They’re everywhere. Processed, refined vegetable oils seem to be hiding in just about everything we eat nowadays. They are hidden behind names which tend to seem healthy such as sunflower, soybean and cottonseed oil to name a few. But don’t let these names fool you, vegetable oil is bad for you! But what makes these oils so bad? I mean after all you do need fat right?
Well that is absolutely correct! You do need fat and fat is very good for you, in fact it is essential for health. However fat is a bit tricky because it's one of those things where it's either really good or really bad for you. And it may seem hard to decipher between the two if you’re not somewhat of a nutrition or health nerd like myself. But don’t stress! I’m here to help break this down for you in the easiest way possible!
So what are processed vegetable oils? Where do they come from? Why are they so bad? And what makes them so much different from the healthy oils such as olive or coconut oil?
Common Names of Processed Vegetable Oils to Avoid:
Nonstick cooking spray
Palm kernel oil
Any form of hydrogenated oil
Any form of trans fats
To start with, processed vegetable oils are unsaturated oils which are extracted from seeds, grains and legumes. One of the problems here is these plants do not like to give up their oils easily. This means that in order to extract these oils, there must be extensive processing through the use of high-heat, mechanical extraction, industrial chemicals, deodorization and toxic solvents. When we consider that healthy oils can be cold-pressed and require very minimal processing, it’s not hard to see the difference.
Another negative when it comes to processed vegetable oils is their high profile of omega-6 fatty acids. Omega-6s are essential in small doses, however the modern introduction of these oils has led to a huge increase in their consumptions and a disruption in the ratio between these and omega-3s. While omega-3s are anti-inflammatory oils, omega-6s are pro-inflammatory. These two oils are meant to work together in a ratio between 1:1 and 1:4, however the ratio for those consuming a typical western diet now sits at about 1:16. This out-of-balance increase in omega-6s creates the perfect storm for chronic inflammation which may eventually lead to many degenerative diseases such as cardiovascular disease, metabolic dysfunction, certain cancers and autoimmune disease.
In addition, processed vegetable oils are susceptible to oxidation due to the multiple double bonds they contain. This means they are much more prone to reacting with oxygen and heat. And unlike the more healthful oils such as olive oil, they contain very little vitamins and phytochemicals which help to prevent oxidation. So what is so bad about oxidation? Well, when these processed vegetable oils oxidize they create many toxic and potentially carcinogenic products. Not something any of us want to mess around with!
It is also important to note that it is not just processed vegetable oils which can become oxidized. Healthy unprocessed polyunsaturated oils (found in fish, walnuts, sunflower seeds and flax seeds or oil) are very susceptible to this oxidization, however monounsaturated fats (like olive or avocado oil) can also be susceptible. It is important to store and cook these oils / fats appropriately to avoid them becoming oxidized.
The takeaway here is to avoid all processed vegetable oils! Pay attention to food labels where they are likely to be hiding. They are not worth the negative effects on our health. Instead switch them out for healthy unprocessed, cold pressed oils and always make sure to cook and store each oil appropriately.