At the start of frying, mixing sesame oil makes olive oil more antioxidant-rich, but after 12 hours, all oils lose their antioxidant power — extra virgin olive oil just starts higher and lasts a bit longer.

After frying for 12 hours, regular olive oil loses almost all its healthy compounds, but extra virgin olive oil still keeps about a third of them — adding sesame oil doesn’t help preserve them.

Adding a little sesame oil to regular olive oil helps it last longer when frying food because it slows down the oil going bad.

Adding sesame oil to extra virgin olive oil doesn’t make it last longer when frying because it’s already packed with natural antioxidants.