Canola Oil Linked to Dementia and Weight Gain, Study Reveals



Canola oil is often touted as heart-healthy, but narrow studies often overlook the damage it might do to our cardiovascular and cognitive health.

Canola oil is a common, inexpensive vegetable oil found in many store-bought products and restaurant meals. It has long been considered a healthy type of fat, but research now links this oil with Alzheimer’s and inflammation, as well as heart problems.

Read on for a breakdown of the many health concerns associated with highly-processed canola oil, and for healthier alternatives for cooking your meals.

What is Canola Oil?

Made from an edible version of the rapeseed plant, canola oil combines the words “Canada” and “ola” for Canadian oil, as it was originally produced by Canadian scientists. (1)

Today, more than 90 percent of the canola oil produced in the U.S. comes from GMO plants. (2) GMOs, short for genetically modified organisms, have been around since the 1980s. While many claim that they’re safe, there ] isn’t a large enough body of research proving that they are. For most, there are still too many unknowns surrounding GMOs and the heavy use of pesticides associated with them. (3)

Highly processed and refined, canola oil is cooked at 220ºF and then treated with a chemical solvent, known as hexane, to extract the oil. It is heated again to even higher temperatures to remove the hexane.

When canola oil is made into margarine, it’s treated to an additional process known as hydrogenation, which makes the fat solid at room temperature. However, this produces unnatural trans fats, which are associated with heart disease, sudden death from heart-related problems, and diabetes. (4)

Some countries even banned the use of any products containing trans fats, and the World Health Organization urged eliminating them entirely by 2023. (5, 6)

Canola Oil Nutritional Value

Canola oil contains a small amount of vitamin E and vitamin K, but apart from that, is void of nutrients. (7)

The majority of the fat content in canola oil is omega-6 fatty acids, which are found in abundance in the American diet. When omega-6 fats significantly outnumber omega-3s, health risks start to stack up, including heart disease, cancer, autoimmune disorders, and inflammation. (8)

The optimal ratio between omega-6 and omega-3 is 1:1, but the standard American diet creates a ratio closer to 15:1. (9)

Alzheimer’s, Dementia, and Memory Problems

In animal studies, canola oil was linked to memory problems and Alzheimer’s. (10, 11) Imbalances in the ratio of omega-6 to omega-3 fats can alter the brain in a negative way, and is associated with the development of Alzheimer’s, dementia, and cognitive decline. (12)

When comparing intake of canola and other refined oils to that of extra virgin olive oil, research found that those eating olive oil experienced improved brain and cognitive function, whereas the refined oils were not found to be protective. (13)


The body doesn’t only rely on a healthy fat ratio for brain health, but for overall body health and weight balance, too. When omega-6 fatty acids significantly outweigh omega-3s, the result can lead to changes in systemic inflammation and the type of fat that’s stored, resulting in higher body weight and increasing prevalence of overweight and obesity. (14)

Heart Disease

Omega-3 fats help to promote healthy vascular function as well as healthy blood pressure levels. (15) Omega-3 fats also have the power to influence gene expression, meaning that genetic mutations can be turned on or off in response to omega-3 fatty acid levels. (16) This can directly influence the chances of developing coronary heart disease, hypertension, and other chronic disorders.

Canola oil can disrupt omega-3 fatty acid balances, and fails to contribute heart-healthy fats to the diet. (17) Excessive omega-6 fatty acid intake contributes to cardiovascular disease and inflammation, whereas omega-3 fats suppress the risk. (18)

Metabolic syndrome is associated with an increased risk of heart disease, and one study showed that those who normally used canola oil for cooking were more likely to have metabolic syndrome than those who did not use it frequently. (19)

Studies reporting health benefits of canola oil often overlook the big picture, focusing on narrow improvements. For example, an analysis of more than 450 men who used vegetable oils showed that they did have lower levels of LDL cholesterol (the kind that is considered “bad”), but overall, they had higher rates of death and heart disease. (20)


While vegetable oils like corn, canola, safflower, sunflower, soy, and cottonseed, are often touted as healthy, research in animals ties them, and especially canola oil, to increased levels of inflammation and blood pressure as well as a decreased life span. (21)

Another study found that heating canola oil worsens inflammatory markers. (22) When inflammation turns into a chronic problem, it is the driving factor behind numerous diseases and health problems like heart disease, depression, autoimmune disorders, diabetes, and even obesity. (23, 24, 25, 26)

3 Best Replacements for Canola Oil

There are many healthier options than canola oil, and these alternatives have proven health benefits without the risk for inflammation.

Olive Oil


Extra virgin olive oil is chock-full of health benefits, including better heart health, protecting the brain against Alzheimer’s, and decreasing the risk of stroke. (27, 28, 29)

Olive oil is rich in unsaturated fats that are linked with decreased inflammation and the reduced risk of neurodegenerative disease. (30) The Mediterranean Diet can credit most of its health benefits to the regular intake of extra virgin olive oil. (31)

Avocado Oil


Avocado oil is more heat-resistant than olive oil, making it a good choice for cooking. It protects the mitochondria in cells from free radical damage. (32)

Animal studies show that avocado oil improves antioxidants in the body, protecting organs from damage associated with chronic disorders. (33) In further animal studies, it has also been shown to decrease risk factors for cardiovascular disease and protect the brain against oxidative and inflammatory damage. (34, 35)

Coconut Oil


Coconut oil is a heart healthy option that protects against cardiovascular disease and also supports brain health, human and animal studies suggest. (36, 37, 38) It can even improve cognitive performance in those with Alzheimer’s. (39)

In human and animal studies, virgin coconut oil protects cells and can defend against oxidative damage and cell death, leading to improved health and a longer life expectancy, especially in chronic disorders. (40, 41)

Bottom Line

Opt for whole, unprocessed oils like olive, avocado, and coconut. These healthier, anti-inflammatory oils are backed by more definitive research on health benefits and are free from a high-heat, chemical extraction process.

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