Fresh and Trending: Seed Oils
It seems like every day there’s new information about nutrition circling the internet. One of the most recent hot topics is seed oils. Seed oils have come into the spotlight being targeted for being “toxic” and “poisonous”. The top oils being called out include canola, corn, cottonseed, soybean, sunflower, safflower, grapeseed and rice bran oil. This group has also been referred to as “The Hateful Eight”. Pretty catchy right? Almost like an old Western movie.
The accusation of seed oils being “toxic” relies heavily on the thought that omega-6 oils (that are present in seed oil) break down into toxins when cooking. In theory these toxins cause inflammation and contribute to chronic illness. But are they actually the bad guys? Or is this shoot-out all a misunderstanding?
Omega-3 and Omega-6
Both omega-3 and omega-6 fatty acids are classified as polyunsaturated fats. Polyunsaturated fats are known for playing important roles in overall health.
Omega-3s are specifically known for being anti-inflammatory by inhibiting production of specific molecules that are involved in the inflammatory process. Omega-6s while they are not generally considered anti-inflammatory, they are suspected to play a role in the anti-inflammatory process. An Omega-6 fatty acid called linolenic acid has anti-inflammatory properties. Additionally, linolenic acid is an essential fatty acid which means it is a fatty acid that your body needs, but the body cannot make. So, it is essential that you consume it in your diet.
Processing and Cooking
As the name implies, seed oils are made by extracting oil from a seed rather than the fruit, like avocado and olive oils. There are two ways that oil is extracted from the seed, cold-pressing and refining.
Cold-pressed oils are created by pressing the seeds. These oils retain more odor and flavor but have a low smoke point, meaning they degrade when cooked at high heat (sauteing or frying).
Refined oils are processed further using chemical solvents to extract more oil and filter it. This type of processing also helps remove strong flavors and colors. Solvents used during the refinement process are not present in the final product and does not pose health risks to consumers. This is the most common method for obtaining seed oils due to its affordability, shelf life, neutral flavor and high smoke points.
In addition to knowing how to seed oils are processed and which ones are best to be used in certain types of cooking. It is important to note that seed oils are commonly used in many ultra processed foods. This being said, seed oils are not red flag ingredients for every individual when looking at ingredients in ultra processed foods. It is important to talk with your doctor or a registered dietitian before making any big changes to your diet or lifestyle.
Do Seed Oils Cause Cancer?
There is very limited research conducted on the impact of consuming seed oils and cancer risk. However, there has been a significant amount of research conducted on how the reheating and reusing of all types of oil have led to increased risk to colon cancers. It is suspected that due to reheating and increased degrading of the oil it is more likely that carcinogens can develop.
Cooking with any oil and being exposed to the fumes for prolonged periods of time have also been linked to a higher risk of lung cancer.
