The Controversial, Not So Controversial Canola Oil

One brilliant reader suggested that I do some research on canola oil as a follow-up to that article. So here we are today looking at the controversy surrounding canola oil.

I have to say that initially, I wasn’t too sure what the reader’s suggestion was all about. As far as I knew, there was nothing wrong with canola oil. I was even convinced that the oil is beneficial. Turns out a lot is going on with this oil and there is some debate on whether it’s good or bad.

A brief history

Canola oil is the product of rapeseed oil modification. Canadian scientists undertook the modification to make the oil safe for human consumption. In its original state, rapeseed oil contains erucic acid and glucosinolates.

Erucic acid has links to heart muscle damage. Glucosinolates prevent the body from absorbing iodine and also give the oil a bad taste. The genetically modified oil created by the scientists is low in both glucosinolates and erucic acid. So what’s the deal with this oil?

The good…

Canola oil has not always been so popular. It became popular after some research showed its positive effect on heart health, insulin sensitivity, and overall well-being.

• Canola oil is high in monounsaturated fat (about 63%). The monosaturated fat is nearly as high as that in olive oil.
• Canola oil has phytosterols that absorb cholesterol.  According to research, the oil lowers both LDL cholesterol and triglycerides while maintaining the levels of HDL cholesterol. When you consider that cholesterol remains a common risk factor for three of the world’s deadliest diseases – heart disease, stroke, and type 2 diabetes – it’s easy to see why we went crazy for the oil.

In the past, canola oil also boasted of low levels of saturated fat, but this fat is quite irrelevant now.  Besides these health benefits:

• canola oil has a low smoke point which makes it ideal for frying
• many people view it as one of the affordable healthy oil options.

Currently, canola is the third most-produced oil in the world. It’s very popular in China and India where many people consider it part of a healthy lifestyle.

Canola oil comes with a bit of baggage.

Some unbalanced proportions

One of the supposed benefits of the oil is its 28% polyunsaturated fat which includes both omega-3 and omega-6 fatty acids.

Although both omega-3 and omega-6 are vital for body functions, failure to balance the two can be problematic. A 1:1 balance is ideal, but research has shown that most diets do not provide this balance. For example, a typical Western diet has an estimated omega-3/omega-6 ratio of around 1:15.

Canola oil is high in omega-6. In fact, the oil is often touted as an amazing source of omega-6. But instead of making canola oil consumption good, the high levels of omega-6s compared to omega-3s can lead to an imbalance. This imbalance can lead to increased inflammation, Inflammation, in turn, has links to various chronic conditions such as heart disease, obesity, cancer, and Alzheimer’s disease.

The processing process which raises eyebrows

Canola oil processing raises some concern since the oil extraction process involves the use of hexane. Hexane is a well-known neurotoxin.

Canola oil manufacturers claim that all the hexane is removed during processing, but how far true is this? After all, saying things to make sales is not unheard of.  Although there is no evidence of health risks arising from ingesting traces of hexane, you have to think of what this may mean for the body’s toxic burden load. 

The oil also goes through a deodorization process – this process creates trans-fat. We all know that trans-fat is bad news, period. But again, manufacturers claim that they keep on modifying processes to limit the number of trans-isomers.

Most of the oil we buy comes with the ‘no trans-fat’ label, however, an independent study revealed that most of the commercial canola oil contains 0.56-4.2% trans-fat. The labels are written as such because manufacturers consider the amount of trans-fat in the oil to be safe according to food safety standards.

The big question is this, “aren’t consumers entitled to knowing exactly what they are consuming?” The lack of full disclosure is rather unsettling and it raises the question of what else is kept under wraps about the production process.

More not-so-great things about the oil include synthetic antioxidants and genetic modification.

• Canola oil manufacturers add synthetic antioxidants to make the oil last longer. These antioxidants are potentially carcinogenic and toxic if consumed over a prolonged period.
• The genetic modification undergone by the canola plant made the plant resistant to glyphosate (the main ingredient in the herbicide, Roundup). This means that farmers can spray the herbicide on their crop to control weeds. While this is good for business, continual exposure to glyphosate has links to fertility problems, hormone disruption, cancer, heart disease, and neurological problems.

The ugly…

Canola oil received a lot of attention when it was the subject of a study which showed a possible link to an increased risk of Alzheimer’s.  But everything is not as it seems – people went on to conclude how terrible canola oil is, based on an incomplete study.

The 2017 study claimed that mice, which were on a canola oil diet, displayed inhibited learning ability and signs of working memory suppression. The conclusion was interesting and there was a canola oil uproar for a minute, but there were lots of gaps in the methodology.

For starters, no group of mice was subjected to another oil diet, e.g. olive oil, for comparison. Additionally, the results were inconclusive as the mice only showed a slight difference in one out of three behavioural tests and one protein analysis. It’s a wonder how these results led to the ‘significant deficits of working memory’ conclusion.

Furthermore, the researchers made the mice’s obesity due to the canola oil diet a part of the findings. But one would think that mice feeding on fat would naturally show signs of obesity compared to those on a normal diet. So how did the obesity qualify to be a big finding?

At least the researchers themselves did say the results required more study. This means that ‘the ugly’ is not so ugly and the supposed link between canola oil and Alzheimer’s is inconclusive.

This is all great news, but ‘the bad’ still begs the question of whether canola oil is worth all the fuss.

And the conclusion

I’m no medical expert, but I do like using relevant and verifiable facts to draw conclusions. Based on past studies, researchers believe that canola oil lowers cholesterol. Nonetheless, there are concerns over the oil’s production and overall health benefits.

Canola oil has its merits and shortfalls, but so do other oils. For example, sunflower oil receives commendation for its health benefits, but it’s very high in omega-6. The oil may also not be the best cooking oil choice (it’s been shown to release toxic compounds when heated to high temperatures).   

Do the benefits of canola outweigh the bad? Are we better off vying for other cholesterol-lowering foods? Should we stop using canola oil altogether?

Perhaps the best solution is to take everything with a dollop of caution. It’s a good idea to work towards keeping everything healthy and consuming moderate amounts of oil, no matter what the oil is.

While canola oil is probably not as bad as other oils (no study has established any direct link to any disease), its health benefits are somewhat overrated. Those levels of omega-6 are quite high and most of the canola oil we consume is highly processed. We all know not to trust processed foods.

There are options

“You gotta have good olive oil. You should have a cooking olive oil and you should have a finishing olive oil, like an extra-virgin olive oil.“

Emeril Lagasse

The good thing is that there are other options. Olive oil, especially extra virgin, is almost always the best, and perhaps the healthiest choice.

Do keep in mind that when considering olive oil, there are two major issues; the oil is quite expensive and it has a low smoke point. The cost means olive oil may not be economical and the low smoke point makes the oil ideal for drizzling, sautéing, and baking, but not necessarily for deep-frying.

Tip: Some cheaper, healthy alternatives to olive oil that have higher smoke points include coconut, grapeseed, and avocado oil.

How you go about the cooking oil issue will depend on what works for you. For example, you can keep some olive at hand and avoid cooking with canola oil whenever you can. If you have to use canola oil, make sure to do it sparingly.

If you have a bit more to spend, go for cold-pressed canola oil, which is better because it skips the heavy processing bit.  Incorporate natural sources of healthy fats into your diet including fatty fish, seeds, and nuts, and use healthier forms of cooking like steaming, boiling, and grilling.

Whatever you do, keep it healthy and stay informed. That is what matters most in the end.

And if you’d like to explore the good and the benefits of other cooking oils, be sure to check out our blog on the good, the bad, and the ugly behind coconut oil.