Before grocery store shelves were stocked with avocado, coconut and walnut oil, there was canola oil.
But now with the myriad of cooking oil choices, there's a movement on TikTok claiming that the vegetable-based oil is toxic. The hashtag #canolaoil has amassed over 47 million views. Some influencers have insisted that the oil can cause inflammation; others have compared it cooking with it to consuming motor oil.
Does canola oil deserve this negativity? TODAY.com spoke with two registered dietitians to get to the bottom of this TikTok health trend.
Meet the experts
- Frances Largeman-Roth registered dietitian nutritionist and author of "Eating In Color: Delicious, Healthy Recipes for You and Your Family"
- Bonnie Taub-Dix, registered dietitian nutritionist, creator of BetterThanDieting.comand author of "Read It Before You Eat It: Taking You From Label to Table"
What is canola oil?
Canola oil is meant to be a neutral oil, Frances Largeman-Roth, registered dietitian nutritionist and author of "Eating In Color: Delicious, Healthy Recipes for You and Your Family," says. In this way, it's unlike olive oil, which has a distinctive taste and cannot be used for all purposes.
“When (canola oil) was developed, people were looking for a cooking oil that could be used for baking, stir frying, deep frying,” Largeman-Roth tells TODAY.com.
Canola oil is derived from rapeseed. This bright yellow flowering plant species is part of the cabbage and mustard family, she says.
It's true that rapeseed is very high in erucic acid, which is toxic in large amounts, she says. That’s why a group of Canadian scientists in the 1970s began crossbreeding a different variation of rapeseed. They called it "canola," a play on Canadian oil.
With very low levels of erucic acid and glucosinolates (which aren't harmful but taste bitter), canola oil was developed to taste smoother and be healthier than other oils available at the time, Largeman-Roth explains.
It goes through a processing similar to other oils typically found in the American diet, such as corn, soybean and sunflower. They are all treated at high heat, and a solvent is used to extract the oil from the seed, she adds.
With canola oil specifically, the chemical hexane is used as a solvent. But the trace amount of hexane is not at any sort of dangerous levels, per Largeman-Roth.
A 2018 report published by Harvard T.H. Chan School of Public Health backs this up:“There appears to be very little reason for concern about the trace levels of hexane in canola oil,” Dr. Guy Crosby, adjunct professor of nutrition, wrote.
Canola oil is refined, bleached and deodorized because consumers expect cooking oil to have a lightened color with no flavor, Largeman-Roth says. She notes that the top four vegetable oils consumed in the United States — soybean, canola, palm and corn oil — all go through this same process.
“They are highly processed oil,” she says. “But again, that is to make them shelf stable and also to provide that neutral flavor.”
Canola oil is even the crux of the Nordic diet, which is characterized by plant-based, seasonal foods that are high in protein, complex carbohydrates and healthy fats, Largeman-Roth says. Research has shown the Nordic diet can reduce blood sugar and cholesterol.
“It’s not just Americans who eat canola oil,” she says. “It’s used around the world.”
Is canola oil bad for you?
It may not be time to cut canola oil out of your diet completely.
While there are healthier alternatives — such as olive and avocado oil — canola oil is not toxic, Bonnie Taub-Dix, registered dietitian nutritionist and author of “Read It Before You Eat It: Taking You From Label to Table," tells TODAY.com.
Canola oil does contain small amounts of trans fat (even if the nutrition label reads "0 grams") because "pretty much all vegetables oils do," she says. But canola oil is actually one of the American Heart Association's healthy cooking oils because it's low in saturated fats and high in monounsaturated and polyunsaturated fats.
Some canola oil critics have called out the presence of erucic acid and research that's found it's associated with heart lesions. In reality, though, canola oil's erucic acid levels are low after it is processed, Taub-Dix explains.
What's more, the only research that supports claims of erucic acid causing heart lesions has been in lab animals, Largeman-Roth says.
“They have not found these lesions in humans, and again those high levels (of erucic acid) are in rapeseed, not canola oil,” she stresses. “Technically they are the same plant, but canola oil is a variety of rapeseed."
“If you were a farmer and you were going to plant canola seeds to be turned into oil, you would get the canola seeds that are low in erucic acid. You would not want to be buying the rapeseed to plant," she adds.
Canola oil also contains a fatty acid called alpha-Linolenic acid, which is a plant form of omega-3 fatty acids, which support heart health, per Largeman-Roth. “We’re supposed to be getting more omega-3 fats in our diet, not less," she says.
Eating a lot of foods that have an imbalance in the ratio of omega-6 fatty acids (which are good for the heart if eaten in moderation instead of saturated fats, per Mayo Clinic) to omega-3s can lead to inflammation in the body, Taub-Dix says.
Inflammation is associated with heart disease, gastrointestinal disorders and more, according tot he National Institutes of Health. But, Taub-Dix stresses, canola oil has an omega-6 to omega-3 ratio of two to one, so it doesn’t have that high of an inflammation risk.
“The average American diet is 15 to 1 (omega-6 to omega-3),” she says. “I think it’s putting things in perspective and not blowing things out of proportion.”
What to know about consuming canola oil safely
The key to consuming canola oil is moderation, the dietitians say.
Instead of solely grabbing canola oil from the kitchen cabinet, Largeman-Roth recommends adding a few other oils into the rotation.
“Variety helps us not only get the most nutrients, but also, if there is something in the food supply that might have a trace element of something that we shouldn’t be having, then your exposure is lower if you have a variety of things in your diet,” she explains.
Taub-Dix recommends being mindful of portion sizes, especially for oil. Many people do not realize that one cup of any type of oil has about 2,000 calories, even if it has nutritious properties, she says.
Bottom line: No, canola oil isn't toxic, but whether or not it's bad for you as an individual depends on a lot of factors, Taub-Dix says, for example your current health and what else you're eating.
"You can’t just take it out of context to say this is toxic without knowing anything else about what else is in the diet," she adds.