Are Vegetable and Seed Oils “Harmful”?!

From TikTok trends to bestselling publications, vegetable oils—widely referred to as “seed oils”—have sparked considerable discussion. The controversy surrounding their benefits dates back to their introduction in the market. With the rise of the carnivore diet, aversion to vegetable oils has intensified on social platforms. Many posts label these oils as “toxic sludge” or “motor oil” and assert they significantly contribute to chronic illnesses.

Critics contend that while animal fats have historically been consumed by humans, vegetable fats were developed more recently for profit. They argue that vegetable oils, presented as healthier alternatives to butter, in fact heighten the risk of obesity, mental health disorders, and various health issues.

On the other hand, some specialists claim that vegetable oils are safe, potentially beneficial for health, and preferable to butter. The reality is nuanced, and this article intends to separate scientific facts from pseudoscience to assist in making educated choices regarding dietary oils.

What Exactly are Vegetable Oils?

Vegetable oils, known as seed oils, are derived from the seeds of plants. Common varieties include corn, canola, safflower, sesame, sunflower, soybean, and grapeseed oil. Importantly, oils like olive, avocado, palm, and coconut are not classified as vegetable oils since they are obtained from fruits.

How are Vegetable Oils Manufactured?

In contrast to naturally oily items like olives, many seeds contain low amounts of fat, necessitating significant processing to obtain the oil. This involves crushing, refining with solvents like hexane, and deodorizing through heating at 400 F for several hours. These procedures may result in the loss of valuable nutrients and produce trans fatty acids (partially hydrogenated fats). While labeling these oils as “harmful” is an overstatement, nutrition scientists recommend limiting trans fats, and the FDA prohibited their addition to foods in 2018.

What Cooking Oils Are Recommended?

According to Precision Nutrition (PN), certain vegetable oils like expeller-pressed canola oil and high-oleic sunflower and safflower oils are categorized as “Eat Some”—neither detrimental nor particularly beneficial in moderate consumption. Other vegetable oils and saturated fats fall under the “Eat Less” category.

Extra-Virgin Olive Oil vs. Expeller-Pressed Canola Oil

Both oils rank among the least processed. Extra virgin olive oil (EVOO) is abundant in monounsaturated fatty acids (MUFAs) and polyphenols, which aid in reducing inflammation and protecting cells. Research connects EVOO consumption with decreased risks of heart disease, hypertension, type 2 diabetes, dementia, and cancer. In contrast, canola oil, with its monounsaturated fats and phytosterols, lacks the same level of research support. EVOO remains the superior pick, although expeller-pressed canola serves as an economical, moderately healthy choice.

Expeller-Pressed Canola Oil vs. Refined Canola Oil

Expeller-pressed canola oil preserves beneficial components by avoiding heat or solvents during extraction. Refined canola oil, however, loses some advantageous nutrients and accumulates unhealthy trans fats. While expeller-pressed canola oil is a better option, the difference is minimal since canola oil typically begins with a less controversial fatty acid profile compared to other vegetable oils.

Refined Vegetable Oil vs. Butter

This discussion is highly contentious. Opponents of refined vegetable oils point to the instability of polyunsaturated fats and their extraction of protective compounds during processing, which makes them susceptible to oxidation and may elevate inflammation. Ultra-processed foods, rich in refined oils, present more severe health risks than meals cooked at home. Conversely, butter, while containing saturated fats, is less processed but should still be consumed in moderation.

Some Final Thoughts

If the budget allows, EVOO is an excellent choice given its proven health benefits. Cold-pressed avocado and walnut oils are also great alternatives, offering high levels of antioxidants and MUFAs. For those on a tighter budget, expeller-pressed canola oil is a viable option. High-oleic sunflower and safflower oils also provide cardiovascular advantages when they replace saturated fats. Regardless of your selection, prioritizing whole, minimally-processed foods and healthy fats like MUFAs is key, while limiting ultra-processed items and deep-fried dishes for improved health results.

References can be provided upon request, detailing the sources for the claims made throughout this article. For tailored nutritional guidance, check out Precision Nutrition’s website.