Olive oil from Al-Jouf stays fresher longer than olive oil from Pakistan when left out at room temperature, based on how quickly it breaks down.

The way olive oil is made and stored in different places might help it last longer, but we can't say for sure which part makes the difference.

When you heat olive oil at high temperatures for a long time, it makes more of two harmful chemicals—HNE and ONE—than the other oils, because olive oil is mostly made of oleic acid.

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.

Scientists can tell if olive oil is going bad by shining light on it and watching how the color changes — darker spots mean the good stuff is breaking down, and brighter spots mean bad stuff is forming.

Extra virgin olive oil lasts longer when frying than regular olive oil because it has more natural antioxidants built in.