Olive oil, which has lots of oleic acid, makes more of certain toxic aldehydes like 4-HNE and 2-decenal when heated than oils like soybean or palm.

When you heat olive oil, it makes more of two harmful chemicals — HNE and ONE — than the other oils tested, likely because it’s high in oleic acid.

Extra virgin olive oil produces higher levels of polar compounds and oxidative byproducts than saturated animal fats and coconut oil when subjected to prolonged heating.

Cooking olive oil at a very high temperature for an hour almost completely destroys the fresh, grassy smell that makes good olive oil taste good.

When subjected to prolonged heating, extra virgin olive oil generates significantly higher levels of polar compounds and lipid oxidation byproducts than coconut oil and ghee.

Prolonged heating of extra virgin olive oil generates significantly higher levels of polar compounds and oxidation byproducts than coconut oil and ghee.