Most oils used in cooking are seed oils--in other words they are extracted from seeds. According to some wellness influencers and pundits, many seed oils (canola, corn, sunflower, cottonseed, soybean, safflower, grapeseed and rice bran oils) are deadly for our health, causing increased rates of obesity, diabetes, and other chronic diseases. This notion is pure nonsense.
Seed Oils and Inflammation: What the Science Actually Says
The central claim is that seed oils cause inflammation because they contain omega-6 fatty acids. This is an oversimplification — and a persistent one. Omega-6 fats are essential fats. Our bodies require them to function, and we cannot produce them on our own. The concern is rooted in the ratio of omega-6 to omega-3 fatty acids in the diet. In theory, an extreme overload of omega-6 relative to omega-3 could promote inflammatory pathways. In practice, this doesn't happen in real human diets — seed oils or not. Decades of research show that normal consumption of omega-6 fats does not increase inflammation markers or disease risk. In fact, replacing saturated animal fats with seed oils is associated with several beneficial cardiovascular effects. Much of the fear stems from a fundamental misunderstanding of how fats and inflammation interact. The fear sounds scientific enough to spread online, but it doesn't survive scrutiny.
Are Seed Oils "Processed"? Yes — So Is Most Everything Else
A second line of attack is that seed oils are "industrial" or "unnatural." This is rhetoric, not science. Many perfectly healthy everyday foods are processed in some way. Processing alone does not make a food harmful — what matters is its chemical composition and its actual health effects. Oils that the "seed oils are bad" crowd considers acceptable, such as olive oil and avocado oil, are also processed. Cold-pressing is still a mechanical extraction process. This is the same reasoning pattern behind the false claim that high-fructose corn syrup is uniquely harmful — "industrial processing = toxic" — and the evidence doesn't support it there either. The myth that gluten is broadly harmful follows the same fear-of-modern-food illogic.
Seed Oils Health Research: What Does the Evidence Show?
Refined seed oils are stable, safe to consume, and tightly regulated. "Toxic" claims are not supported by credible evidence. Ultra-processed food as a category does raise genuine nutritional concerns — see is all ultra-processed food bad for you? — but that's about dietary patterns and nutrient density, not a condemnation of seed oils as a specific ingredient. The bottom line: if you're using canola or sunflower oil to cook with, you're fine.
