Is It Safe To Cook With Canola Or Vegetable Oil? Experts Explain

There are a lot of confusing nutrition topics out there, but cooking oils are near the top of the list. Over the years, there's been a big push toward canola and vegetable oils since they're high in unsaturated fats and low in saturated ones, but an isolated nutrition profile doesn't always tell the whole story—and that's especially true in this case.

Let's start with canola oil. Canola oil (or rapeseed oil) is a neutral-tasting oil that's made by crushing the seeds of the canola plant. That sounds simple enough, but there's a lot that goes on behind the scenes to get there.

The canola plant actually started out as the rapeseed plant, but as is, rapeseed contains two toxic compounds—erucic acid and glucosinolates—and can't be safely consumed. According to registered dietitian and certified diabetes educator Shahzadi Devje, R.D., CDE, MSc, Canadian scientists figured out how to remove these compounds through targeted plant breeding and came up with the canola (Can for Canada and ola for oil) plant.

To make canola oil, oil is extracted from the canola plant through a long manufacturing process that involves chemicals like hexane, Devje says.

Vegetable oil isn't a specific type of oil; it's more a general term that's used for any oil that comes from plants, including seeds, grains, nuts, and/or fruits. That being said, when referring to "vegetable oil," people most often mean soybean oil. 

However, it's worth noting that most commercial vegetable oils are actually a mishmash of different types of inexpensive oils, including soybean and corn. Since the term "vegetable oil" is so vague, manufacturers can add a blend of oils without technically being misleading.

The short answer? Neither. Aside from being highly processed and (most likely) genetically modified, the polyunsaturated fats in canola and vegetable oil are largely omega-6 fatty acids. This isn't necessarily a problem on its own, but it becomes an issue when you look at the bigger picture. 

Before industrialization and oil refining came into play, our diets were full of omega-3 fatty acids that came from wild game, wild-caught fish, plants, and natural fats. Once the focus shifted to liquid vegetable oils and farm-raised animals instead, our omega-6 consumption skyrocketed, while intake of omega-3 fatty acids started to fall short, according to functional medicine doctor Mark Hyman, M.D.  

To put it into perspective, studies1 show that the ideal ratio of omega-6s to omega-3s is 2:1. Right now, the average American consumes 10 to 20 times more omega-6s than omega-3s2 (a ratio of 10:1 to 20:1).  

Sure, consuming a large amount of unsaturated fats sounds good, but the problem is that omega-6 fatty acids can have pro-inflammatory effects. And unless you're balancing it out with the anti-inflammatory properties of omega-3s, you're not doing yourself any favors. Omega-6 fatty acids also decrease the conversion of alpha-linolenic acid (a plant-based omega-3 fat) into the active forms of omega-3 (EPA and DHA) by as much as 40%, according to Hyman.

Aside from that, canola oil is one of the least healthy oils for other reasons. It's highly processed and usually stripped of nutrients, says nutritionist and mindbodygreen Functional Nutrition Training instructor Serena Poon, C.N., CHC, CHN.