Olive oil and frying: myth or health savior?

Fried food is considered dangerous. When food is fried in animal fat, there’s no doubt about it. It’s harmful. And very much so! But what about the use of plant-based fats?

In general, the use of vegetable oils is considered healthier. Fried foods are mainly harmful because of aldehydes, which form at high temperatures. These are simple organic structures that bind with oxygen and carbon and contribute to the development of diseases like diabetes, heart, and vascular diseases. In general, we should avoid aldehydes.

Scientists from Cardiff Metropolitan University have made a thorough comparison of foods fried in sunflower, flaxseed, and olive oil.

Olive oil is considered extremely healthy and is rich in antioxidants—but this applies when it’s in its cold state. But what happens if you heat it to 190 degrees Celsius, which is the usual frying temperature?

The researchers found that sunflower and flaxseed oils produce roughly the same amount of harmful aldehydes, while quality olive oil produces five times fewer. However, this is because the processes in olive oil occur more slowly, so fewer aldehydes are formed.

Put differently: if you don’t heat olive oil for more than 5 minutes, there are so few aldehydes that there’s almost no risk. If, however, you heat the oil for more than 10 minutes, so many hazardous substances form that it’s better not to eat anything fried, even if you use the highest quality olive oil.

In any case, olive oil is very healthy, but despite everything, it’s best to avoid fried foods.


Information on this website is for educational purposes only and is not medical advice.