No, seed oils are not toxic or cancer-causing

What’s the claim?

Seed oils have become a hot topic in health and nutrition over the past few years. On TikTok, warnings about seed oils are gaining traction. Influencers claim they're toxic, causing conditions like acne, weight gain, and even cancer. 

Some claim that seed oils are carcinogenic, advising people to opt for "healthy saturated fats like butter" rather than "toxic" seed oils “that are cancer-inducing.” An archived version of such a claim made by a user on TikTok can be accessed here. The post gained more than 1000 likes, and 123 reshares at the time of writing this story. 

Screenshot of the claim made online. (Source: TikTok/ Modified by Logically Facts)

What we found

Logically Facts found that seed oils are not inherently carcinogenic. The World Cancer Research Fund analyzed recent scientific findings on the relationship between fats, oils, and cancer risk. They concluded that moderate consumption of vegetable and seed oils does not elevate cancer risk. A regulated intake of these fats aids the body in absorbing certain vitamins.

What is seed oil?

Seed oils are oils extracted from the seeds of plants, such as soybeans, corn, sunflower, and canola. These oils are commonly used in cooking and food preparation due to their neutral flavor and high smoke point.

Furthermore, seed oils primarily fall under the category of unsaturated fats. They are rich in mono and polyunsaturated fats, considered healthier than saturated and trans fats. The report adds that saturated fats in foods like butter, cheese, and red meat can increase the risk of certain chronic diseases.

Concerns surrounding seed oils and cancer

Concerns are linked to the omega-6 fatty acids in seed oils and the potential imbalance between omega-6 and omega-3 fatty acids in one's diet.

According to research by the National Library of Medicine, excessive intake of omega-6 fatty acids, especially when not balanced with sufficient omega-3 fatty acids, may promote inflammation and contribute to an increased risk of certain chronic diseases, including cancer.

Nonetheless, other elements such as dietary habits, lifestyle, genetics, environmental factors, and excessive use of seed oils also play critical roles in health risks.

The British Heart Foundation notes that high consumption of saturated fats is associated with various health issues, including heart disease, high cholesterol levels, and obesity. Limiting saturated fats and focusing on healthier fats, like unsaturated fats, is advised to maintain heart health.

Guy Crosby, Ph.D., Adjunct Associate Professor of Nutrition, told Logically Facts, “I am not aware of any studies that show that seed oils such as canola and soybean oils are cancerous. Nor are there any significant health risks from consuming these oils in modest amounts. The real issue that should concern consumers is the consumption of too much fried food, which is linked to cardiovascular disease. The formation of excessive oxidation products, formed from seed oils in deep fat fryers where the frying oil is not changed on a regular basis (every few days), have been shown to cause cardiovascular problems when fried foods are consumed three or more times per week.”

According to a report published by Harvard University, seed oils, being rich in unsaturated fats, supply essential nutrients and can contribute to a healthy diet when consumed in moderation and as part of an overall balanced diet.

According to Open Oregon Educational Resources, the human body requires fats for various essential functions, including serving as a concentrated energy source, contributing to the structure of cell membranes, aiding in the absorption of fat-soluble vitamins, facilitating hormone production, and providing insulation and protection for organs. Consuming healthy fats is crucial for overall health and well-being.

The verdict

There is no credible evidence that moderate seed oil consumption increases cancer risk. Experts recommend moderation when consuming seed oils, emphasizing the importance of a balanced diet. Therefore, we mark this claim as false.