Fats and oils: why is reusing cooking oil for frying dangerous?

Reusing the same vegetable oil for frying is a common culinary mistake that poses a serious threat to health. When heated intensely, thermal oxidation and degradation processes are triggered in the oil.

When oil is reheated, toxic compounds form in it, including free radicals, aldehydes, and polycyclic aromatic hydrocarbons. These substances have carcinogenic properties and can accumulate in the body, increasing the risk of developing oncological diseases and cardiovascular pathologies.

Furthermore, reheating completely destroys all beneficial microelements and vitamins that may have originally been present in the oil. The structure of fatty acids also changes, turning them into compounds that are difficult to digest, causing heartburn, a heavy stomach, and liver dysfunction.

For safe cooking with oil, basic nutritional hygiene rules should be followed.