Even though olive oil is called healthy, it still has enough bad fat in it to break down when heated — more than butter or ghee.

Olive oil, due to its 11% polyunsaturated fatty acid content, exhibits greater oxidative degradation under heat compared to animal fats with <5% polyunsaturated fat content.

When you heat olive oil really hot, the healthy unsaturated fats break down much faster than the saturated ones—oils with more unsaturated fats lose them the most, making the oil less healthy.

When you cook olive oil at very high heat, the good unsaturated fats break down faster than the saturated ones — especially in oils that started with more unsaturated fats, making them less healthy for cooking.

Avocado oil contains 13–15% polyunsaturated fatty acids, rendering it susceptible to thermal oxidation despite a high monounsaturated fat content.

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.