Seed oils have faced their fair share of scrutiny, being called things like “The Hateful Eight”. There are always new trends in food and nutrition, with people constantly searching for what could be added or taken away from their diet to make them healthier. The myth that seed oils are harmful, toxic, and should be completely removed from your diet is an ongoing trend in nutrition these days. Nutrition often isn’t that simple. Let’s do some myth-busting around seed oils because they don’t deserve the hate they’ve received from social media.
Seed oils are comprised of eight main kinds: canola oil (aka rapeseed oil), corn oil, cottonseed oil, grapeseed oil, soybean oil, sunflower oil, safflower oil, rice bran oil and peanut oil. Seed and vegetable oils have been around for a long time. China and Japan produced soybean oil as early as 3000 B.C. Canola was bred through conventional plant breeding methods in Canada during the 1960s and ’70s(1) to significantly reduce the levels of erucic acid and glucosinolates in the parent rapeseed for use in food.
One of the biggest myths about seed oils is that the omega-6 fatty acids in them are toxic and unhealthy. There are two families of polyunsaturated fats, omega-3 and omega-6, suitable for the heart and body. Your body needs both of these to function but can’t produce them. This means that we need to get them from our diets. Seed oils are a great source of both of these, especially omega-6 fats. In the past, researchers have suggested that a diet too rich in omega-6 fats can cause inflammation, which can lead to arthritis, heart disease, stroke, type 2 diabetes, and more. More recent research has shown that any inflammation associated with omega-6 fats has not been shown to be harmful (2). In fact, fats of all kinds are essential in your diet. They provide us with energy, support cell function, help us absorb nutrients, support hormone health, and more.
Another myth of seed oils is that they’re bad because you don’t often know when you're consuming them. Seed oils are frequently used in processed foods. Ultra-processed foods are generally known for not being healthy. Still, it’s impossible to blame seed oils solely, especially since these ultra-processed foods contain many other things, like added sodium or sugar.
Seed oils have also come under fire thanks to the methods used to produce them (3). Seed oils need to be refined, which requires more processing than olive oil, which simply requires olives to be pressed. Seed oils are produced by using a few different steps. First, the seeds are pressed to extract the oil. Then, the oil is refined. During the refining process, oils are heated to a temperature that drives off volatile compounds, which makes the oil more stable. This is why refined oils have higher smoke points and a longer shelf life than unrefined oils. That temperature is lower than the temperature necessary to oxidize the oil. After this, the oil is deodorized. Deodorization is a steam distillation process that drives off the unwanted aldehydes, ketones, alcohols and short-chain fatty acids that cause undesirable odors. Careful execution of this process improves the stability and color of the oil while preserving its nutritional value. After the steam distillation process, the oil is conditioned under nitrogen to prevent oxidation.
While seed oils are not always healthy if you consume them too much, they are a healthy addition to your diet if you use them in cooking (how they’re meant to be used). Seed oils can also help you enjoy more foods. Having a choice between different fats to use for cooking (butter, olive oil, seed oils, etc.) allows you to find the flavor that fits best with what you’re cooking. If using any of these fats helps you enjoy more vegetables and other nutritious foods, it's a healthy addition to your meal.
Seed oils are not the villains they are made out to be. They are a safe, versatile, and healthy option. They provide necessary omega-6 fatty acids and are produced using safe methods that extend the product's shelf life. Social media is making seed oils out to be something terrible that you should stop consuming. This isn’t true; seed oils aren’t bad for you or toxic. Don’t listen to all the fearmongering trends you see online; the internet doesn’t always know what is healthy or nutritious.
(1) https://www.canolainfo.org/canola/the-history-of-canola-oil.php
