Cold pressed canola oil

Question

Is there any scientific evidence that cold pressed canola oil in omega pills has deleterious effects on the consumer?

Example:

I have read this article:

Originally, rapeseed oil may not have had so many negative health effects. But for two main reasons, most canola oil today is harmful to your body:

1. Over 90 percent of canola oil is genetically modified

2. Canola oil is a partially hydrogenated oil

but I am dubious regarding its veracity.

Answer 1

There doesn't seem to be any evidence of harmful effects of canola oil.

The Mayo Clinic site states :

Health concerns about canola oil are unfounded. Canola oil, which is extracted from the seeds of the canola plant, is generally recognized as safe by the Food and Drug Administration.

Misinformation about canola oil may stem from the fact that the canola plant was developed through crossbreeding with the rapeseed plant. Rapeseed oil contains very high levels of erucic acid, a compound that in large amounts can be toxic to humans. Canola oil, however, contains very low levels of erucic acid.

There seems to be, on the contrary, evidence for health benefits.

However, I haven't been able to find any article on canola oil in omega supplementation specifically (especially vs. other plant oils or vs. fish oils). There is a lot of literature about consumption of these oils in general (an example about cardiovascular risk) but relatively few about fatty acid supplementation by pills in particular.

Edit to take count of the article you cited:

• According to the Mayo Clinic article cited previously, it's the reverse, rapeseed oil is dangerous while canola oil isn't.
• Canola oil can be hydrogenated, like all oils, but it's not always the case. Here, the pill bottle indicated 0g of trans fat, which indicates that the oil used in the pills isn't hydrogenated. But the law in the US allow companies to write 0g as long as it's under 0,5g so it might not be really trans fat-free. The term cold-pressed normally means the oil hasn't been heated, and thus isn't hydrogenated. Finally, I can't find a clear mention of whether indicating if an oil is hydrogenated is mandatory in the US or not, but the FDA (which banned trans fats in June) and the Mayo Clinic do recommend checking it to avoid trans fats, which seem to mean it's mandatory. Based on all this, I would think the canola oil in these pills isn't hydrogenated.
• There is no GMO labeling in the US. In 2006, 87% of the canola oil produced in the US was indeed genetically modified to be resistant to herbicides. In 2009, 90% of the canola oil produced in Canada was as well. There is no way of knowing if the canola oil in the omega pills is a GMO, but given these number it is likely.

Sources :

• Mayo Clinic on trans fats
• FDA