. As you know when the Omega-6 to Omega-3 ratio shifts too high in favor of Omega-6, bad things happen in the body. The excess Omega-6 can cause inflammation1. Inflammation is linked to cardiovascular disease, cancer, diabetes, arthritis and more. Studies also show that Omega-6 fatty acids may increase death from heart disease.2-3
Cooking fats, the key is stability
When it comes to cooking, we run into even more problems. It turns out that heat changes things. Trans-fats can be created from some seed and vege oils when they are exposed to high temperatures like frying. Trans-fats4 are linked to all sorts of horrible diseases, including cardiovascular disease, obesity, cancer and diabetes.5-6 It all comes down to stability. The more saturated fat content in a fat, the more stable it is. The more stable a fat is, the better it is for high heat cooking. This is why coconut oil, at well over 80% saturated fat, is great for high heat cooking.
What’s the best way to choose fats?
Look at these three things:
1. How they are made. Choose least processed options, the unrefined or 'virgin' oils.
2. Fat composition, more saturated fat content means less heat damage when cooking.
3. Smoke point, how hot it gets before it smokes! But look at fat composition first.
Try cooking with these fats (see image above) instead of processed vege and seed oils: Coconut oil, butter (or clarified butter called Ghee), and animal fats like lard.
Don’t cook with these processed oils at high heat, they are not stable. In fact, we recommend you avoid them all together. Stay away from margarines too.
- Soybean oil
- Canola oil
- Corn oil
- Safflower oil
- Cottonseed oil
- Sunflower oil
- Rapeseed oil
- Rice Bran oil
Olive oil, virgin, is still an excellent choice for lower heat cooking. It’s attributed to the amazing health of the mediterrean diet7.
Remember, processed seed & vege oils are snuck into a lot of foods. If you really want to avoid them, always read the label!
More on fats:
Fats 101 - Forget everything you’ve ever heard about low fat diets.
Contributing editors: Diana Archer-Mills, Sarah Wakeman BSc. Biology PGDip. Food science, Kris Gunnars.
Heading up our nutrition project is Dr. Jackie Mills (B Phys Ed, MBCh B, Dip Obstetrics), a specialist in nutritional medicine, an obstetrician and general medical practitioner. Jackie completed her post-graduate studies in nutrition at the Australian College of Nutritional and Environmental Medicine (ACNEM) and has practiced nutritional medicine for 25 years. As Les Mills’ Chief Creative Officer, Jackie is responsible for the development of all LES MILLS™ exercise programs.
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