Seed Oils
The new trans fats? Seed oils (vegetable oils) like canola, soybean, corn, and sunflower are highly processed, omega-6 heavy, and prone to oxidation. They're in nearly everything processed and are the primary cooking fat in restaurants. Many health advocates suggest avoiding them.
Seed Oils to Avoid
Canola/Rapeseed
Most common. Heavy processing. Hexane extraction.
Soybean Oil
#1 consumed oil in US. In everything processed.
Corn Oil
Very high omega-6. GMO corn source.
Sunflower Oil
High oleic slightly better. Regular very high omega-6.
Safflower Oil
Highest omega-6 of all. Avoid.
Cottonseed Oil
Heavy pesticide crop. Not food grade originally.
Grapeseed Oil
Marketed as healthy. Still very high omega-6.
Rice Bran Oil
Common in Asian cooking. High omega-6.
Why They May Be Harmful
Omega-6 Excess
Linoleic acid competes with omega-3. Promotes inflammatory pathways when excessive.
Oxidation
Polyunsaturated fats oxidize easily. Heat, light, air create harmful compounds.
Processing
Hexane extraction, deodorizing, bleaching. Nothing natural about the process.
Cell Membrane
Fats incorporate into cell membranes. Affects membrane fluidity and function.
Mitochondrial Damage
Oxidized fats damage mitochondria. Impair energy production.
Chronic Disease
Correlates with rise of heart disease, obesity, diabetes. Causation debated.
Better Fat Choices
Extra Virgin Olive Oil
Low heat cooking, dressings. Polyphenols. Mediterranean staple.
Butter/Ghee
Grass-fed ideal. Stable for cooking. Butyrate for gut.
Coconut Oil
Saturated, very stable. MCTs for energy. High heat cooking.
Avocado Oil
High smoke point. Mostly monounsaturated. Quality varies.
Tallow/Lard
Traditional fats. Stable, nutritious. Pasture-raised source.
Duck Fat
Delicious for cooking. Good fatty acid profile. Traditional.