As the debate over seed oils heats up, many people are still scratching their heads about canola oil.
Although more and more people are realizing that oils such as soybean oil and corn oil aren’t the healthiest options, canola oil — despite its similarities to these seed oils — often gets a pass because it’s “heart healthy.”
Still, there are many potential health concerns of canola oil that it’s important to be aware of.
What is Canola Oil?
Canola oil, also known as rapeseed oil, is a cooking oil made from the seeds of the rapeseed plant, a flowering plant in the Brassica family.
It’s an extremely popular cooking oil choice in the United States and around the world, thanks to its neutral taste profile, high smoke point (which makes it ideal for frying foods), and low cost.
However, it’s not an easy or straightforward process to extract oil from rapeseed and make it edible.
How is Canola Oil Made?
Canola oil must undergo intensive industrial processing to become a clear, tasteless oil that’s appropriate for cooking.
First, the oil must be extracted from the seed. This can be accomplished through physical pressing of the seed, although this isn’t very efficient. Usually, a chemical process involving hexane is used to help extract the oil (*).
However, the resulting crude oil is cloudy, dark, and strong-smelling. There are still many more steps to make it ready to be bottled and sold. These include (*):
- Degumming: removes phospholipids and gums
- Neutralizing: removes other compounds such as chlorophyll, metals, and free fatty acids
- Washing and drying: removes soaps and water
- Bleaching: removes pigment-containing compounds to give the oil a uniform, light color
- Dewaxing/winterization: removes waxes, allowing the oil to remain fluid in cold temperatures
- Deodorizing: eliminates odor-causing volatile compounds
Canola Oil Nutrition
One tablespoon of canola oil contains (*):
- Calories: 124
- Fat: 14 grams
- Protein: 0 grams
- Carbs: 0 grams
This is in line with most other fats and oils, all of which provide roughly 120 calories per tablespoon — all from fat.
Is Canola Oil Bad for You?
Canola oil is probably not the best cooking oil for optimal health.
There are a number of concerns with canola oil and other highly-processed seed oils.
We will dive deeper into these concerns below, but they include the fact that canola oil is highly processed, rich in pro-inflammatory omega-6 fats, and unstable — all of which could lead to worse health outcomes.
Is Canola Oil Heart Healthy?
Canola oil has a “heart healthy” reputation because it’s low in saturated fat and high in monounsaturated fat.
However, it’s really important to understand that the idea of saturated fat causing heart disease is an outdated concept.
Research shows that saturated fat, which mostly occurs in natural sources like beef, pork, and coconut, has no link to heart disease (*).
Still, this belief persists among the general public, and even among some healthcare professionals.
However, it’s very important to understand that “low in saturated fat” does not equal “heart healthy.”
Additionally, there are other monounsaturated fat-rich oils, like olive oil and avocado oil, that don’t have the same health risks as canola oil and that also offer heart health benefits (*, *).
Canola Oil Health Risks
Here are the major concerns with canola oil and its potential health risks.
Genetically Modified
The vast majority of canola oil is made with genetically modified rapeseed. While there is a lot of ongoing debate about the potential risks of genetic modification itself, one of the major problems with GMO crops is that they’re sprayed with large amounts of pesticides.
Some of these pesticides, like glyphosate, are known toxins and potential cancer-causing agents. These pesticide residues also persist even in refined oils (*, *).
Highly Processed
Additionally, canola oil and other seed oils are highly processed. Highly processed foods in general have been linked to weight gain, type 2 diabetes, heart disease, depression, high blood pressure, and several other health conditions (*).
Because there are other, less processed alternatives available, canola oil may not be the best choice due to its degree of processing.
Unstable and Oxidizes Quickly
Canola oil and other seed oils are rich in polyunsaturated fats. Although some research says that polyunsaturated fats can be helpful for heart health, they may not be ideal. Unlike saturated fats, which are fully saturated with hydrogen and therefore very stable, and monounsaturated fats, which are mostly saturated with the exception of one carbon-carbon double bond, polyunsaturated fats contain multiple double bonds — representing multiple points of instability (*, *).
This makes these oils especially fragile, and can lead to the build-up free radicals and other harmful compounds when the oil is heated. When the oil is heated and cooled repeatedly, such as in restaurants that serve fried food, this problem is compounded. Large quantities of these compounds can lead to oxidative stress, which causes damage to the body at a cellular level and could contribute to chronic health problems such as type 2 diabetes and heart disease (*, *, *).
High in Omega-6 Fats
Finally, canola oil and other seed oils are rich in omega-6 fats. We need a specific ratio of omega-3 and omega-6 fats for optimal health, but right now — mostly because of these oils — we are consuming larger quantities of omega-6 than ever before (*).
This imbalance promotes inflammation, which is a driver of several chronic health problems including type 2 diabetes, heart disease, and cognitive decline (*, *).
Canola Oil Alternatives
Fortunately, there are a number of healthier fats and oils for cooking. Some of the best include:
- Olive oil: Extra virgin olive oil doesn’t require the same amount of extensive processing that seed oils do. Additionally, olive oil is rich in monounsaturated fats that have been linked to better heart and overall health (*, *).
- Avocado oil: Likewise, avocado oil requires minimal processing compared to other oils. It’s also a rich source of monounsaturated fats (*).
- Coconut oil: Coconut oil is unique in that it is a plant-based source of saturated fat, making it a very stable oil to use for cooking.
- Butter and ghee: Butter and ghee (clarified butter) are excellent choices. They are rich in saturated fat from dairy.
- Animal fats: Finally, animal fats — such as tallow, lard, bacon grease, and duck fat — are some of the best choices for cooking. They are very minimally processed and extremely stable thanks to their high saturated fat content. However, they tend to be the most expensive.
Remember, you can make the switch slowly — you don’t have to remove all canola oil and other seed oils from your diet at one time.
As you run out, you can gradually replace less-healthy cooking oils (or foods made with these less-healthy cooking oils) with healthier alternatives.
The Bottom Line
Canola oil is a highly-refined seed oil, much like corn oil and soybean oil. However, although many people are starting to understand the downsides of many of these seed oils, canola oil is still considered healthy by many.
This is because it’s low in saturated fat and richer in monounsaturated fat than other seed oils. However, it still has a number of potential health risks. Additionally, saturated fat intake is not related to heart health.
Overall, it’s best for optimal health to eliminate canola oil and other seed oils from your diet as much as possible. Still, you don’t have to tackle this momentous task all at once — slow and steady improvements are still improvements.